0001410939-23-000025 | 10-K | XBRL Viewer

Property and Equipment

12 Months Ended

Dec. 31, 2022

Property, Plant and Equipment [Abstract]

Property and equipment as of December 31, 2022 and 2021 were as follows:


	Useful Life (Years)	December 31, 2022		December 31, 2021
Research, manufacturing and clinical equipment	5 - 10	$	548	$	283
Computer, software and other office equipment	5	1,201		933
Furniture and fixtures	7	203		—
Automobile	5	125		125
		2,077		1,341
Accumulated depreciation		(1,131)		(993)
Property and equipment, net		$	946	$	348

For the years ended December 31, 2022, 2021 and 2020, depreciation expense was $138 thousand, $39 thousand and $143 thousand, respectively.

Net Income (Loss) Per Common Share (Tables)

12 Months Ended

Dec. 31, 2022

Earnings Per Share [Abstract]

Schedule of Computation of Basic and Diluted Net Income (Loss) per Common Share

The following table sets forth the computation of basic and diluted net income (loss) per common share for the periods indicated:


	Years ended December 31,
	2022		2021		2020
Basic and diluted net income (loss) per common share calculation:
Net loss	$	(185,211)	$	(114,522)	$	(84,547)


Weighted average common shares outstanding - dilutive	121,037		101,866		74,185
Net loss per common share - basic and diluted	$	(1.53)	$	(1.12)	$	(1.14)

Schedule of Potentially Dilutive Securities Excluded from the Computations of Diluted Weighted Average Common Shares Outstanding

The following potentially dilutive securities have been excluded from the computations of diluted weighted average common shares outstanding for the periods presented, as the effect of including such shares would be anti-dilutive:


	Years ended December 31,
	2022	2021	2020
Stock options outstanding	12,402,629	10,861,483	8,927,698
Restricted stock units	3,025,941	2,246,269	1,958,383
Total	15,428,570	13,107,752	10,886,081

Licensing and Commercialization Agreements	12 Months Ended
Licensing and Commercialization Agreements	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Licensing and Commercialization Agreements	Licensing and Commercialization Agreements ACP License Agreement with Archemix Corp. In September 2011, the Company entered into an amended and restated exclusive license agreement with Archemix Corp. ("Archemix") relating to anti-C5 aptamers (as amended, the "C5 License Agreement"). The C5 License Agreement superseded a July 2007 agreement between the Company and Archemix. Under the C5 License Agreement, the Company holds exclusive worldwide licenses, subject to certain pre–existing rights, under specified patents and technology owned or controlled by Archemix to develop, make, use, sell, offer for sale, distribute for sale, import and export pharmaceutical products comprised of or derived from an anti-C5 aptamer, including ACP, for the prevention, treatment, cure or control of human indications, diseases, disorders or conditions of the eye, adnexa of the eye, orbit and optic nerve, other than certain expressly excluded applications. In connection with the C5 License Agreement, the Company paid Archemix an upfront licensing fee of $1.0 million and issued to Archemix an aggregate of 2,000,000 shares of its series A-1 preferred stock and 500,000 shares of its series B-1 preferred stock. The Company has paid Archemix an aggregate of $9.0 million in fees based on its achievement of specified clinical milestone events under the C5 License Agreement, including two milestone payments of $1.0 million and $6.0 million, respectively, triggered by the positive 12-month data from, and by completion of, the GATHER1 trial, which the Company paid in March 2020 and October 2020, respectively. Under the C5 License Agreement, for each anti-C5 aptamer product that the Company may develop under the agreement, including ACP, it is obligated to make additional payments to Archemix of up to an aggregate of $50.5 million if it achieves specified development, clinical and regulatory milestones, with $24.5 million of such payments relating to a first indication, $23.5 million of such payments relating to second and third indications and $2.5 million of such payments relating to sustained delivery applications. Under the C5 License Agreement, it is also obligated to make additional payments to Archemix of up to an aggregate of $22.5 million if it achieves specified commercial milestones based on net product sales of all anti-C5 products licensed under the agreement. It is also obligated to pay Archemix a double-digit percentage of specified non-royalty payments it may receive from any sublicensee of its rights under the C5 License Agreement. The Company is not obligated to pay Archemix a running royalty based on net product sales in connection with the C5 License Agreement. Unless earlier terminated, the C5 License Agreement will expire upon the latest of 12 years after the first commercial sale in any country of the last licensed product, the expiration of the last-to-expire valid claim of the licensed patents that covers a licensed product, and the date on which no further payments of sublicensing income are to be received by the Company. Either the Company or Archemix may terminate the C5 License Agreement if the other party materially breaches the agreement and the breach remains uncured for a specified period. Archemix may also terminate the C5 License Agreement, or may convert the Company's exclusive license under the agreement to a non-exclusive license, if the Company challenges or assists a third party in challenging the validity or enforceability of any of the patents licensed under the agreement. The Company may terminate the agreement at any time and for any or no reason effective at the end of a specified period following its written notice of termination to Archemix. License Agreement with University of Massachusetts for the miniCEP290 Program In July 2019, the Company entered into the miniCEP290 License Agreement with UMass. Under the miniCEP290 License Agreement, UMass granted it a worldwide, exclusive license under specified patent rights and specified biological materials and a non-exclusive license under specified know-how to make, have made, use, offer to sell, sell, have sold and import products for the treatment of diseases associated with mutations in the CEP290 gene, including LCA10. In July 2019, the Company issued to UMass 75,000 shares of its common stock following execution of the miniCEP290 License Agreement pursuant to an exemption from registration afforded by Section 4(a)(2) of the Securities Act. In September 2019, it paid UMass a $0.4 million upfront license fee, which was recorded as a research and development expense, and it paid UMass accrued patent prosecution expenses of approximately $18 thousand, which was recorded as a general and administrative expense. The Company has also agreed to pay UMass an annual license maintenance fee in the low double-digit thousands of dollars, which will be payable on an annual basis until the expiration of the royalty term for the licensed products. Furthermore, it has agreed to reimburse UMass for the costs and expenses of patent prosecution and maintenance related to the licensed patent rights. The Company has further agreed to pay UMass up to an aggregate of $14.75 million in cash and issue up to 75,000 shares of its common stock if it achieves specified clinical and regulatory milestones with respect to a licensed product. In addition, the Company has agreed to pay UMass up to an aggregate of $48.0 million if it achieves specified commercial sales milestones with respect to a licensed product. The Company is also obligated to pay UMass royalties at a low single-digit percentage of net sales of licensed products. Its obligation to pay royalties under the miniCEP290 License Agreement will continue on a licensed product-by-licensed product and country-by-country basis until the later of: (a) the expiration of the last-to-expire licensed patent rights covering the sale of the applicable licensed product in the country of sale, or (b) 10 years from the first commercial sale of the applicable licensed product in the country of sale. Beginning with the calendar year following receipt of marketing approval for a licensed product, it is also obligated to pay certain minimum royalties, not to exceed an amount in the mid-double-digit thousands of dollars on an annual basis, which minimum royalties are creditable against its royalty obligation with respect to net sales of licensed products due in the year the minimum royalty is paid. If the Company or any of its affiliates sublicenses any of the licensed patent rights or know-how to a third party, it will be obligated to pay UMass a high single-digit to a mid-tens percentage of the consideration received in exchange for such sublicense, with the applicable percentage based upon the stage of development of the licensed products at the time it or the applicable affiliate enters into the sublicense. If the Company receives a rare pediatric disease priority review voucher from the FDA in connection with obtaining marketing approval for a licensed product, and it subsequently uses such priority review voucher in connection with a different product candidate outside the scope of the miniCEP290 License Agreement, it will be obligated to pay UMass a low-tens percentage of the fair market value of the priority review voucher at the time of approval of such product candidate and a low-twenties percentage of the fair market value of the priority review voucher at the time of achievement of a specified commercial sales milestone for such other product candidate. In addition, if it sells such a priority review voucher to a third party, it will be obligated to pay UMass a low-thirties percentage of any consideration received from such third party in connection with such sale. The miniCEP290 License Agreement, unless earlier terminated by the Company or UMass, will expire upon the expiration of its obligation to pay royalties to UMass on net sales of licensed products. The Company may terminate the miniCEP290 License Agreement at any time for any reason upon prior written notice to UMass. It may also terminate the miniCEP290 License Agreement if UMass materially breaches the miniCEP290 License Agreement and does not cure such breach within a specified cure period. UMass may terminate the miniCEP290 License Agreement if the Company materially breaches the miniCEP290 License Agreement and does not cure such breach within a specified cure period. License Agreement with DelSiTech Ltd. On June 30, 2022, the Company entered into a license agreement (the “DelSiTech License Agreement”) with DelSiTech Ltd. (“DelSiTech”). Under the DelSiTech License Agreement, DelSiTech granted the Company a worldwide, exclusive license under specified patent rights and know-how to develop, have developed, make, have made, use, offer to sell, sell, have sold, otherwise commercialize, export and import ACP using DelSiTech’s silica-based sustained release technology for the treatment of diseases of the eye in humans (the “Licensed Product”). The Company may grant sublicenses of the licensed patent rights and know-how without DelSiTech’s consent. The Company paid DelSiTech a €1.25 million upfront license fee, which was recognized as a research and development expense during the three months ended June 30, 2022. Under the DelSiTech License Agreement, the Company is further obligated to pay DelSiTech, up to an aggregate of €35.0 million, if the Company achieves specified clinical and development milestones with respect to the Licensed Product. In addition, the Company is also obligated to pay DelSiTech up to an aggregate of €60.0 million if the Company achieves specified commercial sales milestones with respect to worldwide net sales of the Licensed Product. Due to the uncertainty of the achievement of these milestones, the Company will account for any additional payments if and when such milestones are met. The Company is also obligated to pay DelSiTech royalties at a low single-digit percentage of net sales of the Licensed Product. The royalties payable by the Company are subject to reduction under specified circumstances. The Company’s obligation to pay royalties under the DelSiTech License Agreement will continue on a country-by-country basis until the later of: (a) the expiration of the last-to-expire licensed patent rights covering the Licensed Product in the country of sale, or (b) expiration of all regulatory exclusivity for the Licensed Product in the country of sale. Future milestones and royalties will be recognized in their entirety when achieved. Unless earlier terminated by the Company or DelSiTech, the DelSiTech License Agreement will expire on a country-by-country basis upon the expiration of the Company’s obligation to pay royalties to DelSiTech on net sales of the Licensed Product. Upon expiration of the DelSiTech License Agreement, the licenses granted by DelSiTech to the Company will become fully paid up and irrevocable. The Company may terminate the agreement at any time for any reason upon 60 days’ prior written notice to DelSiTech. Either party may also terminate the DelSiTech License Agreement if the other party materially breaches the DelSiTech License Agreement and does not cure such breach within a specified cure period. Following any termination of the DelSiTech License Agreement prior to expiration of the term of the DelSiTech License Agreement, all rights to the licensed patent rights and know-how that DelSiTech granted to the Company will revert to DelSiTech, subject to the Company’s right to sell off any Licensed Product in the Company’s inventory as of the effectiveness of such termination.

Common Stock	12 Months Ended
Common Stock	Dec. 31, 2022
Equity [Abstract]
Common Stock	Common Stock December 2022 Follow-on Public Offering In December 2022, the Company completed an underwritten public offering in which the Company sold 15,352,500 shares of its common stock, which included the exercise in full of the underwriters’ option to purchase 2,002,500 shares of the Company’s common stock, at a price to the public of $22.50 per share and at a price to the underwriters of $21.15 per share. The net proceeds from the December 2022 public offering, after deducting underwriting discounts and commissions and other expenses payable by the Company totaling approximately $21.1 million, were approximately $324.3 million. October 2021 Follow-on Public Offering In October 2021, the Company completed an underwritten public offering in which the Company sold 10,350,000 shares of its common stock, which included the exercise in full of the underwriters’ option to purchase 1,350,000 shares of the Company’s common stock, at a price to the public of $16.75 per share and at a price to the underwriters of $15.745 per share. The net proceeds from the October 2021 public offering, after deducting underwriting discounts and commissions and other expenses payable by the Company totaling approximately $10.8 million, were approximately $162.6 million. July 2021 Follow-on Public Offering In July 2021, the Company completed an underwritten public offering in which the Company sold 13,397,500 shares of its common stock, which included the exercise in full of the underwriters’ option to purchase an additional 1,747,500 shares of the Company’s common stock, at a price to the public of $8.60 per share and at a price to the underwriters of $8.084 per share. The net proceeds from the July 2021 public offering, after deducting underwriting discounts and commissions and other expenses payable by the Company totaling approximately $7.4 million, were approximately $107.8 million. June 2020 Follow-on Public Offering and Private Placement In June 2020, the Company closed an underwritten public offering in which it sold 28,503,220 shares of its common stock, which includes the exercise in full of the underwriters’ option to purchase additional shares of its common stock, at a price to the public of $4.10 per share, and at a price to the underwriters of $3.854 per share. The Company also sold to certain investors in lieu of common stock, pre-funded warrants to purchase 1,914,280 shares of its common stock at a price to the public of $4.099 per share underlying each pre-funded warrant, and at a price to the underwriters of $3.853 per share underlying each pre-funded warrant. The pre-funded warrants are immediately exercisable with certain restrictions and do not expire. Concurrently with the June 2020 public offering, the Company completed a private placement exempt from the registration requirements of the Securities Act of 1933, as amended (the "Securities Act"), in which it sold 8,649,453 shares of its common stock to affiliates of Vivo Capital, LLC and Samsara BioCapital, LP (the "Private Placement Purchasers"), at a purchase price equal to $4.10 per share, which is the price to the public in the public offering. The shares in the private placement were issued pursuant to a stock purchase agreement entered into among the Company and the Private Placement Purchasers. The net proceeds from the public offering and private placement, after deducting underwriting discounts, placement agent fees and other offering expenses of approximately $10.1 million, were approximately $150.1 million. The Company evaluated the pre-funded warrants for liability or equity classification in accordance with the provisions of ASC 480, Distinguishing Liabilities from Equity, and ASC 815-40, Derivatives and Hedging. Based on the provisions governing the pre-funded warrants in the applicable agreement, the Company determined that the pre-funded warrants meet the criteria required to be classified as an equity award subject to the guidance in ASC 815-10 and 815-40 and should effectively be treated as outstanding common shares in both basic and diluted EPS calculations.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Commitments and Contingencies - Legal Proceedings [WH to update] (Details) - USD ($) $ in Millions	Jun. 22, 2021	Apr. 23, 2021	Sep. 08, 2021
Loss Contingencies [Line Items]
Litigation stay period	60 days	10 days
Settled Litigation
Loss Contingencies [Line Items]
Settlement to be paid			$ 29

Cash, Cash Equivalents and Available-for-Sale Securities

12 Months Ended

Dec. 31, 2022

Cash and Cash Equivalents [Abstract]

Cash, Cash Equivalents and Available-for-Sale Securities

As of December 31, 2022 and December 31, 2021 the Company had cash and cash equivalents of approximately $476.3 million and $261.4 million, respectively. Cash and cash equivalents at December 31, 2022 and December 31, 2021 included cash of $0.6 million and $9.9 million, respectively. As of December 31, 2022 and December 31, 2021, cash and cash equivalents also included $475.7 million and $251.5 million, respectively, of investments in money market funds.

As of December 31, 2022 and December 31, 2021, the Company held available-for-sale securities of approximately $170.5 million and $120.3 million, respectively, all of which have maturities of less than one year.

As of December 31, 2022, the Company determined that there were no credit losses in its available-for-sale securities. Factors considered in determining whether a loss resulted from a credit loss or other factors included the length of time and extent to which the investment’s fair value has been less than the cost basis, the financial condition and near-term prospects of the investee, the extent of the loss related to credit of the issuer, the expected cash flows from the security, the Company’s intent to sell the security, and whether or not the Company will be required to sell the security before the recovery of its amortized cost.

The Company classifies these securities as available-for-sale. However, the Company has not sold and does not currently intend to sell its investments and the Company believes it is more likely than not that the Company will recover the carrying value of these investments.

Available-for-sale securities, including carrying value and estimated fair values, are summarized as follows:


	As of December 31, 2022
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
U.S. Treasury securities	$	27,481	$	3	$	(61)	$	27,423
Corporate debt securities	109,248		—		(119)		109,129
U.S. government agency securities	9,644		25		—		9,669
Asset-backed securities	19,360		—		(63)		19,297
Supranational securities	5,027		—		(14)		5,013
Total	$	170,760	$	28	$	(257)	$	170,531


	As of December 31, 2021
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses	Fair Value
U.S. Treasury securities	$	18,202	$	—	(16)	$	18,185
Corporate debt securities	82,138		—		(57)	82,081
Asset-backed securities	16,008		—		(14)	15,995

Supranational securities	4,044		—		(3)	4,041
Total	120,392		—		(90)	120,302

Loan and Security Agreement - Interest Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Amortization of debt issuance costs	$ 466	$ 0	$ 0
2022 Term Loan
Debt Instrument [Line Items]
Interest expense for 2022 Term Loan Facility	2,486
Accretion of end of term charge	215
Amortization of debt issuance costs	251
Total interest expense related to 2022 Term Loan Facility	$ 2,952

Cash, Cash Equivalents and Available-for-Sale Securities (Tables)

12 Months Ended

Dec. 31, 2022

Cash and Cash Equivalents [Abstract]

Schedule of Available-for-Sale Securities

Available-for-sale securities, including carrying value and estimated fair values, are summarized as follows:


	As of December 31, 2022
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
U.S. Treasury securities	$	27,481	$	3	$	(61)	$	27,423
Corporate debt securities	109,248		—		(119)		109,129
U.S. government agency securities	9,644		25		—		9,669
Asset-backed securities	19,360		—		(63)		19,297
Supranational securities	5,027		—		(14)		5,013
Total	$	170,760	$	28	$	(257)	$	170,531


	As of December 31, 2021
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses	Fair Value
U.S. Treasury securities	$	18,202	$	—	(16)	$	18,185
Corporate debt securities	82,138		—		(57)	82,081
Asset-backed securities	16,008		—		(14)	15,995

Supranational securities	4,044		—		(3)	4,041
Total	120,392		—		(90)	120,302

Fair Value Measurements - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - Recurring Basis - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Quoted prices in active markets for identical assets (Level 1) \| Investments in money market funds
Fair Value Measurements
Investments in money market funds	$ 475,689	$ 251,488
Quoted prices in active markets for identical assets (Level 1) \| Investments in U.S. Treasury securities
Fair Value Measurements
Investments, fair value disclosure	27,423	18,185
Quoted prices in active markets for identical assets (Level 1) \| Investments in corporate debt securities
Fair Value Measurements
Investments, fair value disclosure	0	0
Quoted prices in active markets for identical assets (Level 1) \| Investments in U.S. government agency securities
Fair Value Measurements
Investments, fair value disclosure	0
Quoted prices in active markets for identical assets (Level 1) \| Investments in asset-backed securities
Fair Value Measurements
Investments, fair value disclosure	0	0
Quoted prices in active markets for identical assets (Level 1) \| Investments in supranational securities
Fair Value Measurements
Investments, fair value disclosure	0	0
Significant other observable inputs (Level 2) \| Investments in money market funds
Fair Value Measurements
Investments in money market funds	0	0
Significant other observable inputs (Level 2) \| Investments in U.S. Treasury securities
Fair Value Measurements
Investments, fair value disclosure	0	0
Significant other observable inputs (Level 2) \| Investments in corporate debt securities
Fair Value Measurements
Investments, fair value disclosure	109,129	82,081
Significant other observable inputs (Level 2) \| Investments in U.S. government agency securities
Fair Value Measurements
Investments, fair value disclosure	9,669
Significant other observable inputs (Level 2) \| Investments in asset-backed securities
Fair Value Measurements
Investments, fair value disclosure	19,297	15,995
Significant other observable inputs (Level 2) \| Investments in supranational securities
Fair Value Measurements
Investments, fair value disclosure	5,013	4,041
Significant unobservable inputs (Level 3) \| Investments in money market funds
Fair Value Measurements
Investments in money market funds	0	0
Significant unobservable inputs (Level 3) \| Investments in U.S. Treasury securities
Fair Value Measurements
Investments, fair value disclosure	0	0
Significant unobservable inputs (Level 3) \| Investments in corporate debt securities
Fair Value Measurements
Investments, fair value disclosure	0	0
Significant unobservable inputs (Level 3) \| Investments in U.S. government agency securities
Fair Value Measurements
Investments, fair value disclosure	0
Significant unobservable inputs (Level 3) \| Investments in asset-backed securities
Fair Value Measurements
Investments, fair value disclosure	0	0
Significant unobservable inputs (Level 3) \| Investments in supranational securities
Fair Value Measurements
Investments, fair value disclosure	$ 0	$ 0

Stock-Based Compensation and Compensation Plans

12 Months Ended

Dec. 31, 2022

Share-Based Payment Arrangement [Abstract]

Stock-Based Compensation and Compensation Plans

Stock-Based Compensation and Compensation Plans The Company adopted its 2007 Stock Incentive Plan (the "2007 Plan") for employees, non-employee directors and consultants for the purpose of advancing the interests of the Company's stockholders by enhancing its ability to attract, retain and motivate persons who are expected to make important contributions to the Company. The 2007 Plan provided for the granting of stock option awards, RSUs, and other stock-based and cash-based awards. Following the effectiveness of the 2013

Stock Incentive Plan described below in connection with the closing of the Company's initial public offering, the Company is no longer granting additional awards under the 2007 Plan.

In August 2013, the Company's board of directors adopted, and the Company's stockholders approved, the 2013 Stock Incentive Plan (the "2013 Plan"), which became effective immediately prior to the closing of the Company's initial public offering. In June 2015, the Company’s board of directors adopted a first amendment to the 2013 Plan. The 2013 Plan provides for the grant of incentive stock options, nonstatutory stock options, stock appreciation rights, RSUs, restricted stock awards and other stock-based awards. Upon the effectiveness of the 2013 Plan, the number of shares of the Company's common stock that were reserved for issuance under the 2013 Plan was the sum of (1) a number of shares (up to a maximum of approximately 3,359,641 shares) that is equal to the sum of 739,317 shares (the number of shares of the Company's common stock then available for issuance under the 2007 Plan), and such number of shares of the Company's common stock that are subject to outstanding awards under the 2007 Plan that expire, terminate or are otherwise surrendered, canceled, forfeited or repurchased by the Company at their original issuance price pursuant to a contractual repurchase right, plus (2) an annual increase, to be added the first business day of each fiscal year, beginning with the fiscal year ending December 31, 2014 and continuing until, and including, the fiscal year ending December 31, 2023, equal to the lowest of 2,542,372 shares of the Company's common stock, 4% of the number of shares of the Company's common stock outstanding on the first day of the fiscal year and an amount determined by its board of directors. The Company's employees, officers, directors, consultants and advisors are eligible to receive awards under the 2013 Plan. However, incentive stock options may only be granted to employees of the Company.

Annual increases under the evergreen provisions of the 2013 Plan have resulted in the addition of an aggregate of approximately 18,166,000 additional shares to the 2013 Plan, including for 2023, an increase of approximately 2,542,000 shares. As of December 31, 2022, the Company had approximately 166,000 shares available for grant under the 2013 Plan.

In October 2019, the Company's board of directors adopted the 2019 Inducement Stock Incentive Plan (the “2019 Inducement Plan”) to reserve 1,000,000 shares of its common stock to be used exclusively for grants of awards to individuals that were not previously employees or directors of the Company as a material inducement to such individuals’ entry into employment with the Company within the meaning of Rule 5635(c)(4) of the Nasdaq Listing Rules. In March 2020, the Company's board of directors amended the 2019 Inducement Plan to reserve an additional 1,000,000 shares of its common stock for issuance under the plan and in February 2021, the Company's board of directors further amended the 2019 Inducement Plan to reserve an additional 600,000 shares of its common stock for issuance under the plan. In September 2021, December 2021 and May 2022, the Company's board of directors further amended the 2019 Inducement Plan to reserve an additional 1,000,000 shares of common stock for issuance under the plan during each of the instances. In February 2023, the Company's board of directors further amended the 2019 Inducement Plan to reserve an additional 2,000,000 shares of common stock for issuance under the plan. The terms and conditions of the 2019 Inducement Plan are substantially similar to those of the 2013 Plan. As of December 31, 2022, the Company had approximately 791,000 shares available for grant under the 2019 Inducement Plan.

In April 2016, the board of directors adopted the ESPP pursuant to which the Company may sell up to an aggregate of 1,000,000 shares of common stock. The ESPP was approved by the Company’s stockholders in June 2016. The ESPP allows eligible employees to purchase common stock at a price per share equal to 85% of the lower of the fair market value of the common stock at the beginning or end of each six month offering period during the term of the ESPP. The first offering period began in September 2016. In December 2022, the ESPP was amended to permit employees to enroll any of four times each year.

A summary of the stock option activity, weighted average exercise prices, options outstanding and exercisable as of December 31, 2022, 2021 and 2020 is as follows (in thousands except weighted average exercise price):


	Years ended December 31,
	2022			2021			2020
	Common Stock Options	Weighted Average Exercise Price		Common Stock Options	Weighted Average Exercise Price		Common Stock Options	Weighted Average Exercise Price
Outstanding, December 31, 2021	10,861	$	10.94	8,928	$	9.22	6,780	$	10.89
Granted	3,812	$	19.48	3,204	$	13.03	2,630	$	6.10
Exercised	(2,066)	$	3.84	(646)	$	2.80	(109)	$	2.89
Expired or forfeited	(204)	$	14.08	(625)	$	8.87	(373)	$	19.49
Outstanding, December 31, 2022	12,403	$	14.70	10,861	$	10.94	8,928	$	9.22


	Years ended December 31,
	2022		2021		2020
Options exercisable at December 31, 2022	5,457		5,584		4,462
Weighted average grant date fair value (per share) of options granted during the period	$	13.57	$	10.53	$	4.83

As of December 31, 2022, there were approximately 11,847,000 options outstanding, net of estimated forfeitures, that had vested or are expected to vest. The weighted-average exercise price of these options was $14.66 per option; the weighted-average remaining contractual life of these options was 7.5 years; and the aggregate intrinsic value of these options was approximately $106.2 million. A summary of the stock options outstanding and exercisable as of December 31, 2022 is as follows (in thousands except exercise prices and weighted average exercise price):


			December 31, 2022
			Options Outstanding			Options Exercisable
Range of Exercise Prices	Total Options Outstanding		Weighted Average Remaining Life (Years)	Weighted Average Exercise Price		Number Exercisable		Weighted Average Exercise Price
$1.20-$2.96	1,266		5.3	$	2.43	1,263		$	2.43
$2.97-$4.88	1,280		6.1	$	4.02	1,021		$	4.08
$4.89-$8.07	2,319		7.8	$	6.73	1,171		$	6.58
$8.08-$15.00	2,644		8.6	$	12.88	705		$	12.67
$15.01-$73.22	4,894		7.9	$	25.43	1,297		$	38.68
	12,403		7.6	$	14.70	5,457		$	13.57

Aggregate Intrinsic Value	$	109,659				$	66,270

Cash proceeds from, and the aggregate intrinsic value of, stock options exercised during the years ended December 31, 2022, 2021 and 2020, respectively, were as follows:


	Years ended December 31,
	2022		2021		2020
Cash proceeds from options exercised	$	7,943	$	1,808	$	314
Aggregate intrinsic value of options exercised	$	23,628	$	4,997	$	393

In connection with stock option awards granted to employees, non-employees directors and certain other individuals, the Company recognized approximately $16.1 million, $6.5 million and $4.7 million in share-based compensation expense during the years ended December 31, 2022, 2021 and 2020, respectively, net of expected forfeitures. As of December 31, 2022, there were approximately $66.9 million of unrecognized compensation costs, net of estimated forfeitures, related to stock option awards grants, which are expected to be recognized over a remaining weighted average period of 3.2 years.

The following table presents a summary of the Company's outstanding RSU awards granted as of December 31, 2022 (in thousands except weighted average grant-date fair value)


	Restricted Stock Units	Weighted Average Grant-Date Fair Value
Outstanding, December 31, 2021	2,246	$	9.82
Awarded	1,565	$	19.15
Vested	(739)	$	7.81
Expired or forfeited	(46)	$	10.96
Outstanding, December 31, 2022	3,026	$	15.12

As of December 31, 2022, there were approximately 2,788,000 RSUs outstanding, net of estimated forfeitures, that are expected to vest. The weighted-average fair value of these RSUs was $15.12 per share; and the aggregate intrinsic value of these RSUs was approximately $59.7 million.

In connection with RSUs granted to employees, non-employees directors and certain other individuals, the Company recognized approximately $10.2 million, $4.6 million and $3.3 million in share-based compensation expense during the years ended December 31, 2022, 2021, and 2020, respectively, net of expected forfeitures. As of December 31, 2022, there was approximately $36.4 million of unrecognized compensation costs, net of estimated forfeitures, related to RSU grants, which are expected to be recognized over a remaining weighted average period of 3.3 years. The total fair value of the RSUs that vested during the year ended December 31, 2022, was $5.8 million.

In connection with the ESPP made available to employees, the Company recognized approximately $0.4 million and $0.2 million of share-based compensation expense during the years ended December 31, 2022, and December 31, 2021, respectively, net of expected forfeitures. As of December 31, 2022, there was $0.1 million of unrecognized compensation costs, net of estimated forfeitures, related to the ESPP, which are expected to be recognized over 0.2 years. There were 41,016 and 51,951 shares of common stock issued under the ESPP during the year ended December 31, 2022, and 2021, respectively. Cash proceeds from ESPP purchases were approximately $0.5 million and $0.3 million during the year ended December 31, 2022, and 2021, respectively. As of December 31, 2022, 712,394 shares were available for future purchases under the ESPP.

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Statement of Comprehensive Income [Abstract]
Net loss	$ (185,211)	$ (114,522)	$ (84,547)
Other comprehensive income
Unrealized (loss) gain on available-for-sale securities, net of tax	(139)	(93)	3
Other comprehensive (loss) income	(139)	(93)	3
Comprehensive loss	$ (185,350)	$ (114,615)	$ (84,544)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

Summary of Significant Accounting Policies (Policies)	12 Months Ended
Summary of Significant Accounting Policies (Policies)	Dec. 31, 2022
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation and Consolidation The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America ("GAAP") and include all adjustments necessary for the fair presentation of the Company's financial position for the periods presented.
Basis of Consolidation	The consolidated financial statements include the accounts of the Company and its subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.
Segment and geographic information	Segment and geographic information Operating segments are defined as components of an enterprise about which separate discrete information is available for evaluation by the chief operating decision maker, or decision making group, in deciding how to allocate resources and in assessing performance. The Company views its operations and manages its business in one operating and reporting segment.
Use of Estimates	Use of Estimates The preparation of financial statements and related disclosures in conformity with GAAP requires management to make estimates and judgments that affect the amounts reported in the financial statements and accompanying notes. The Company bases its estimates and judgments on historical experience and on various other assumptions that it believes are reasonable under the circumstances. The amounts of assets and liabilities reported in the Company's Consolidated Balance Sheets and the amount of expenses reported for each of the periods presented are affected by estimates and assumptions, which are used for, but not limited to, accounting for research and development costs and accounting for share-based compensation. Actual results could differ from those estimates.
Cash and Cash Equivalents	Cash and Cash Equivalents and Available-for-Sale Securities The Company considers all highly liquid investments with an original maturity of 90 days or less when purchased to be cash equivalents. The carrying amounts reported in the Company's Consolidated Balance Sheets for cash and cash equivalents are valued at cost, which approximates their fair value.
Available-for-Sale Securities	The Company considers debt securities with original maturities of greater than 90 days to be available-for-sale securities. Available-for-sale securities with original maturities of greater than one year are recorded as non-current assets. Available-for-sale securities are recorded at fair value and unrealized gains and losses are recorded within other comprehensive income. On a quarterly basis, the Company reviews the status of each security in an unrealized loss position, to evaluate the existence of potential credit losses. The Company first considers whether it intends to sell, or if it is more likely than not that the Company will be required to sell the security before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the security’s amortized cost basis is written down to fair value through income. For securities that do not meet this criteria, the Company considers a number of factors to determine if the decline in fair value has resulted from credit losses or other factors, including but not limited to: (1) the extent of the decline; (2) changes to the rating of the security by a rating agency; (3) any adverse conditions specific to the security; and (4) other market conditions that may affect the fair value of the security. If this assessment indicates that a credit loss exists and the present value of cash flows expected to be collected is less than the amortized cost basis, an allowance for credit losses is required for the credit loss. Any impairment that has not been recorded through an allowance for credit losses is recognized in other comprehensive income.
Concentration of Credit Risk	Concentration of Credit Risk The Company's financial instruments that are exposed to concentration of credit risk consist primarily of cash, cash equivalents and available-for-sale securities. The Company maintains its cash in bank accounts, the balances of which generally exceed federally insured limits. The Company maintains its cash equivalents and available-for-sale securities in investments in money market funds, in U.S. Treasury securities, U.S. Government Agency securities, investment-grade corporate debt securities, asset-backed securities and debt instruments issued by foreign governments with original maturities of 90 days or less. The Company believes it is not exposed to significant credit risk on its cash, cash equivalents and available-for-sale securities.
Concentration of Suppliers	Concentration of Suppliers The Company historically relied upon a single third-party manufacturer to provide the drug substance for ACP on a purchase order basis. The Company also historically relied upon a single third-party manufacturer to provide fill/finish services for clinical supplies of ACP. The Company has engaged one additional third-party manufacturer to provide drug substance for ACP and one additional third-party manufacturer to provide fill/finish services for clinical supplies of ACP. In addition, the Company currently relies upon a single third-party supplier to supply on a purchase order basis the polyethylene glycol starting material used to manufacture ACP. Furthermore, the Company and its contract manufacturers currently rely upon sole-source suppliers of certain raw materials and other specialized components of production used in the manufacture and fill/finish of ACP. The Company currently relies upon a single third-party contract manufacturer to provide the drug substance for IC-500 for preclinical toxicology studies and early-stage clinical trials and a single third-party contract manufacturer to conduct fill/finish services for IC-500 drug product. If the Company’s third-party manufacturers or fill/finish service providers should become unavailable to the Company for any reason, including as a result of capacity constraints, different business objectives, financial difficulties, insolvency or the impact of COVID-19, the Company believes that there are a limited number of potential replacement manufacturers, and the Company likely would incur added costs and delays in identifying or qualifying such replacements.
Equity Investments	Equity Investments The Company holds investments in equity securities without a readily determinable fair value. Equity investments without a readily determinable fair value are recognized at fair value and are adjusted for observable price changes, or when qualitative assessments indicate that impairment exists, which is recorded in other income (loss).
Financial Instruments	Financial Instruments Cash equivalents are reflected in the accompanying financial statements at fair value. The carrying amount of accounts payable and accrued expenses, including accrued research and development expenses, approximates fair value due to the short-term nature of those instruments. The carrying amount of the Company's term loan approximates fair value due to the variable interest rate nature of the debt. Accounting Standards Codification, or ASC 820, Fair Value Measurements and Disclosures, defines fair value as the price that would be received to sell an asset, or paid to transfer a liability, in the principal or most advantageous market in an orderly transaction between market participants on the measurement date. The fair value standard also establishes a three-level hierarchy, which requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The Company reviews investments on a periodic basis for other than temporary impairments. This review is subjective as it requires management to evaluate whether an event or change in circumstances has occurred in the period that may have a significant adverse effect on the fair value of the investment. The Company uses the market approach to measure fair value for its cash, cash equivalents and available-for-sale financial assets. The market approach uses prices and other relevant information generated by market transactions involving identical or comparable assets. The valuation hierarchy is based upon the transparency of inputs to the valuation of an asset or liability on the measurement date. The three levels are defined as follows: •Level 1—inputs to the valuation methodology are quoted prices (unadjusted) for an identical asset or liability in an active market. The Company's Level 1 assets consist of investments in money market funds and U.S. Treasury securities. •Level 2—inputs to the valuation methodology include quoted prices for a similar asset or liability in an active market or model-derived valuations in which all significant inputs are observable for substantially the full term of the asset or liability. The Company's Level 2 assets consist of investments in investment-grade corporate debt securities. •Level 3—inputs to the valuation methodology are unobservable and significant to the fair value measurement of the asset or liability. The Company does not hold any assets that are measured using Level 3 inputs.
Foreign Currency Translation	Foreign Currency Translation The Company considers the U.S. dollar to be its functional currency. Expenses denominated in foreign currencies are translated at the exchange rate on the date the expense is incurred. The effect of exchange rate fluctuations on translating foreign currency assets and liabilities into U.S. dollars is included in the Consolidated Statements of Operations and Comprehensive Loss. Foreign exchange transaction gains and losses are included in the results of operations and are not material in the Company's financial statements.
Income Taxes	Income Taxes The Company utilizes the liability method of accounting for deferred income taxes, as set forth in ASC 740, Income Taxes. Under this method, deferred tax assets and liabilities are recognized for the expected future tax consequences of temporary differences between the carrying amounts and the tax basis of assets and liabilities. A valuation allowance is established against deferred tax assets when, based on the weight of available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. The Company's policy is to record interest and penalties on uncertain tax positions as income tax expense.
Leases	Leases The Company determines if an arrangement contains a lease at inception. For arrangements where the Company is the lessee, it recognizes a right-of-use ("ROU") asset and operating lease liability on the Company's Consolidated Balance Sheet. ROU assets represent the Company's right to use the underlying asset for the lease term and the lease obligation represents the Company's commitment to make the lease payments arising from the lease. Right-of-use lease assets and obligations are recognized at the commencement date based on the present value of remaining lease payments over the lease term. As the Company’s leases do not provide an implicit discount rate, the Company has used an estimated incremental borrowing rate based on the information available at the commencement date in determining the present value of lease payments. ROU assets include any lease payments made prior to commencement and excludes any lease incentives. The lease term may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Operating lease expense is recognized on a straight-line basis over the lease term, subject to any changes in the lease or expectations regarding the terms. Variable lease costs such as common area costs and property taxes are expensed as incurred. For all office lease agreements the Company combines lease and nonlease components. Leases with an initial term of 12 months or less are not recorded on the Company's Consolidated Balance Sheet.
Property and Equipment	Property and Equipment Property and equipment, which consists mainly of clinical equipment, laboratory equipment, computers, software, other office equipment, automobiles and leasehold improvements, are carried at cost less accumulated depreciation. Depreciation is computed over the estimated useful lives of the respective assets, generally three to ten years, using the straight-line method. Amortization of leasehold improvements is recorded over the shorter of the lease term or estimated useful life of the related asset.
Research and Development	Research and Development The Company's research and development expenses primarily consist of costs associated with the manufacturing, development, and preclinical and clinical testing of the Company's product candidates and costs associated with its gene therapy research programs. The Company's research and development expenses consist of: •external research and development expenses incurred under arrangements with third parties, such as contract research organizations ("CROs") and contract development and manufacturing organizations ("CDMOs") and other vendors for the production and analysis of drug substance and drug product; and •employee-related expenses for employees dedicated to research and development activities, including salaries, benefits and share-based compensation expense. Research and development expenses also include costs of acquired product licenses, in-process research and development, and related technology rights where there is no alternative future use, costs of prototypes used in research and development, consultant fees and amounts paid to collaborators. All research and development expenses are charged to operations as incurred in accordance with ASC 730, Research and Development. The Company accounts for non-refundable advance payments for goods and services that will be used in future research and development activities as expenses when the service has been performed or when the goods have been received, rather than when the payment is made.
Share-Based Compensation	Share-Based Compensation The Company follows the provisions of ASC 718, Compensation—Stock Compensation, which requires the measurement and recognition of compensation expense for all share-based payment awards made to employees, non-employee directors and certain other individuals, including employee stock options, restricted stock units (“RSUs”) and options granted to employees to purchase shares under the 2016 Employee Stock Purchase Plan (the “ESPP”). Share-based compensation expense is based on the grant date fair value estimated in accordance with the provisions of ASC 718 and is generally recognized as an expense over the requisite service period, net of estimated forfeitures. For grants containing performance-based vesting provisions, expense is recognized over the estimated achievement period only when the performance-based milestone is deemed probable of achievement. If performance-based milestones are later determined not to be probable of achievement, then all previously recorded stock-based compensation expense associated with such options will be reversed during the period in which the Company makes this determination. For grants containing a market condition, the Company estimated the fair value using a Monte Carlo simulation model which takes into consideration different stock price paths. The Company recognizes compensation expense for the market award on a straight-line basis over the derived service period. Compensation expense is recognized for market awards, so long as the requisite service is provided. The Company estimates forfeitures at the time of grant and revises those estimates in subsequent periods if actual forfeitures differ from its estimates. The Company uses historical data to estimate pre-vesting forfeitures and record share-based compensation expense only for those awards that are expected to vest. To the extent that actual forfeitures differ from the Company's estimates, the difference is recorded as a cumulative adjustment in the period the estimates were revised.
Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements The Company has evaluated recent accounting pronouncements through the date the financial statements were issued and filed with the SEC and believes that there are none that will have a material impact on the Company’s financial statements.

Fair Value Measurements - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Fair Value Measurements
Proceeds from sale of assets		$ 500	$ 0	$ 0
Purchase agreement fair value of shares, recognized		$ 1,869	$ 0	$ 0
Opus Genetics Inc
Fair Value Measurements
Proceeds from sale of assets	$ 500
Opus Genetics Inc \| Significant unobservable inputs (Level 3)
Fair Value Measurements
Purchase agreement fair value of shares, recognized	1,900
Opus Genetics Inc \| Contingent Development And Regulatory Milestone Payments
Fair Value Measurements
Contingent development and regulatory milestone amount	12,800
Opus Genetics Inc \| Sales Milestone Payments
Fair Value Measurements
Contingent development and regulatory milestone amount	$ 98,900
Series Seed Preferred Stock \| Opus Genetics Inc
Fair Value Measurements
Purchase agreement consideration (in shares)	2,632,720
Purchase agreement consideration (in us dollar per share)	$ 0.00001

Stock-Based Compensation and Compensation Plans - Schedule of Cash Proceeds From and Aggregate Intrinsic Value of Stock Options Exercised (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-Based Payment Arrangement [Abstract]
Cash proceeds from options exercised	$ 7,943	$ 1,808	$ 314
Aggregate intrinsic value of options exercised	$ 23,628	$ 4,997	$ 393

Business (Details) - Avacincaptad Pegol - patient	1 Months Ended
Business (Details) - Avacincaptad Pegol - patient	Sep. 30, 2022	Oct. 31, 2019
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Patients in trial	448	286
Reduction in mean rate of growth	14.30%	27.70%
Reduction in mean rate of growth without using square root transformation	17.70%	35.40%

Summary of Significant Accounting Policies - Share-Based Compensation (Details) - shares	1 Months Ended		12 Months Ended
	Jun. 30, 2016	Apr. 30, 2016	Dec. 31, 2022
Share-Based Compensation
Expected dividend yield			0.00%
ESPP
Share-Based Compensation
Withholding period	6 months	6 months
ESPP \| Maximum
Share-Based Compensation
Number of shares reserved for issuance under the plan up to (in shares)		1,000,000

Summary of Significant Accounting Policies - Schedule of Share-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-Based Compensation
Share-based compensation expense	$ 26,676	$ 11,245	$ 8,323
Research and development
Share-Based Compensation
Share-based compensation expense	11,865	6,522	4,166
General and administrative
Share-Based Compensation
Share-based compensation expense	$ 14,811	$ 4,723	$ 4,157

Loan and Security Agreement

12 Months Ended

Dec. 31, 2022

Debt Disclosure [Abstract]

Loan and Security Agreement

Loan and Security AgreementOn July 26, 2022 (the “Closing Date”), the Company and certain of its subsidiaries (the “Subsidiary Borrowers”) entered into a Loan and Security Agreement (the “Loan Agreement”) with Hercules Capital, Inc. (“Hercules”), in its capacity as administrative agent and collateral agent (in such capacity, the “Agent”) and as a lender, Silicon Valley Bank (“SVB”) and certain other financial institutions that from time to time become parties to the Loan Agreement as lenders (collectively, the “Lenders”). The Loan Agreement provides for term loans in an aggregate principal amount of up to $250.0 million under multiple tranches (the “2022 Term Loan Facility”), available as follows: (i) a term loan advance in the amount of $50.0 million, which was drawn on the Closing Date; (ii) a second tranche consisting of term loan advances in the aggregate principal amount of $50.0 million which was drawn in December 2022; (iii) a third tranche consisting of term loan advances in the aggregate principal amount of $25.0 million, available at the Company’s option through September 30, 2023; (iv) subject to FDA

approval of ACP in GA with a label generally consistent with that sought in the Company’s NDA (“Milestone 3”), a fourth tranche consisting of term loan advances in the aggregate principal amount of $75.0 million, available at the Company’s option beginning on the date that Milestone 3 is achieved and continuing through the earlier of (x) September 30, 2024 and (y) the date that is 90 days after the date that Milestone 3 is achieved; and (v) subject to approval by the Lenders’ investment committee in its discretion, a fifth tranche of additional term loans in an aggregate principal amount of up to $50.0 million, available on or before the Amortization Date (as defined below). With the exception of the first $50.0 million tranche drawn on the Closing Date, each of the tranches may be drawn down in $5.0 million increments at the Company's election upon achievement of the relevant conditions specified in the Loan Agreement. The Company has agreed to use the proceeds of the 2022 Term Loan Facility for working capital and general corporate purposes.

Notwithstanding limitations and restrictions imposed by covenants in the Loan Agreement, the Company is permitted to engage in certain specified transactions. For example, the terms of the Loan Agreement provide that the Company may issue convertible notes in an aggregate principal amount of not more than $400.0 million, provided that such notes are unsecured, have a maturity date no earlier than six months following the Maturity Date (as defined below), and meet certain other conditions. The Loan Agreement also provides that the Company may enter into royalty interest financing transactions that are subordinated to the 2022 Term Loan Facility, have a maturity date no earlier than six months following the Maturity Date, and meet certain other conditions. Following the achievement of Milestone 3, the Loan Agreement also provides for a possible additional revolving credit facility of up to $50.0 million, which will be formula-based and backed by the Company’s accounts receivables. This potential revolving credit facility is not an existing facility under the Loan Agreement, is not committed, and is subject to agreement among the Company and the Lenders. The Company may enter into non-exclusive and certain specified exclusive licensing arrangements with respect to core intellectual property and non-exclusive and exclusive licensing arrangements or otherwise transfer non-core intellectual property without the consent of the Lenders. The Company may also enter into certain permitted acquisitions, subject to a limit on total cash consideration for acquisitions consummated during specified periods. Additionally, the Company must provide the Lenders the opportunity to invest up to $10.0 million in any equity financing, subject to certain exclusions, that is broadly marketed to multiple investors and in which the Company receives net cash proceeds of $75.0 million or more in any one or series of related financings (or in the case of any such equity financing that is a registered offering, use its commercially reasonable efforts to provide such opportunity to the Lenders).

The 2022 Term Loan Facility will mature on August 1, 2027 (the “Maturity Date”). The outstanding principal balance of the 2022 Term Loan Facility bears interest at a floating interest rate per annum equal to the greater of either (i) (x) the lesser of the Wall Street Journal prime rate and 6.25% plus (y) 4.00% or (ii) 8.75%. The per annum interest rate is capped at 10.25%. Accrued interest is payable monthly following the funding of each term loan. The Company may make payments of interest only, without any loan amortization payments, for a period of 42 months following the Closing Date, which period may be extended to the Maturity Date if (i) Milestone 3 has been achieved and (ii) no default or event of default exists under the Loan Agreement. At the end of the interest only period (the “Amortization Date”), the Company is required to begin repayment of the outstanding principal of the 2022 Term Loan Facility in equal monthly installments.

As collateral for the obligations under the 2022 Term Loan Facility, the Company has granted to the Agent for the benefit of the Lenders a senior security interest in substantially all of its and each Subsidiary Borrower’s property, inclusive of intellectual property, with certain limited exceptions set forth in the Loan Agreement.

The Loan Agreement contains customary closing and commitment fees, prepayment fees and provisions, events of default and representations, warranties and affirmative and negative covenants, including a financial covenant requiring the Company to maintain certain levels of cash in accounts subject to a control agreement in favor of the Agent (the “Qualified Cash”) during the period commencing on May 15, 2023 through August 14, 2024. Commencing on August 15, 2024, the Company will also be required to maintain a certain minimum amount of trailing six-month net product revenue from the sale of ACP, tested on a quarterly basis. The revenue covenant will be waived at any time at which the Company (x) (i) maintains a market capitalization in excess of $600.0 million and (ii) maintains Qualified Cash in an amount greater than or equal to fifty percent (50%) of the outstanding 2022 Term Loan Facility at such time or (y) maintains Qualified Cash in an amount greater than or equal to ninety percent (90%) of the outstanding 2022 Term Loan Facility at such time. Upon the occurrence of an event of default, including a material adverse effect, subject to certain exceptions, on the business, operations, properties, assets or financial condition of the Company and the Subsidiary Borrowers taken as a whole, and subject to any specified cure

periods, all amounts owed by the Company may be declared immediately due and payable by the Lenders. As of December 31, 2022, the Company was in compliance with all applicable covenants under the Loan Agreement.

In addition, the Company is required to make a final payment fee (the “End of Term Charge”) upon the earlier of (i) the Maturity Date or (ii) the date the Company prepays, in full or in part, the outstanding principal balance of the 2022 Term Loan Facility. The End of Term Charge is 4.25% of the aggregate original principal amount of the term loans repaid or prepaid under the Loan Agreement.

The Company may, at its option, prepay the term loans in full or in part, subject to a prepayment penalty equal to (i) 2.0% of the principal amount prepaid if the prepayment occurs prior to the first anniversary of the Closing Date, (ii) 1.5% of the principal amount prepaid if the prepayment occurs on or after the first anniversary and prior to the second anniversary of the Closing Date, and (iii) 0.75% of the principal amount prepaid if the prepayment occurs on or after the second anniversary and prior to the third anniversary of the Closing Date.

During the year ended December 31, 2022, the Company recognized interest expense on its Consolidated Statements of Operations and Comprehensive Loss in connection with the 2022 Term Loan Facility as follows:


	Year ended December 31, 2022
Interest expense for 2022 Term Loan Facility	$	2,486
Accretion of end of term charge	215
Amortization of debt issuance costs	251
Total interest expense related to 2022 Term Loan Facility	$	2,952

The principal balance of the 2022 Term Loan Facility and related accretion and amortization as of December 31, 2022, were as follows:


	December 31, 2022
2022 Term Loan Facility, gross (amount drawn)	$	100,000
Debt issuance costs	(3,898)
Accretion of end of term charge	215
Accumulated amortization of debt issuance costs	251
2022 Term Loan Facility, net	$	96,568

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

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+ Details

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2022

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

Basis of Presentation and Consolidation

The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America ("GAAP") and include all adjustments necessary for the fair presentation of the Company's financial position for the periods presented. The consolidated financial statements include the accounts of the Company and its subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.

Segment and geographic information

Operating segments are defined as components of an enterprise about which separate discrete information is available for evaluation by the chief operating decision maker, or decision making group, in deciding how to allocate resources and in assessing performance. The Company views its operations and manages its business in one operating and reporting segment.

Use of Estimates

The preparation of financial statements and related disclosures in conformity with GAAP requires management to make estimates and judgments that affect the amounts reported in the financial statements and accompanying notes. The Company bases its estimates and judgments on historical experience and on various other assumptions that it believes are reasonable under the circumstances. The amounts of assets and liabilities reported in the Company's Consolidated Balance Sheets and the amount of expenses reported for each of the periods presented are affected by estimates and assumptions, which are used for, but not limited to, accounting for research and development costs and accounting for share-based compensation. Actual results could differ from those estimates.

Cash and Cash Equivalents and Available-for-Sale Securities

The Company considers all highly liquid investments with an original maturity of 90 days or less when purchased to be cash equivalents. The carrying amounts reported in the Company's Consolidated Balance Sheets for cash and cash equivalents are valued at cost, which approximates their fair value.

The Company considers debt securities with original maturities of greater than 90 days to be available-for-sale securities. Available-for-sale securities with original maturities of greater than one year are recorded as non-current assets. Available-for-sale securities are recorded at fair value and unrealized gains and losses are recorded within other comprehensive income.

On a quarterly basis, the Company reviews the status of each security in an unrealized loss position, to evaluate the existence of potential credit losses. The Company first considers whether it intends to sell, or if it is more likely than not that the Company will be required to sell the security before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the security’s amortized cost basis is written down to fair value through income. For securities that do not meet this criteria, the Company considers a number of factors to determine if the decline in fair value has resulted from credit losses or other factors, including but not limited to: (1) the extent of the decline; (2) changes to the rating of the security by a rating agency; (3) any adverse conditions specific to the security; and (4) other market conditions that may affect the fair value of the security. If this assessment indicates that a credit loss exists and the present value of cash flows expected to be collected is less than the amortized cost basis, an allowance for credit losses is required for the credit loss. Any impairment that has not been recorded through an allowance for credit losses is recognized in other comprehensive income.

As of December 31, 2022, the Company had cash, cash equivalents and available-for-sale securities of approximately $646.8 million. The Company believes that its cash, cash equivalents and available-for-sale securities as of December 31, 2022, will be sufficient to fund its operations and capital expenditure requirements as currently planned for at least the next 12 months from the filing of the Company's Annual Report on Form 10-K.

Concentration of Credit Risk

The Company's financial instruments that are exposed to concentration of credit risk consist primarily of cash, cash equivalents and available-for-sale securities. The Company maintains its cash in bank accounts, the balances of which generally exceed federally insured limits. The Company maintains its cash equivalents and available-for-sale securities in investments in money market funds, in U.S. Treasury securities, U.S. Government Agency securities, investment-grade corporate debt securities, asset-backed securities and debt instruments issued by foreign governments with original maturities of 90 days or less.

The Company believes it is not exposed to significant credit risk on its cash, cash equivalents and available-for-sale securities.

Concentration of Suppliers

The Company historically relied upon a single third-party manufacturer to provide the drug substance for ACP on a purchase order basis. The Company also historically relied upon a single third-party manufacturer to provide fill/finish services for clinical supplies of ACP. The Company has engaged one additional third-party manufacturer to provide drug substance for ACP and one additional third-party manufacturer to provide fill/finish services for clinical supplies of ACP. In addition, the Company currently relies upon a single third-party supplier to supply on a purchase order basis the polyethylene glycol starting material used to manufacture ACP. Furthermore, the Company and its contract manufacturers currently rely upon sole-source suppliers of certain raw materials and other specialized components of production used in the manufacture and fill/finish of ACP. The Company currently relies upon a single third-party contract manufacturer to provide the drug substance for IC-500 for preclinical toxicology studies and early-stage clinical trials and a single third-party contract manufacturer to conduct fill/finish services for IC-500 drug product. If the Company’s third-party manufacturers or fill/finish service providers should become unavailable to the Company for any reason, including as a result of capacity constraints, different business objectives, financial difficulties, insolvency or the impact of COVID-19, the Company believes that there are a limited number of potential replacement manufacturers, and the Company likely would incur added costs and delays in identifying or qualifying such replacements.

Equity Investments

The Company holds investments in equity securities without a readily determinable fair value. Equity investments without a readily determinable fair value are recognized at fair value and are adjusted for observable price changes, or when qualitative assessments indicate that impairment exists, which is recorded in other income (loss).

Financial Instruments

Cash equivalents are reflected in the accompanying financial statements at fair value. The carrying amount of accounts payable and accrued expenses, including accrued research and development expenses, approximates fair value due to the short-term nature of those instruments. The carrying amount of the Company's term loan approximates fair value due to the variable interest rate nature of the debt.

Accounting Standards Codification, or ASC 820, Fair Value Measurements and Disclosures, defines fair value as the price that would be received to sell an asset, or paid to transfer a liability, in the principal or most advantageous market in an orderly transaction between market participants on the measurement date. The fair value standard also establishes a three-level hierarchy, which requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value.

The Company reviews investments on a periodic basis for other than temporary impairments. This review is subjective as it requires management to evaluate whether an event or change in circumstances has occurred in the period that may have a significant adverse effect on the fair value of the investment. The Company uses the market approach to measure fair value for its cash, cash equivalents and available-for-sale financial assets. The market approach uses prices and other relevant information generated by market transactions involving identical or comparable assets. The valuation hierarchy is based upon the transparency of inputs to the valuation of an asset or liability on the measurement date. The three levels are defined as follows:

•Level 1—inputs to the valuation methodology are quoted prices (unadjusted) for an identical asset or liability in an active market. The Company's Level 1 assets consist of investments in money market funds and U.S. Treasury securities.

•Level 2—inputs to the valuation methodology include quoted prices for a similar asset or liability in an active market or model-derived valuations in which all significant inputs are observable for substantially the full term of the asset or liability. The Company's Level 2 assets consist of investments in investment-grade corporate debt securities.

•Level 3—inputs to the valuation methodology are unobservable and significant to the fair value measurement of the asset or liability. The Company does not hold any assets that are measured using Level 3 inputs.

Foreign Currency Translation

The Company considers the U.S. dollar to be its functional currency. Expenses denominated in foreign currencies are translated at the exchange rate on the date the expense is incurred. The effect of exchange rate fluctuations on translating foreign currency assets and liabilities into U.S. dollars is included in the Consolidated Statements of Operations and Comprehensive Loss. Foreign exchange transaction gains and losses are included in the results of operations and are not material in the Company's financial statements.

Income Taxes

The Company utilizes the liability method of accounting for deferred income taxes, as set forth in ASC 740, Income Taxes. Under this method, deferred tax assets and liabilities are recognized for the expected future tax consequences of temporary differences between the carrying amounts and the tax basis of assets and liabilities. A valuation allowance is established against deferred tax assets when, based on the weight of available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. The Company's policy is to record interest and penalties on uncertain tax positions as income tax expense.

Leases

The Company determines if an arrangement contains a lease at inception. For arrangements where the Company is the lessee, it recognizes a right-of-use ("ROU") asset and operating lease liability on the Company's Consolidated Balance Sheet. ROU assets represent the Company's right to use the underlying asset for the lease term and the lease obligation represents the Company's commitment to make the lease payments arising from the lease. Right-of-use lease assets and obligations are recognized at the commencement date based on the present value of remaining lease payments over the lease term. As the Company’s leases do not provide an implicit discount rate, the Company has used an estimated incremental borrowing rate based on the information available at the commencement date in determining the present value of lease payments. ROU assets include any lease payments made prior to commencement and excludes any lease incentives. The lease term may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Operating lease expense is recognized on a straight-line basis over the lease term, subject to any changes in the lease or expectations regarding the terms. Variable lease costs such as common area costs and property taxes are expensed as incurred. For all office lease agreements the Company combines lease and nonlease components. Leases with an initial term of 12 months or less are not recorded on the Company's Consolidated Balance Sheet.

Property and Equipment

Property and equipment, which consists mainly of clinical equipment, laboratory equipment, computers, software, other office equipment, automobiles and leasehold improvements, are carried at cost less accumulated depreciation. Depreciation is computed over the estimated useful lives of the respective assets, generally three to ten years, using the straight-line method. Amortization of leasehold improvements is recorded over the shorter of the lease term or estimated useful life of the related asset.

Research and Development

The Company's research and development expenses primarily consist of costs associated with the manufacturing, development, and preclinical and clinical testing of the Company's product candidates and costs associated with its gene therapy research programs. The Company's research and development expenses consist of:

•external research and development expenses incurred under arrangements with third parties, such as contract research organizations ("CROs") and contract development and manufacturing organizations ("CDMOs") and other vendors for the production and analysis of drug substance and drug product; and

•employee-related expenses for employees dedicated to research and development activities, including salaries, benefits and share-based compensation expense.

Research and development expenses also include costs of acquired product licenses, in-process research and development, and related technology rights where there is no alternative future use, costs of prototypes used in research and development, consultant fees and amounts paid to collaborators.

All research and development expenses are charged to operations as incurred in accordance with ASC 730, Research and Development. The Company accounts for non-refundable advance payments for goods and services that will be used in future research and development activities as expenses when the service has been performed or when the goods have been received, rather than when the payment is made.

Share-Based Compensation

The Company follows the provisions of ASC 718, Compensation—Stock Compensation, which requires the measurement and recognition of compensation expense for all share-based payment awards made to employees, non-employee directors and certain other individuals, including employee stock options, restricted stock units (“RSUs”) and options granted to employees to purchase shares under the 2016 Employee Stock Purchase Plan (the “ESPP”). Share-based compensation expense is based on the grant date fair value estimated in accordance with the provisions of ASC 718 and is generally recognized as an expense over the requisite service period, net of estimated forfeitures. For grants containing performance-based vesting provisions, expense is recognized over the estimated achievement period only when the performance-based milestone is deemed probable of achievement. If performance-based milestones are later determined not to be probable of achievement,

then all previously recorded stock-based compensation expense associated with such options will be reversed during the period in which the Company makes this determination. For grants containing a market condition, the Company estimated the fair value using a Monte Carlo simulation model which takes into consideration different stock price paths. The Company recognizes compensation expense for the market award on a straight-line basis over the derived service period. Compensation expense is recognized for market awards, so long as the requisite service is provided.

The Company estimates forfeitures at the time of grant and revises those estimates in subsequent periods if actual forfeitures differ from its estimates. The Company uses historical data to estimate pre-vesting forfeitures and record share-based compensation expense only for those awards that are expected to vest. To the extent that actual forfeitures differ from the Company's estimates, the difference is recorded as a cumulative adjustment in the period the estimates were revised.

Stock Options

The Company estimates the fair value of stock options granted to employees, non-employees and non-employee directors on the date of grant using the Black-Scholes option-pricing model. The Company's computation of stock-price volatility is based on daily historical volatility during the time period that corresponds to the expected option term. The Company's computation of expected term is determined using the expected term of stock option grants to employees based on an analysis of actual option exercises. The Company utilizes a dividend yield of zero based on the fact that the Company has never paid cash dividends to stockholders and has no current intentions to pay cash dividends. The risk-free interest rate is based on the zero-coupon U.S. Treasury yield at the date of grant for a term equivalent to the expected term of the option.

The weighted-average assumptions used to estimate grant date fair value of stock options using the Black-Scholes option pricing model were as follows for the years ended December 31, 2022, 2021 and 2020:


	Years ended December 31,
	2022	2021	2020
Expected common stock price volatility	84%	114%	118%
Risk-free interest rate	1.38%-4.29%	0.31%-1.22%	0.22%-1.34%
Expected term of options (years)	4.6	5.2	4.6
Expected dividend yield	—	—	—

RSUs

The Company estimates the fair value of RSUs granted to employees using the closing market price of the Company's common stock on the date of grant.

ESPP

In April 2016, the Company's board of directors adopted the ESPP pursuant to which the Company may sell up to an aggregate of 1,000,000 shares of its common stock. The ESPP was approved by the Company’s stockholders in June 2016. The ESPP is considered compensatory and the fair value of the discount and look back provision are estimated using the Black-Scholes option-pricing model and recognized over the six month withholding period prior to purchase.

Share-based compensation expense includes expenses related to stock options and RSUs granted to employees, non-employee directors and consultants, as well as the option granted to employees to purchase shares under the ESPP, all of which have been reported in the Company’s Statements of Operations as follows:


	Years ended December 31,
	2022		2021		2020
Research and development	$	11,865	$	6,522	$	4,166
General and administrative	14,811		4,723		4,157
Total	$	26,676	$	11,245	$	8,323

Recently Adopted Accounting Pronouncements

The Company has evaluated recent accounting pronouncements through the date the financial statements were issued and filed with the SEC and believes that there are none that will have a material impact on the Company’s financial statements.

Income Taxes

12 Months Ended

Dec. 31, 2022

Income Tax Disclosure [Abstract]

Income Taxes

The Company utilizes the liability method of accounting for deferred income taxes. Under this method, deferred tax assets and liabilities are recognized for the expected future tax consequences of temporary differences between the carrying amounts and the tax basis of assets and liabilities. A valuation allowance is established against deferred tax assets when, based on the weight of available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. The Company's policy is to record interest and penalties on uncertain tax positions as income tax expense.

Deferred income taxes reflect the net effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. A reconciliation of the statutory U.S. federal rate to the Company's effective tax rate is as follows:


	Years ended December 31,
	2022		2021		2020
Percent of pre-tax income:
U.S. federal statutory income tax rate	21.0	%	21.0	%	21.0	%
State taxes, net of federal benefit	7.3	%	8.1	%	14.8	%
Permanent items	1.8	%	0.7	%	0.2	%

Impact of state rate changes	—	%	(3.8)	%	0.1	%
Research and development credit	3.7	%	3.3	%	3.1	%

Change in valuation allowance	(33.8)	%	(29.3)	%	(34.8)	%
Effective income tax rate	—	%	—	%	4.4	%

The components of income tax benefit are as follows:


	Years ended December 31,
	2022		2021		2020
Current:
Federal	$	—	$	—	$	—
State	—		—		(3,695)
Deferred:
Federal	—		—		—
State	—		—		—
Income tax benefit	$	—	$	—	$	(3,695)

Significant components of the Company's deferred tax assets (liabilities) for 2022 and 2021 consist of the following:


	As of December 31,
	2022		2021
Deferred tax assets (liabilities)

License and technology payments	$	4,335	$	5,356
Share-based compensation	25,677		21,614
Capitalized R&D	27,527		—
Unrecognized losses from securities	65		—
Accrued expenses	483		320
Right-of-use asset	(335)		(430)
Lease obligation	340		444
Depreciation	(23)		1
Federal and state net operating loss carryforwards	190,163		165,401
Research and development credits	20,931		13,742
Other	35		20
Deferred income tax assets	269,198		206,468
Valuation allowance	(269,198)		(206,468)
Net deferred tax assets	$	—	$	—

The Company considers whether it is more likely than not that some portion or all of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of taxable income during the periods in which the temporary differences representing net future deductible amounts become deductible.

The Company incurred tax losses in 2022 and 2021. The Company has carried forward its federal and state tax losses due to the inability of carryback claims. Federal NOLs incurred prior to 2018 will begin to expire in 2034 if not utilized. Post 2017 Federal NOLs have an unlimited life. The state NOLs are expected to begin to expire in 2025. Due to the Company's history of losses and lack of other positive evidence to support taxable income, the Company has recorded a valuation allowance against those remaining deferred tax assets that are not expected to be realized. In October 2022, the Company was approved to receive approximately $12.5 million through the State of New Jersey's Technology Business Tax Certificate Transfer Program (the "Program") which allows qualified technology and biotechnology businesses in New Jersey to sell unused amounts of NOLs and defined research and development tax credits. As of December 31, 2022, the Company has not received any funds from the Program. As of December 31, 2022, the Company has federal NOL carryforwards of approximately $658.2 million. Pursuant to Internal Revenue Code (“IRC”) Sections 382 and 383, use of the Company’s federal

and state net operating loss and research and development income tax credit carryforwards may be limited in the event of a cumulative change in ownership of more than 50.0% within a three-year period. In October 2021, the Company experienced an ownership change as defined in IRC Section 382. The Company does not anticipate the limitations imposed by IRC Sections 382 and 383 to have a material impact on its ability to utilize net operating losses and credits in future years.

For the years ended December 31, 2022 and 2021, the Company recorded no benefit from income taxes. For the year ended December 31, 2020, the Company recorded an income tax benefit of $3.7 million primarily to reflect the settlements of local tax audits.

On March 27, 2020, in response to the COVID-19 pandemic, the U.S. Congress enacted the Coronavirus Aid, Relief, and Economic Security Act ("CARES Act"). The CARES Act provides numerous tax provisions and other stimulus measures, including the immediate refund of minimum tax credits. In April 2021, the Company received the remaining balance, approximately $1.8 million, of its minimum tax credits refund.

With respect to the remaining deferred tax assets, except for the AMT credits previously discussed above, there was no change in the amount of assets realizable at December 31, 2022.

Pursuant to ASC 740-10, Accounting for Uncertainty in Income Taxes, the Company routinely evaluates the likelihood of success if challenged on income tax positions claimed on its income tax returns. During the year ended December 31, 2022, there was no change in the Company's uncertain tax liability.

The Company's position with respect to uncertain tax positions is set forth below:


Opening balance	$	6,723
Gross amount of increases in unrecognized tax benefits during the period - current year provisions	—
Gross amount of increases in unrecognized tax benefits during the period - prior year provisions	—
Gross amount of decreases in unrecognized tax benefits during the period - other	—
Decreases due to settlement with tax authorities during the period	—
Reduction of unrecognized tax benefits due to expiration of the state of limitations during the period	—
Closing Balance	$	6,723

The Company will continue to evaluate its ability to realize its deferred tax assets on a periodic basis and will adjust such amounts in light of changing facts and circumstances including, but not limited to, future projections of taxable income, tax legislation, rulings by relevant tax authorities, the progress of ongoing tax audits and the regulatory approval of product candidates currently under development. Any additional changes to the valuation allowance recorded on deferred tax assets in the future would impact the Company’s income taxes.

The Company is currently subject to audit by the U.S. Internal Revenue Service, or IRS, for the years 2019 through 2021, and state tax jurisdictions for the years 2018 through 2021. However, the IRS or state tax authorities may still examine and adjust an NOL or R&D credit arising from a closed year to the extent it is utilized in a year that remains subject to audit. The Company’s previously filed income tax returns are not presently under audit by the IRS or state tax authorities.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 21
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32857-109319

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-URI https://asc.fasb.org/extlink&oid=122134291&loc=d3e330215-122817

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 17
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32809-109319

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
-URI https://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 14
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32705-109319

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 270
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6424409&loc=d3e44925-109338

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-URI https://asc.fasb.org/topic&trid=2144680

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=6424122&loc=d3e41874-109331

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

Operating Leases - Schedule of Operating Lease Liability Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Future minimum rental commitments under non-cancelable operating leases
2023	$ 1,216
2024	11
Total minimum lease payments	1,227
Less imputed interest	(27)
Present value of minimum lease payments	1,200
Less current portion	1,189	$ 952
Total long-term operating lease liabilities	$ 11	$ 619

Summary of Significant Accounting Policies - Segment and Geographic Information (Details)	12 Months Ended
	Dec. 31, 2022 segment
Accounting Policies [Abstract]
Number of operating segments	1
Number of reporting segments	1

Summary of Significant Accounting Policies - Property and Equipment (Details)	12 Months Ended
	Dec. 31, 2022
Minimum
Property and equipment
Estimated useful lives	3 years
Maximum
Property and equipment
Estimated useful lives	10 years

Loan and Security Agreement (Tables)

12 Months Ended

Dec. 31, 2022

Debt Disclosure [Abstract]

Schedule of Interest Expense


	Year ended December 31, 2022
Interest expense for 2022 Term Loan Facility	$	2,486
Accretion of end of term charge	215
Amortization of debt issuance costs	251
Total interest expense related to 2022 Term Loan Facility	$	2,952

Schedule of Debt

The principal balance of the 2022 Term Loan Facility and related accretion and amortization as of December 31, 2022, were as follows:


	December 31, 2022
2022 Term Loan Facility, gross (amount drawn)	$	100,000
Debt issuance costs	(3,898)
Accretion of end of term charge	215
Accumulated amortization of debt issuance costs	251
2022 Term Loan Facility, net	$	96,568

Income Taxes - Narrative (Details) - USD ($)	1 Months Ended	12 Months Ended
Income Taxes - Narrative (Details) - USD ($)	Apr. 30, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Oct. 31, 2022
Operating Loss Carryforwards [Line Items]
Income tax benefit		$ 0	$ 0	$ (3,695,000)
Change in unrecognized tax liability		0
The Program
Operating Loss Carryforwards [Line Items]
Income tax receivable					$ 12,500,000
CARES Act
Operating Loss Carryforwards [Line Items]
Proceeds from income tax refunds	$ 1,800,000
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Federal net operating loss carryforwards		$ 658,200,000

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Net Income (Loss) Per Common Share

12 Months Ended

Dec. 31, 2022

Earnings Per Share [Abstract]

Net Income (Loss) Per Common Share

Basic and diluted net loss per common share is determined by dividing net loss by the weighted average common shares and pre-funded warrants outstanding during the period. Basic and diluted shares outstanding includes the weighted average effect of the Company's outstanding pre-funded warrants as the exercise of such pre-funded warrants requires nominal consideration to be given for the delivery of the corresponding shares of common stock. As of December 31, 2022, and 2021, the Company had zero and 3,164,280 pre-funded warrants outstanding, respectively, which if exercised, would increase the number of shares of common stock issued and outstanding. For the periods when there is a net loss, shares underlying stock options and RSUs have been excluded from the calculation of diluted net loss per common share because the effect of including such shares would be anti-dilutive. Therefore, the weighted average common shares used to calculate both basic and diluted net loss per common share would be the same.

The following table sets forth the computation of basic and diluted net income (loss) per common share for the periods indicated:


	Years ended December 31,
	2022		2021		2020
Basic and diluted net income (loss) per common share calculation:
Net loss	$	(185,211)	$	(114,522)	$	(84,547)


Weighted average common shares outstanding - dilutive	121,037		101,866		74,185
Net loss per common share - basic and diluted	$	(1.53)	$	(1.12)	$	(1.14)


	Years ended December 31,
	2022	2021	2020
Stock options outstanding	12,402,629	10,861,483	8,927,698
Restricted stock units	3,025,941	2,246,269	1,958,383
Total	15,428,570	13,107,752	10,886,081

Consolidated Statements of Changes in Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Underwritten Offering	Junior Series A Preferred Stock	Common Stock	Common Stock Underwritten Offering	Additional paid-in capital	Additional paid-in capital Underwritten Offering	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)
Balance at beginning of period (in shares) at Dec. 31, 2019			0	49,627
Balance at beginning of period at Dec. 31, 2019	$ 117,203		$ 0	$ 50		$ 597,679		$ (480,526)	$ 0
Increase (Decrease) in Stockholders' Equity
Issuance of common stock and pre-funded warrants, net (in shares)				28,504
Issuance of common stock and pre-funded warrants, net	116,883			$ 28		116,855
Issuance of common stock in connection with license acquisition (in shares)				8,649
Issuance of common stock in connection with private offering	33,237			$ 9		33,228
Issuance of common stock under employee stock compensation plan (in shares)				841
Issuance of common stock under employee stock compensation plans	461			$ 1		460
Share-based compensation	8,323					8,323
Issuance of common stock under the exercise of pre-funded warrants (in shares)				2,500
Issuance of common stock under the exercise of pre-funded warrants	0			$ 2		(2)
Net loss	(84,547)							(84,547)
Unrealized gain on available for sale securities, net of tax	3								3
Balance at end of period (in shares) at Dec. 31, 2020			0	90,121
Balance at beginning of period at Dec. 31, 2020	191,563		$ 0	$ 90		756,543		(565,073)	3
Increase (Decrease) in Stockholders' Equity
Issuance of common stock and pre-funded warrants, net (in shares)					23,748
Issuance of common stock and pre-funded warrants, net		$ 270,319			$ 24		$ 270,295
Issuance of common stock under employee stock compensation plan (in shares)				1,408
Issuance of common stock under employee stock compensation plans	2,016			$ 1		2,015
Share-based compensation	11,245					11,245
Net loss	(114,522)							(114,522)
Unrealized gain on available for sale securities, net of tax	(93)								(93)
Balance at end of period (in shares) at Dec. 31, 2021			0	115,277
Balance at beginning of period at Dec. 31, 2021	360,528		$ 0	$ 115		1,040,098		(679,595)	(90)
Increase (Decrease) in Stockholders' Equity
Issuance of common stock and pre-funded warrants, net (in shares)					15,353
Issuance of common stock and pre-funded warrants, net		$ 324,290			$ 15		$ 324,275
Issuance of common stock under employee stock compensation plan (in shares)				6,010
Issuance of common stock under employee stock compensation plans	8,513			$ 7		8,506
Share-based compensation	26,676					26,676
Net loss	(185,211)							(185,211)
Unrealized gain on available for sale securities, net of tax	(139)								(139)
Balance at end of period (in shares) at Dec. 31, 2022			0	136,640
Balance at beginning of period at Dec. 31, 2022	$ 534,657		$ 0	$ 137		$ 1,399,555		$ (864,806)	$ (229)

Summary of Significant Accounting Policies - Schedule of Weighted-Average Assumptions (Details)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield	0.00%
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected common stock price volatility	84.00%	114.00%	118.00%
Risk-free interest rate, minimum	1.38%	0.31%	0.22%
Risk-free interest rate, maximum	4.29%	1.22%	1.34%
Expected term of options (years)	4 years 7 months 6 days	5 years 2 months 12 days	4 years 7 months 6 days
Expected dividend yield	0.00%	0.00%	0.00%

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Current assets
Cash and cash equivalents	$ 476,304	$ 261,447
Available for sale securities	170,531	120,302
Prepaid expenses and other current assets	15,991	5,739
Total current assets	662,826	387,488
Property and equipment, net	946	348
Right-of-use assets, net	1,182	1,522
Other assets	1,869	0
Total assets	666,823	389,358
Current liabilities
Accrued research and development expenses	11,555	14,403
Accounts payable and accrued expenses	22,843	12,856
Lease liability, current	1,189	952
Total current liabilities	35,587	28,211
Lease liability, non-current	11	619
Debt, non-current	96,568	0
Total liabilities	132,166	28,830
Stockholders' equity
Preferred stock—$0.001 par value, 5,000,000 shares authorized, no shares issued or outstanding	0	0
Common stock—0.001 par value, 200,000,000 shares authorized, 136,639,687 and 115,277,012 shares issued and outstanding at December 31, 2022 and December 31, 2021, respectively	137	115
Additional paid-in capital	1,399,555	1,040,098
Accumulated deficit	(864,806)	(679,595)
Accumulated other comprehensive income	(229)	(90)
Total stockholders' equity	534,657	360,528
Total liabilities and stockholders' equity	$ 666,823	$ 389,358

Employee Benefit Plan	12 Months Ended
Employee Benefit Plan	Dec. 31, 2022
Retirement Benefits [Abstract]
Employee Benefit Plan	Employee Benefit PlanThe Company maintains a defined contribution 401(k) plan available to employees. Employee contributions are voluntary and are determined on an individual basis, limited by the maximum amounts allowable under federal tax regulations. The Company's matching contributions to employees totaled approximately $1.0 million, $0.6 million and $0.3 million during the years ended December 31, 2022, 2021, and 2020, respectively.

- Definition

The entire disclosure for retirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI https://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
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-URI https://asc.fasb.org/extlink&oid=21916913&loc=d3e273930-122802

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Net Income (Loss) Per Common Share - Schedule of Basic and Diluted Net Income (Loss) Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Basic and diluted net income (loss) per common share calculation:
Net loss	$ (185,211)	$ (114,522)	$ (84,547)
Weighted average common shares outstanding - dilutive (in shares)	121,037	101,866	74,185
Net loss per common share - basic (in dollars per share)	$ (1.53)	$ (1.12)	$ (1.14)
Net loss per common share - diluted (in dollars per share)	$ (1.53)	$ (1.12)	$ (1.14)

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Business	12 Months Ended
Business	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business	Business Description of Business and Organization IVERIC bio, Inc. (the “Company”) is a science-driven biopharmaceutical company focused on the discovery and development of novel treatments for retinal diseases with significant unmet medical needs. The Company is committed to having a positive impact on patients’ lives by delivering high-quality, safe and effective treatments designed to address debilitating retinal diseases, including earlier stages of age-related macular degeneration (“AMD”). The Company’s lead asset is its clinical stage product candidate avacincaptad pegol (also referred to as ACP or Zimura), a complement C5 inhibitor. It is currently targeting the following diseases with ACP: •Geographic Atrophy (“GA”), which is the advanced stage of AMD, and is characterized by marked thinning or atrophy of retinal tissue, leading to irreversible loss of vision; •intermediate AMD, which is an earlier stage of AMD; and •autosomal recessive Stargardt disease (“STGD1”), which is an orphan inherited condition characterized by progressive damage to the central portion of the retina (the “macula”) and other retinal tissue, leading to loss of vision. In October 2019, the Company announced positive 12-month data for GATHER1, its first Phase 3 clinical trial evaluating ACP for the treatment of GA secondary to AMD. In GATHER1, 286 patients were randomized to receive various doses of ACP, including ACP 2 mg, or sham control. The Company observed a 27.7% (p-value = 0.0063) reduction in the mean rate of growth (slope) estimated based on GA area between the ACP 2 mg group and the corresponding sham control group over 12 months, when performing the primary analysis, and a 35.4% (p-value = 0.0050) reduction in the mean rate of growth (slope) estimated based on GA area between the two groups over 12 months, when performing the supportive analysis. These results are based on a post-hoc analysis of the GATHER1 data using the U.S. Food and Drug Administration (“FDA”) preferred primary efficacy endpoint analysis from the Company’s Special Protocol Assessment (“SPA”), which is described further below. The Company analyzed the endpoint by using the square root transformation of the GA area, which it refers to as the primary analysis, and the Company analyzed the endpoint by using the observed GA area (without square root transformation), which it refers to as the supportive analysis. In GATHER1, through month 12, the Company did not observe any events of endophthalmitis or ischemic optic neuropathy events, and only one case of intraocular inflammation, which was mild and transient and reported as related to the injection procedure. The incidence of choroidal neovascularization (“CNV”) in the study eye through month 12 was 6 patients (9.0%) in the ACP 2 mg group and 3 patients (2.7%) in the corresponding sham control group. In June 2020, the Company started enrolling patients in GATHER2, its second Phase 3 clinical trial evaluating ACP for the treatment of GA secondary to AMD. In July 2021, the Company received a written agreement from the FDA under the SPA for the overall design of GATHER2. The SPA is a procedure by which the FDA provides a clinical trial sponsor with an official evaluation and written guidance on the design of a proposed protocol intended to form the basis for a new drug application (“NDA”). In connection with our SPA, the FDA recommended, and the Company accepted, modifying the primary efficacy endpoint for the GATHER2 trial from the mean rate of change in GA area over 12 months measured by fundus autofluorescence (“FAF”) at three timepoints: baseline, month 6 and month 12, to the mean rate of growth (slope) estimated based on GA area measured by FAF in at least three timepoints: baseline, month 6 and month 12. In September 2022, the Company announced positive 12-month top-line data for GATHER2. In GATHER2, 448 patients were randomized on a 1:1 basis to receive ACP 2 mg or sham control over the first 12 months of the trial. At 12 months, the Company measured the primary efficacy endpoint in accordance with the SPA. In GATHER2, the Company observed a 14.3% (p-value = 0.0064) reduction in the mean rate of growth (slope) in GA area between the two groups at 12 months with the primary analysis, and a 17.7% (p-value = 0.0039) reduction in the mean rate of growth (slope) in GA area between the two groups at 12 months with the supportive analysis. The Company did not observe any events of endophthalmitis, intraocular inflammation events, events of vasculitis or ischemic optic neuropathy events through month 12, and the incidence of choroidal neovascularization (“CNV”) in the study eye through month 12 was 15 patients (6.7%) in the ACP 2 mg group and 9 patients (4.1%) in the sham control group. The Company believes that with the statistically significant results from its GATHER1 and GATHER2 trials and the safety profile of ACP to date, it has sufficient data from two independent, adequate and well-controlled pivotal clinical trials of ACP in GA secondary to AMD to support an application for marketing approval. In November 2022, ACP became the first investigational drug product to receive breakthrough therapy designation from the FDA for the treatment of GA secondary to AMD. In December 2022, the Company completed the rolling submission of its new drug application ("NDA") to the FDA for marketing approval of ACP for the treatment of GA secondary to AMD. In February 2023, the FDA accepted its NDA for filing and granted priority review with a Prescription Drug User Fee Act ("PDUFA") target action date of August 19, 2023. In addition to ACP, the Company is developing its preclinical product candidate IC-500, a High temperature requirement A serine peptidase 1 protein (“HtrA1”) inhibitor, for GA secondary to AMD and potentially other age-related retinal diseases. Based on current timelines and subject to successful preclinical development and current good manufacturing practices manufacturing, the Company expects to submit an investigational new drug application to the FDA for IC-500 during the first half of 2024. The Company’s portfolio also includes several ongoing gene therapy research programs, each of which uses adeno-associated virus (“AAV”) for gene delivery. These AAV mediated gene therapy programs are targeting the following orphan inherited retinal diseases (“IRDs”): •Leber Congenital Amaurosis type 10 (“LCA10”), which is characterized by severe bilateral loss of vision at or soon after birth; •STGD1; and •IRDs associated with mutations in the USH2A gene, which include Usher syndrome type 2A, and USH2A-associated non-syndromic autosomal recessive retinitis pigmentosa.

Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Percent of pre-tax income:
U.S. federal statutory income tax rate	21.00%	21.00%	21.00%
State taxes, net of federal benefit	7.30%	8.10%	14.80%
Permanent items	1.80%	0.70%	0.20%
Impact of state rate changes	0.00%	(3.80%)	0.10%
Research and development credit	3.70%	3.30%	3.10%
Change in valuation allowance	(33.80%)	(29.30%)	(34.80%)
Effective income tax rate	0.00%	0.00%	4.40%

Cover - USD ($) $ in Millions	12 Months Ended
Cover - USD ($) $ in Millions	Dec. 31, 2022	Feb. 27, 2023	Jun. 30, 2022
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2022
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-36080
Entity Registrant Name	IVERIC bio, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	20-8185347
Entity Address, Address Line One	8 Sylvan Way
Entity Address, City or Town	Parsippany
Entity Address, State or Province	NJ
Entity Address, Postal Zip Code	07054
City Area Code	609
Local Phone Number	474-6455
Title of 12(b) Security	Common Stock, $0.001 par value
Trading Symbol	ISEE
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 1,093.4
Entity Common Stock, Shares Outstanding (in shares)		137,122,338
Documents Incorporated by Reference	Part III of this Annual Report incorporates by reference information from the definitive Proxy Statement for the registrant's 2023 Annual Meeting of Shareholders, which is expected to be filed with the Securities and Exchange Commission not later than 120 days after the registrant's fiscal year ended December 31, 2022.
Entity Central Index Key	0001410939
Amendment Flag	false
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	FY

Loan and Security Agreement - Narrative (Details) - 2022 Term Loan	Jul. 26, 2022 USD ($)
Debt Instrument [Line Items]
Lenders option to invest in equity financing	$ 10,000,000
Net cash proceeds	75,000,000
Line of Credit
Debt Instrument [Line Items]
Aggregate principal amount (up to)	$ 250,000,000
Capped interest rate per annum	10.25%
Interest-only payment, period	42 months
Covenant revenue from sale, maintained market capitalization	$ 600,000,000
End term charges percentage	4.25%
Prepayment penalty prior first year	2.00%
Prepayment penalty second year	1.50%
Prepayment penalty thereafter	0.75%
Line of Credit \| Minimum
Debt Instrument [Line Items]
Qualified cash percent	50.00%
Line of Credit \| Maximum
Debt Instrument [Line Items]
Qualified cash percent	90.00%
Line of Credit \| The Wall Street Journal prime rate
Debt Instrument [Line Items]
Basis spread on variable rate	6.25%
Line of Credit \| The Wall Street Journal prime rate \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	4.00%
Line of Credit \| The Wall Street Journal prime rate \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	8.75%
Line of Credit \| On Closing Date
Debt Instrument [Line Items]
Aggregate principal amount (up to)	$ 50,000,000
Line of Credit \| Milestone 1 is achieved through December 15, 2022
Debt Instrument [Line Items]
Aggregate principal amount (up to)	50,000,000
Drawn down increments at company's election	5,000,000
Line of Credit \| Milestone 2 is achieved through September 30, 2023
Debt Instrument [Line Items]
Aggregate principal amount (up to)	25,000,000
Drawn down increments at company's election	5,000,000
Line of Credit \| Milestone 3 is achieved
Debt Instrument [Line Items]
Aggregate principal amount (up to)	75,000,000
Drawn down increments at company's election	5,000,000
Line of Credit \| Subject to FDA approval of Zimura in GA
Debt Instrument [Line Items]
Aggregate principal amount (up to)	50,000,000
Drawn down increments at company's election	5,000,000
Convertible Notes
Debt Instrument [Line Items]
Aggregate principal amount (up to)	$ 400,000,000
Convertible Notes \| Minimum
Debt Instrument [Line Items]
Maturity date no earlier than	6 months
Revolving Credit Facility \| Milestone 3 is achieved
Debt Instrument [Line Items]
Aggregate principal amount (up to)	$ 50,000,000

Consolidated Statements of Operations - USD ($) shares in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Operating expenses:
Research and development	$ 117,012,000	$ 85,068,000	$ 62,784,000
General and administrative	72,894,000	29,689,000	25,952,000
Total operating expenses	189,906,000	114,757,000	88,736,000
Loss from operations	(189,906,000)	(114,757,000)	(88,736,000)
Interest income, net	2,264,000	245,000	500,000
Gain on sale of IC100 & IC200	2,369,000	0	0
Other income (expense), net	62,000	(10,000)	(6,000)
Loss before income tax benefit	(185,211,000)	(114,522,000)	(88,242,000)
Income tax benefit	0	0	3,695,000
Net loss	$ (185,211,000)	$ (114,522,000)	$ (84,547,000)
Net loss per common share:
Basic (in dollars per share)	$ (1.53)	$ (1.12)	$ (1.14)
Diluted (in dollars per share)	$ (1.53)	$ (1.12)	$ (1.14)
Weighted average common shares outstanding:
Basic (in shares)	121,037	101,866	74,185
Diluted (in shares)	121,037	101,866	74,185

Cash, Cash Equivalents and Available-for-Sale Securities - Schedule of Available for Sale Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 170,760	$ 120,392
Gross Unrealized Gains	28	0
Gross Unrealized Losses	(257)	(90)
Fair Value	170,531	120,302
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	27,481	18,202
Gross Unrealized Gains	3	0
Gross Unrealized Losses	(61)	(16)
Fair Value	27,423	18,185
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	109,248	82,138
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(119)	(57)
Fair Value	109,129	82,081
U.S. government agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	9,644
Gross Unrealized Gains	25
Gross Unrealized Losses	0
Fair Value	9,669
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	19,360	16,008
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(63)	(14)
Fair Value	19,297	15,995
Supranational securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	5,027	4,044
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(14)	(3)
Fair Value	$ 5,013	$ 4,041

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2022

Accounting Policies [Abstract]

Schedule of Weighted-average Assumptions Used to Estimate Grant Date Fair Value of Stock Options


	Years ended December 31,
	2022	2021	2020
Expected common stock price volatility	84%	114%	118%
Risk-free interest rate	1.38%-4.29%	0.31%-1.22%	0.22%-1.34%
Expected term of options (years)	4.6	5.2	4.6
Expected dividend yield	—	—	—

Schedule of Share-based Compensation Expense


	Years ended December 31,
	2022		2021		2020
Research and development	$	11,865	$	6,522	$	4,166
General and administrative	14,811		4,723		4,157
Total	$	26,676	$	11,245	$	8,323

Income Taxes - Schedule of Position with Respect to Uncertain Tax Positions (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($)
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Opening balance	$ 6,723
Gross amount of increases in unrecognized tax benefits during the period - current year provisions	0
Gross amount of increases in unrecognized tax benefits during the period - prior year provisions	0
Gross amount of decreases in unrecognized tax benefits during the period - other	0
Decreases due to settlement with tax authorities during the period	0
Reduction of unrecognized tax benefits due to expiration of the state of limitations during the period	0
Closing Balance	$ 6,723

Stock-Based Compensation and Compensation Plans - Summary of Outstanding RSU Awards Granted (Details) - Restricted stock units shares in Thousands	12 Months Ended
	Dec. 31, 2022 $ / shares shares
Restricted Stock Units
Outstanding, beginning of period (in shares) \| shares	2,246
Awarded (in shares) \| shares	1,565
Vested (in shares) \| shares	(739)
Expired or forfeited (in shares) \| shares	(46)
Outstanding, end of period (in shares) \| shares	3,026
Weighted Average Grant-Date Fair Value
Outstanding, beginning of period (in dollars per share) \| $ / shares	$ 9.82
Awarded (in dollars per share) \| $ / shares	19.15
Vested (in dollars per share) \| $ / shares	7.81
Expired or forfeited (in dollars per share) \| $ / shares	10.96
Outstanding, end of period (in dollars per share) \| $ / shares	$ 15.12

Operating Leases - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Leases [Abstract]
Operating lease rent expense	$ 1.4	$ 0.7	$ 0.6
Cash paid from operating cash flows	$ 1.4	$ 0.7
Operating lease, weighted average remaining lease term	8 months 12 days
Weighted average estimated incremental borrowing rate	5.60%

Commitments and Contingencies - miniCEP290 Program - University of Massachusetts (Details) - University Of Massachusetts (UMass) - miniCEP290 - License Agreements - USD ($)	1 Months Ended		12 Months Ended
	Sep. 30, 2019	Jul. 31, 2019	Dec. 31, 2022
Schedule of Commitments and Contingencies [Line Items]
Shares issued for license fees (in shares)		75,000
Research and development
Schedule of Commitments and Contingencies [Line Items]
Payments for license fees	$ 400,000
Achievement of Specified Clinical and Regulatory Milestones \| Research and development
Schedule of Commitments and Contingencies [Line Items]
Payments for license fees		$ 14,750,000	$ 14,750,000
Shares issued for license fees (in shares)		75,000	75,000
Specified Commercial Sales Milestones Related to a Licensed Product \| Research and development
Schedule of Commitments and Contingencies [Line Items]
Payments for license fees		$ 48,000,000	$ 48,000,000

Loan and Security Agreement - Term Loan And Related Accretion And Amortization (Details) - 2022 Term Loan $ in Thousands	Dec. 31, 2022 USD ($)
Debt Instrument [Line Items]
2022 Term Loan Facility, gross (amount drawn)	$ 100,000
Debt issuance costs	(3,898)
Accretion of end of term charge	215
Accumulated amortization of debt issuance costs	251
2022 Term Loan Facility, net	$ 96,568

- Definition

Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References + Details

Cash, Cash Equivalents and Available-for-Sale Securities - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Cash and Cash Equivalents [Abstract]
Cash and cash equivalents	$ 476,304	$ 261,447
Cash	600	9,900
Cash equivalents	475,700	251,500
Available for sale debt securities	$ 170,531	$ 120,302

Summary of Significant Accounting Policies - Cash and Cash Equivalents (Details) $ in Millions	Dec. 31, 2022 USD ($)
Accounting Policies [Abstract]
Cash, cash equivalents and available for sale securities	$ 646.8

Fair Value Measurements

12 Months Ended

Dec. 31, 2022

Fair Value Disclosures [Abstract]

Fair Value Measurements

The Company classifies its available-for-sale securities within the fair value hierarchy as Level 2 assets, as it primarily utilizes quoted market prices or rates for similar instruments to value these securities.

In December 2022, IVERIC bio Gene Therapy LL ("Iveric Subsidiary"), the Company's wholly owned subsidiary, entered into an Asset Purchase Agreement (the "Purchase Agreement") with Opus Genetics Inc. ("Opus"), a privately held company, pursuant to which Opus acquired all rights, title and interests in and to Iveric Subsidiary's assets primarily related to the Company's IC-100 and IC-200 product candidates, including the Company's exclusive license agreements with the University of Florida Research Foundation, Incorporated, and the Trustees of the University of Pennsylvania for both product candidates and certain related sponsored research agreements . Under the terms of the Purchase Agreement, the Iveric Subsidiary received (i) an upfront cash payment in the amount of $500,000 and (ii) 2,632,720 shares of Series Seed Preferred Stock of Opus (the "Opus shares"), par value $0.00001 per share, pursuant to a Stock Issuance Agreement (the "Opus SPA") that the parties entered into concurrently with the Purchase Agreement, resulting in the Iveric Subsidiary owning of a high single-digit percentage of the outstanding capital stock of Opus on a fully diluted basis. The Purchase Agreement and the Opus SPA provide for Opus to issue additional shares of capital stock that will maintain Iveric Subsidiary’s ownership at a mid to high single-digit percentage of the fully diluted outstanding capital stock of Opus through Opus’s next round of financing in which it raises a specified minimum amount of gross proceeds. Iveric Subsidiary is also eligible to receive (i) contingent development and regulatory milestone payments of up to $12.8 million and (ii) additional sales milestone payments of up to $98.9 million from Opus. Further, the Iveric Subsidiary will receive, on a country-by-country and product-by-product basis, an earn-out of a low single-digit percentage on net sales of IC-100 and IC-200. The fair value of the contingent consideration was determined to be de minimus.

In connection with the Purchase Agreement, the Company recognized the Opus shares at a fair value of $1.9 million using an option pricing valuation model that included assumptions for the volatility of Opus common stock (based on the historical volatility of similar companies), weighted time to exit, and market adjustments (Level 3 inputs). The Opus shares are presented within "other assets" in the accompanying Consolidated Balance Sheets.

The following table presents, for each of the fair value hierarchy levels required under ASC 820, the Company's assets and liabilities that are measured at fair value on a recurring basis as of December 31, 2022:


	Fair Value Measurement Using
	Quoted prices in active markets for identical assets (Level 1)		Significant other observable inputs (Level 2)		Significant unobservable inputs (Level 3)
Assets
Investments in money market funds*	$	475,689	$	—	$	—

Investments in U.S. Treasury securities	$	27,423	$	—	$	—
Investments in corporate debt securities	$	—	$	109,129	$	—
Investments in U.S. government agency securities	—		$	9,669	—
Investments in asset-backed securities	$	—	$	19,297	$	—
Investments in supranational securities	$	—	$	5,013	$	—


	Fair Value Measurement Using
	Quoted prices in active markets for identical assets (Level 1)		Significant other observable inputs (Level 2)		Significant unobservable inputs (Level 3)
Assets
Investments in money market funds*	$	251,488	$	—	$	—
Investments in U.S. Treasury securities	$	18,185	$	—	$	—
Investments in corporate debt securities	$	—	$	82,081	$	—
Investments in asset-backed securities	$	—	$	15,995	$	—
Investments in supranational securities	—		4,041		—

*Investments in money market funds are reflected in cash and cash equivalents in the accompanying Consolidated Balance Sheets.

No transfer of assets between Level 1 and Level 2 of the fair value measurement hierarchy occurred during the years ended December 31, 2022 or December 31, 2021.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Commitments and Contingencies - Avacincaptad Pegol - Archemix Corp. (Details)		1 Months Ended			8 Months Ended	12 Months Ended
	Jun. 30, 2022 EUR (€)	Oct. 31, 2020 USD ($)	Mar. 31, 2020 USD ($)	Sep. 30, 2011 USD ($)	Oct. 31, 2020 USD ($)	Dec. 31, 2022 EUR (€)	Dec. 31, 2022 USD ($)
DelSiTech \| Avacincaptad Pegol \| License Agreements
Schedule of Commitments and Contingencies [Line Items]
Payments for license fees \| €	€ 1,250,000
Achievement of Specified Clinical and Regulatory Milestones \| Archemix \| C5 Licensed Product \| License Agreements
Schedule of Commitments and Contingencies [Line Items]
Amount to be paid on achievement of milestone							$ 50,500,000
Payments for license fees		$ 6,000,000	$ 1,000,000	$ 1,000,000	$ 9,000,000
Achievement of Specified Clinical and Regulatory Milestones \| Archemix \| C5 Licensed Product \| Maximum \| License Agreements
Schedule of Commitments and Contingencies [Line Items]
Amount to be paid on achievement of milestone				50,500,000
First Indication \| Archemix \| C5 Licensed Product \| License Agreements
Schedule of Commitments and Contingencies [Line Items]
Amount to be paid on achievement of milestone				24,500,000			24,500,000
Second and Third Indication \| Archemix \| C5 Licensed Product \| License Agreements
Schedule of Commitments and Contingencies [Line Items]
Amount to be paid on achievement of milestone				23,500,000			23,500,000
Sustained Delivery Applications \| Archemix \| C5 Licensed Product \| License Agreements
Schedule of Commitments and Contingencies [Line Items]
Amount to be paid on achievement of milestone				2,500,000			2,500,000
Achievement of Specified Commercial Milestones \| Archemix \| C5 Licensed Product \| License Agreements
Schedule of Commitments and Contingencies [Line Items]
Amount to be paid on achievement of milestone							$ 22,500,000
Achievement of Specified Commercial Milestones \| Archemix \| C5 Licensed Product \| Maximum \| License Agreements
Schedule of Commitments and Contingencies [Line Items]
Amount to be paid on achievement of milestone				$ 22,500,000
Achievement Of Specified Clinical And Development Milestones \| DelSiTech \| Avacincaptad Pegol \| License Agreements
Schedule of Commitments and Contingencies [Line Items]
Amount to be paid on achievement of milestone \| €	35,000,000
Achievement Of Specified Commercial Sales Milestones \| DelSiTech \| Avacincaptad Pegol \| License Agreements
Schedule of Commitments and Contingencies [Line Items]
Payments for license fees \| €	€ 60,000,000					€ 60,000,000

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2022

Income Tax Disclosure [Abstract]

Schedule of Reconciliation of the Statutory U.S. Federal Rate to the Company's Effective Tax Rate

A reconciliation of the statutory U.S. federal rate to the Company's effective tax rate is as follows:


	Years ended December 31,
	2022		2021		2020
Percent of pre-tax income:
U.S. federal statutory income tax rate	21.0	%	21.0	%	21.0	%
State taxes, net of federal benefit	7.3	%	8.1	%	14.8	%
Permanent items	1.8	%	0.7	%	0.2	%

Impact of state rate changes	—	%	(3.8)	%	0.1	%
Research and development credit	3.7	%	3.3	%	3.1	%

Change in valuation allowance	(33.8)	%	(29.3)	%	(34.8)	%
Effective income tax rate	—	%	—	%	4.4	%

Schedule of Components of Income Tax Benefit

The components of income tax benefit are as follows:


	Years ended December 31,
	2022		2021		2020
Current:
Federal	$	—	$	—	$	—
State	—		—		(3,695)
Deferred:
Federal	—		—		—
State	—		—		—
Income tax benefit	$	—	$	—	$	(3,695)

Schedule of Significant Components of the Company's Deferred Tax Assets (Liabilities)

Significant components of the Company's deferred tax assets (liabilities) for 2022 and 2021 consist of the following:


	As of December 31,
	2022		2021
Deferred tax assets (liabilities)

License and technology payments	$	4,335	$	5,356
Share-based compensation	25,677		21,614
Capitalized R&D	27,527		—
Unrecognized losses from securities	65		—
Accrued expenses	483		320
Right-of-use asset	(335)		(430)
Lease obligation	340		444
Depreciation	(23)		1
Federal and state net operating loss carryforwards	190,163		165,401
Research and development credits	20,931		13,742
Other	35		20
Deferred income tax assets	269,198		206,468
Valuation allowance	(269,198)		(206,468)
Net deferred tax assets	$	—	$	—

Schedule of Position With Respect to Uncertain Tax Positions

The Company's position with respect to uncertain tax positions is set forth below:


Opening balance	$	6,723
Gross amount of increases in unrecognized tax benefits during the period - current year provisions	—
Gross amount of increases in unrecognized tax benefits during the period - prior year provisions	—
Gross amount of decreases in unrecognized tax benefits during the period - other	—
Decreases due to settlement with tax authorities during the period	—
Reduction of unrecognized tax benefits due to expiration of the state of limitations during the period	—
Closing Balance	$	6,723

Common Stock - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended				12 Months Ended
	Dec. 31, 2022	Oct. 31, 2021	Jul. 31, 2021	Jun. 30, 2020	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Jul. 30, 2021
Class of Stock [Line Items]
Underwriting discounts and commissions	$ 21,100	$ 10,800	$ 7,400	$ 10,100
Net proceeds	$ 324,300	$ 162,600		$ 150,100
Number of warrants issued (in shares)				1,914,280
Public Stock Offering
Class of Stock [Line Items]
Shares issued (in shares)	15,352,500	10,350,000	13,397,500
Stock price (in dollars per share)	$ 22.50	$ 16.75			$ 22.50			$ 8.60
Net proceeds			$ 107,800		$ 324,290	$ 270,319	$ 116,883
Over-Allotment Option
Class of Stock [Line Items]
Shares issued (in shares)	2,002,500	1,350,000	1,747,500
Stock price (in dollars per share)	$ 21.15	$ 15.745			$ 21.15			$ 8.084
Underwritten Offering
Class of Stock [Line Items]
Shares issued (in shares)				28,503,220
Stock price (in dollars per share)				$ 4.10
Underwritten Offering, Underwriters
Class of Stock [Line Items]
Stock price (in dollars per share)				$ 3.854
Private Placement
Class of Stock [Line Items]
Shares issued (in shares)				8,649,453
Stock price (in dollars per share)				$ 4.10
Net proceeds					$ 0	$ 0	$ 33,237
Warrant price (in dollars per share)				4.099
Private Placement, Underwriters
Class of Stock [Line Items]
Warrant price (in dollars per share)				$ 3.853

Income Taxes - Schedule of Significant Components of Deferred Tax Assets (Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Deferred tax assets (liabilities)
License and technology payments	$ 4,335	$ 5,356
Share-based compensation	25,677	21,614
Capitalized R&D	27,527	0
Unrecognized losses from securities	65	0
Accrued expenses	483	320
Right-of-use asset	(335)	(430)
Lease obligation	340	444
Depreciation		1
Depreciation	(23)
Federal and state net operating loss carryforwards	190,163	165,401
Research and development credits	20,931	13,742
Other	35	20
Deferred income tax assets	269,198	206,468
Valuation allowance	(269,198)	(206,468)
Net deferred tax assets	$ 0	$ 0

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Operating Activities
Net loss	$ (185,211)	$ (114,522)	$ (84,547)
Adjustments to reconcile net loss to net cash (used in) provided by operating activities:
Depreciation	138	39	143
Amortization of debt issuance costs	466	0	0
Amortization of premium and discounts on investment securities	(623)	1,182	462
Proceeds from sale of IC100 & IC 200	(500)	0	0
Share-based compensation	26,676	11,245	8,323
Change in working capital	(31)	54	0
Changes in operating assets and liabilities:
Income tax receivable	0	1,765	0
Prepaid expense and other assets	(12,121)	(943)	(2,742)
Accrued interest receivable	296	438	(323)
Accrued research and development expenses	(2,848)	2,119	5,424
Accounts payable and accrued expenses	9,987	64	7,163
Net cash used in operating activities	(163,771)	(98,559)	(66,097)
Investing Activities
Purchase of marketable securities	(231,040)	(142,821)	(143,810)
Maturities of marketable securities	180,999	164,480	0
Purchase of property and equipment	(736)	(361)	0
Proceeds from sale of assets	500	0	0
Net cash provided by (used in) investing activities	(50,277)	21,298	(143,810)
Financing Activities
Proceeds from employee stock plan purchases and stock option exercises	8,513	2,016	461
Proceeds from term loan	100,000	0	0
Payment of term loan issuance costs	(3,898)	0	0
Net cash provided by financing activities	428,905	272,335	150,581
Net increase (decrease) in cash and cash equivalents	214,857	195,074	(59,326)
Cash and cash equivalents
Beginning of period	261,447	66,373	125,699
End of period	476,304	261,447	66,373
Supplemental disclosure of cash paid
Interest expense paid in cash	1,760	0	0
Income taxes received, net	0	(1,765)	(3,327)
Supplemental disclosures of non-cash information related to investing activities
Change in unrealized gain (loss) on available for sale securities, net of tax	(139)	(93)	3
Operating right-of-use assets obtained in exchange for lease obligations	953	2,086	166
Preferred stock received for the sale of IC100 & IC200	1,869	0	0
Public Stock Offering
Financing Activities
Proceeds from issuance of common stock	324,290	270,319	116,883
Private Placement
Financing Activities
Proceeds from issuance of common stock	$ 0	$ 0	$ 33,237

Employee Benefit Plan (Details) - USD ($) $ in Millions	12 Months Ended
Employee Benefit Plan (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Retirement Benefits [Abstract]
Defined contribution plan, cost recognized	$ 1.0	$ 0.6	$ 0.3

Property and Equipment (Tables)

12 Months Ended

Dec. 31, 2022

Property, Plant and Equipment [Abstract]

Schedule of Property and Equipment

Property and equipment as of December 31, 2022 and 2021 were as follows:


	Useful Life (Years)	December 31, 2022		December 31, 2021
Research, manufacturing and clinical equipment	5 - 10	$	548	$	283
Computer, software and other office equipment	5	1,201		933
Furniture and fixtures	7	203		—
Automobile	5	125		125
		2,077		1,341
Accumulated depreciation		(1,131)		(993)
Property and equipment, net		$	946	$	348

Licensing and Commercialization Agreements - License Agreement with University of Massachusetts for the miniCEP290 Program (Details)		1 Months Ended		12 Months Ended
	Jun. 30, 2022 EUR (€)	Sep. 30, 2019 USD ($)	Jul. 31, 2019 USD ($) shares	Dec. 31, 2022 USD ($) shares	Dec. 31, 2022 EUR (€) shares
University Of Massachusetts (UMass) \| miniCEP290 \| License Agreements
Agreement
Shares issued for license fees (in shares) \| shares			75,000
Licensing agreement term			10 years
University Of Massachusetts (UMass) \| miniCEP290 \| License Agreements \| Research and development
Agreement
Payments for license fees		$ 400,000
University Of Massachusetts (UMass) \| miniCEP290 \| License Agreements \| Research and development \| Achievement of Specified Clinical and Regulatory Milestones
Agreement
Shares issued for license fees (in shares) \| shares			75,000	75,000	75,000
Payments for license fees			$ 14,750,000	$ 14,750,000
University Of Massachusetts (UMass) \| miniCEP290 \| License Agreements \| Research and development \| Specified Commercial Sales Milestones Related to a Licensed Product
Agreement
Payments for license fees			$ 48,000,000	$ 48,000,000
University Of Massachusetts (UMass) \| miniCEP290 \| License Agreements \| General and administrative
Agreement
Payments for license fees		$ 18,000
DelSiTech \| License Agreements
Agreement
Termination notice period	60 days
DelSiTech \| Avacincaptad Pegol \| License Agreements
Agreement
Payments for license fees \| €	€ 1,250,000
DelSiTech \| Avacincaptad Pegol \| Achievement Of Specified Commercial Sales Milestones \| License Agreements
Agreement
Payments for license fees \| €	60,000,000				€ 60,000,000
DelSiTech \| Avacincaptad Pegol \| Achievement Of Specified Clinical And Development Milestones \| License Agreements
Agreement
Amount to be paid on achievement of milestone \| €	€ 35,000,000

Stock-Based Compensation and Compensation Plans (Tables)

12 Months Ended

Dec. 31, 2022

Share-Based Payment Arrangement [Abstract]

Summary of the Stock Option Activity Including Weighted Average Exercise Prices, Options Outstanding and Exercisable


	Years ended December 31,
	2022			2021			2020
	Common Stock Options	Weighted Average Exercise Price		Common Stock Options	Weighted Average Exercise Price		Common Stock Options	Weighted Average Exercise Price
Outstanding, December 31, 2021	10,861	$	10.94	8,928	$	9.22	6,780	$	10.89
Granted	3,812	$	19.48	3,204	$	13.03	2,630	$	6.10
Exercised	(2,066)	$	3.84	(646)	$	2.80	(109)	$	2.89
Expired or forfeited	(204)	$	14.08	(625)	$	8.87	(373)	$	19.49
Outstanding, December 31, 2022	12,403	$	14.70	10,861	$	10.94	8,928	$	9.22


	Years ended December 31,
	2022		2021		2020
Options exercisable at December 31, 2022	5,457		5,584		4,462
Weighted average grant date fair value (per share) of options granted during the period	$	13.57	$	10.53	$	4.83

Summary of the Stock Options Outstanding and Exercisable

A summary of the stock options outstanding and exercisable as of December 31, 2022 is as follows (in thousands except exercise prices and weighted average exercise price):


			December 31, 2022
			Options Outstanding			Options Exercisable
Range of Exercise Prices	Total Options Outstanding		Weighted Average Remaining Life (Years)	Weighted Average Exercise Price		Number Exercisable		Weighted Average Exercise Price
$1.20-$2.96	1,266		5.3	$	2.43	1,263		$	2.43
$2.97-$4.88	1,280		6.1	$	4.02	1,021		$	4.08
$4.89-$8.07	2,319		7.8	$	6.73	1,171		$	6.58
$8.08-$15.00	2,644		8.6	$	12.88	705		$	12.67
$15.01-$73.22	4,894		7.9	$	25.43	1,297		$	38.68
	12,403		7.6	$	14.70	5,457		$	13.57

Aggregate Intrinsic Value	$	109,659				$	66,270

Schedule of Cash Proceeds From, and the Aggregate Intrinsic Value of, Stock Options Exercised

Cash proceeds from, and the aggregate intrinsic value of, stock options exercised during the years ended December 31, 2022, 2021 and 2020, respectively, were as follows:


	Years ended December 31,
	2022		2021		2020
Cash proceeds from options exercised	$	7,943	$	1,808	$	314
Aggregate intrinsic value of options exercised	$	23,628	$	4,997	$	393

Summary of the Company's Outstanding Shares of RSU Awards

The following table presents a summary of the Company's outstanding RSU awards granted as of December 31, 2022 (in thousands except weighted average grant-date fair value)


	Restricted Stock Units	Weighted Average Grant-Date Fair Value
Outstanding, December 31, 2021	2,246	$	9.82
Awarded	1,565	$	19.15
Vested	(739)	$	7.81
Expired or forfeited	(46)	$	10.96
Outstanding, December 31, 2022	3,026	$	15.12

Stock-Based Compensation and Compensation Plans - Options Outstanding and Exercisable by Exercise Price and Options Exercised (Details) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) $ / shares shares
Options Outstanding
Total Options Outstanding (in shares) \| shares	12,403
Weighted Average Remaining Life (Years)	7 years 7 months 6 days
Weighted Average Exercise Price (in dollars per share)	$ 14.70
Aggregate Intrinsic Value \| $	$ 109,659
Options Exercisable
Number Exercisable (in shares) \| shares	5,457
Weighted Average Exercise Price (in dollars per share)	$ 13.57
Aggregate Intrinsic Value \| $	$ 66,270
$1.20-$2.96
Range of Exercise Prices
Exercise prices, low end of range (in dollars per share)	$ 1.20
Exercise prices, high end of range (in dollars per share)	$ 2.96
Options Outstanding
Total Options Outstanding (in shares) \| shares	1,266
Weighted Average Remaining Life (Years)	5 years 3 months 18 days
Weighted Average Exercise Price (in dollars per share)	$ 2.43
Options Exercisable
Number Exercisable (in shares) \| shares	1,263
Weighted Average Exercise Price (in dollars per share)	$ 2.43
$2.97-$4.88
Range of Exercise Prices
Exercise prices, low end of range (in dollars per share)	2.97
Exercise prices, high end of range (in dollars per share)	$ 4.88
Options Outstanding
Total Options Outstanding (in shares) \| shares	1,280
Weighted Average Remaining Life (Years)	6 years 1 month 6 days
Weighted Average Exercise Price (in dollars per share)	$ 4.02
Options Exercisable
Number Exercisable (in shares) \| shares	1,021
Weighted Average Exercise Price (in dollars per share)	$ 4.08
$4.89-$8.07
Range of Exercise Prices
Exercise prices, low end of range (in dollars per share)	4.89
Exercise prices, high end of range (in dollars per share)	$ 8.07
Options Outstanding
Total Options Outstanding (in shares) \| shares	2,319
Weighted Average Remaining Life (Years)	7 years 9 months 18 days
Weighted Average Exercise Price (in dollars per share)	$ 6.73
Options Exercisable
Number Exercisable (in shares) \| shares	1,171
Weighted Average Exercise Price (in dollars per share)	$ 6.58
$8.08-$15.00
Range of Exercise Prices
Exercise prices, low end of range (in dollars per share)	8.08
Exercise prices, high end of range (in dollars per share)	$ 15.00
Options Outstanding
Total Options Outstanding (in shares) \| shares	2,644
Weighted Average Remaining Life (Years)	8 years 7 months 6 days
Weighted Average Exercise Price (in dollars per share)	$ 12.88
Options Exercisable
Number Exercisable (in shares) \| shares	705
Weighted Average Exercise Price (in dollars per share)	$ 12.67
$15.01-$73.22
Range of Exercise Prices
Exercise prices, low end of range (in dollars per share)	15.01
Exercise prices, high end of range (in dollars per share)	$ 73.22
Options Outstanding
Total Options Outstanding (in shares) \| shares	4,894
Weighted Average Remaining Life (Years)	7 years 10 months 24 days
Weighted Average Exercise Price (in dollars per share)	$ 25.43
Options Exercisable
Number Exercisable (in shares) \| shares	1,297
Weighted Average Exercise Price (in dollars per share)	$ 38.68

Operating Leases

12 Months Ended

Dec. 31, 2022

Leases [Abstract]

Operating Leases

The Company leases office spaces located in Parsippany, New Jersey and Cranbury, New Jersey under non-cancelable operating lease arrangements. The Company's Parsippany, New Jersey office space lease expires in August 2023 and the Company's Cranbury, New Jersey office space lease expires in February 2024.

For the years ended December 31, 2022, 2021 and 2020, lease and rent expense was $1.4 million, $0.7 million, and $0.6 million, respectively. Cash paid from operating cash flows for amounts included in the measurement of lease liabilities was $1.4 million and $0.7 million for the years ended December 31, 2022 and 2021, respectively. At December 31, 2022, the Company's operating leases had a weighted average remaining lease term of 0.7 years and a weighted average estimated incremental borrowing rate of 5.6%.

The following presents the maturity of the Company's operating lease liabilities as of December 31, 2022:


	December 31, 2022

2023	1,216
2024	11

Total minimum lease payments	1,227
Less imputed interest	(27)
Present value of minimum lease payments	1,200
Less current portion	1,189
Total long-term operating lease liabilities	$	11

Audit Information	12 Months Ended
Audit Information	Dec. 31, 2022
Auditor Information [Abstract]
Auditor Firm ID	42
Auditor Name	Ernst & Young LLP
Auditor Location	Iselin, New Jersey

Stock-Based Compensation and Compensation Plans - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended						12 Months Ended			120 Months Ended
	Sep. 30, 2021	Feb. 28, 2021	Mar. 31, 2020	Jun. 30, 2016	Apr. 30, 2016	Aug. 31, 2013	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2022	Feb. 28, 2023	Oct. 31, 2019
Stock Option and Compensation Plans
Options outstanding (in shares)							11,847,000			11,847,000
Weighted-average exercise price of options (in dollars per share)							$ 14.66			$ 14.66
Weighted-average remaining contractual life of options							7 years 6 months
Aggregate intrinsic value							$ 106,200			$ 106,200
Share-based compensation expense							26,676	$ 11,245	$ 8,323
Stock options
Stock Option and Compensation Plans
Share-based compensation expense							16,100	6,500	4,700
Unrecognized compensation costs							$ 66,900			$ 66,900
Remaining weighted average period							3 years 2 months 12 days
ESPP
Stock Option and Compensation Plans
Number of shares of common stock available for issuance under the Plan (in shares)							712,394			712,394
Purchase price of common stock as percentage of fair market value					85.00%
Offering period				6 months	6 months
Share-based compensation expense							$ 400	$ 200
Unrecognized compensation costs							$ 100			$ 100
Remaining weighted average period							2 months 12 days
Common stock issued (in shares)							41,016	51,951
Proceeds from stock plans							$ 500	$ 300
Restricted stock units
Stock Option and Compensation Plans
Share-based compensation expense								0
RSUs expected to vest (in shares)							2,788,000			2,788,000
Weighted-average fair value of RSUs expected to vest (in dollars per share)							$ 15.12			$ 15.12
Aggregate intrinsic value of RSUs expected to vest							$ 59,700			$ 59,700
Total fair value vested							5,800
Employees \| Restricted stock units
Stock Option and Compensation Plans
Share-based compensation expense							$ 10,200	$ 4,600	$ 3,300
Remaining weighted average period							3 years 3 months 18 days
Unrecognized compensation costs, net of estimated forfeitures							$ 36,400			$ 36,400
Maximum \| ESPP
Stock Option and Compensation Plans
Number of shares reserved for issuance under the plan up to (in shares)					1,000,000
2013 Plan
Stock Option and Compensation Plans
Number of shares of common stock available for issuance under the Plan (in shares)							166,000			166,000
Annual increase in shares reserved for issuance under the Plan (in shares)						2,542,372
Annual increase in shares reserved for issuance under the Plan (as a percent)						4.00%
Increase in number of shares available under the Plan (in shares)							2,542,000			18,166,000
2013 Plan \| Maximum
Stock Option and Compensation Plans
Number of shares reserved for issuance under the plan up to (in shares)						3,359,641
2007 Plan
Stock Option and Compensation Plans
Number of shares of common stock available for issuance under the Plan (in shares)						739,317
2019 Inducement Plan \| Stock options
Stock Option and Compensation Plans
Number of shares reserved for issuance under the plan up to (in shares)												1,000,000
Number of shares of common stock available for issuance under the Plan (in shares)							791,000			791,000
Increase in number of shares available under the Plan (in shares)	1,000,000	600,000	1,000,000
2019 Inducement Plan \| Stock options \| Subsequent Event
Stock Option and Compensation Plans
Number of shares reserved for issuance under the plan up to (in shares)											2,000,000

Operating Leases (Tables)

12 Months Ended

Dec. 31, 2022

Leases [Abstract]

Schedule of Operating Lease Liability Maturities

The following presents the maturity of the Company's operating lease liabilities as of December 31, 2022:


	December 31, 2022

2023	1,216
2024	11

Total minimum lease payments	1,227
Less imputed interest	(27)
Present value of minimum lease payments	1,200
Less current portion	1,189
Total long-term operating lease liabilities	$	11

Commitments and Contingencies - IC-500 - Former Equity Holders of Inception 4 (Details) - Inception 4 shares in Millions	12 Months Ended
	Dec. 31, 2022 USD ($) shares
Schedule of Commitments and Contingencies [Line Items]
Contingent consideration	$ 105,000,000
Share price calculation base, period (in days)	5 days
Contingently issuable shares, asset acquisition (in shares) \| shares	7.2
Contingently issuable shares, asset acquisition, as a percentage of total shares outstanding	19.90%
GA
Schedule of Commitments and Contingencies [Line Items]
Clinical and marketing approval milestones	$ 45,000,000
Wet AMD
Schedule of Commitments and Contingencies [Line Items]
Clinical and marketing approval milestones	$ 60,000,000

Licensing and Commercialization Agreements - Zimura License Agreement With Archemix Corp. (Details) - Archemix - C5 Licensed Product - License Agreements	1 Months Ended			8 Months Ended
	Oct. 31, 2020 USD ($)	Mar. 31, 2020 USD ($)	Sep. 30, 2011 USD ($) shares	Oct. 31, 2020 USD ($) milestone_payment	Dec. 31, 2022 USD ($)
Agreement
Licensing agreement term			12 years
Achievement of Specified Clinical and Regulatory Milestones
Agreement
Payments for license fees	$ 6,000,000	$ 1,000,000	$ 1,000,000	$ 9,000,000
Number of milestone payments \| milestone_payment				2
Trial data period				12 months
Amount to be paid on achievement of milestone					$ 50,500,000
Achievement of Specified Clinical and Regulatory Milestones \| Maximum
Agreement
Amount to be paid on achievement of milestone			$ 50,500,000
Achievement of Specified Clinical and Regulatory Milestones \| Series A Preferred Stock
Agreement
Shares issued for license fees (in shares) \| shares			2,000,000
Achievement of Specified Clinical and Regulatory Milestones \| Series B Preferred Stock
Agreement
Shares issued for license fees (in shares) \| shares			500,000
First Indication
Agreement
Amount to be paid on achievement of milestone			$ 24,500,000		24,500,000
Second and Third Indication
Agreement
Amount to be paid on achievement of milestone			23,500,000		23,500,000
Sustained Delivery Applications
Agreement
Amount to be paid on achievement of milestone			2,500,000		2,500,000
Achievement of Specified Commercial Milestones
Agreement
Amount to be paid on achievement of milestone					$ 22,500,000
Achievement of Specified Commercial Milestones \| Maximum
Agreement
Amount to be paid on achievement of milestone			$ 22,500,000

Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies ACP - Archemix Corp. The Company is party to an agreement with Archemix Corp. (“Archemix”) under which the Company in-licensed rights in certain patents, patent applications and other intellectual property related to ACP and pursuant to which the Company may be required to pay sublicense fees and make milestone payments (the “C5 License Agreement”). Under the C5 License Agreement, for each anti-C5 aptamer product that the Company may develop under the agreement, including ACP, the Company is obligated to make additional payments to Archemix of up to an aggregate of $50.5 million if the Company achieves specified development, clinical and regulatory milestones, with $24.5 million of such payments relating to a first indication, $23.5 million of such payments relating to second and third indications and $2.5 million of such payments relating to sustained delivery applications. Under the C5 License Agreement, the Company is also obligated to make additional payments to Archemix of up to an aggregate of $22.5 million if the Company achieves specified commercial milestones based on net product sales of all anti-C5 products licensed under the agreement. The Company is also obligated to pay Archemix a double-digit percentage of specified non-royalty payments the Company may receive from any sublicensee of its rights under the C5 License Agreement. The Company is not obligated to pay Archemix a running royalty based on net product sales in connection with the C5 License Agreement. ACP Sustained Release Delivery Technology - DelSiTech Under the DelSiTech License Agreement with DelSiTech, the Company is obligated to make payments up to an aggregate of €35.0 million, if the Company achieves specified clinical and development milestones with respect to a Licensed Product. In addition, the Company is also obligated to pay DelSiTech up to an aggregate of €60.0 million if the Company achieves specified commercial sales milestones with respect to worldwide net sales of the Licensed Product. The Company is also obligated to pay DelSiTech royalties at a low single-digit percentage of net sales of the Licensed Product. The royalties payable by the Company are subject to reduction under specified circumstances. miniCEP290 Program - University of Massachusetts Under its exclusive license agreement with the University of Massachusetts (“UMass”) for its miniCEP290 program, which targets LCA10, which is associated with mutations in the CEP290 gene, the Company is obligated to pay UMass up to an aggregate of $14.75 million in cash and issue up to 75,000 shares of common stock of the Company if the Company achieves specified clinical and regulatory milestones with respect to a licensed product. In addition, the Company is obligated to pay UMass up to an aggregate of $48.0 million if the Company achieves specified commercial sales milestones with respect to a licensed product. The Company is also obligated to pay UMass royalties at a low single-digit percentage of net sales of licensed products. If the Company or any of its affiliates sublicenses any of the licensed patent rights or know-how to a third party, the Company will be obligated to pay UMass a high single-digit to a mid-tens percentage of the consideration received in exchange for such sublicense, with the applicable percentage based upon the stage of development of the licensed products at the time the Company or the applicable affiliate enters into the sublicense. If the Company receives a priority review voucher from the FDA in connection with obtaining marketing approval for a licensed product, and the Company subsequently uses such priority review voucher in connection with a different product candidate outside the scope of the agreement, the Company will be obligated to pay UMass a low-tens percentage of the fair market value of the priority review voucher at the time of approval of such product candidate and a low-twenties percentage of the fair market value of the priority review voucher at the time of achievement of a specified commercial sales milestone for such product candidate. In addition, if the Company sells such a priority review voucher to a third party, the Company will be obligated to pay UMass a low-thirties percentage of any consideration received from such third party in connection with such sale. IC-500 - Former Equityholders of Inception 4 Under the agreement and plan of merger between the Company and Inception 4, Inc. (“Inception 4”), pursuant to which the Company acquired IC-500 and its other HtrA1 inhibitors (the “Inception 4 Merger Agreement”), the Company is obligated to make payments to the former equityholders of Inception 4 of up to an aggregate of $105 million, subject to the terms and conditions of the Inception 4 Merger Agreement, if the Company achieves certain specified clinical and regulatory milestones with respect to IC-500 or any other product candidate from its HtrA1 inhibitor program, with $45 million of such potential payments relating to GA and $60 million of such potential payments relating to wet AMD. Under the Inception 4 Merger Agreement, the Company does not owe any commercial milestones or royalties based on net sales. The future milestone payments will be payable in the form of shares of the Company's common stock, calculated based on the price of its common stock over a five-trading day period preceding the achievement of the relevant milestone, unless and until the issuance of such shares would, together with all other shares issued in connection with the acquisition, exceed an overall maximum limit of approximately 7.2 million shares, which is equal to 19.9% of the number of issued and outstanding shares of the Company's common stock as of the close of business on the business day prior to the closing date of the Inception 4 acquisition, and will be payable in cash thereafter. The Inception 4 Merger Agreement also includes customary indemnification obligations to the former equityholders of Inception 4, including for breaches of the representations and warranties, covenants and agreements of the Company and its subsidiaries (other than Inception 4) in the Inception 4 Merger Agreement. Employment Contracts The Company also has letter agreements with certain employees that require the funding of a specific level of payments if certain events, such as a termination of employment in connection with a change in control or termination of employment by the employee for good reason or by the Company without cause, occur. Contract Service Providers In addition, in the course of normal business operations, the Company has agreements with contract service providers to assist in the performance of the Company’s research and development and manufacturing activities. Expenditures to CROs and CDMOs represent significant costs in preclinical and clinical development. Subject to required notice periods and the Company’s obligations under binding purchase orders and any cancellation fees that the Company may be obligated to pay, the Company can elect to discontinue the work under these agreements at any time. Legal Proceedings On January 11, 2017, a putative class action lawsuit was filed against the Company and certain of its current and former executive officers in the United States District Court for the Southern District of New York, captioned Frank Micholle v. Ophthotech Corporation, et al., No. 1:17-cv-00210. On March 9, 2017, a related putative class action lawsuit was filed against the Company and the same group of its current and former executive officers in the United States District Court for the Southern District of New York, captioned Wasson v. Ophthotech Corporation, et al., No. 1:17-cv-01758. These cases were consolidated on March 13, 2018. On June 4, 2018, the lead plaintiff filed a consolidated amended complaint (the “CAC”). The CAC purports to be brought on behalf of shareholders who purchased the Company’s common stock between March 2, 2015 and December 12, 2016. The CAC generally alleges that the Company and certain of its officers violated Sections 10(b) and/or 20(a) of the Securities Exchange Act of 1934 and Rule 10b-5 promulgated thereunder by making allegedly false and/or misleading statements concerning the results of the Company’s Phase 2b trial and the prospects of the Company’s Phase 3 trials for Fovista in combination with anti-VEGF agents for the treatment of wet AMD. The CAC seeks unspecified damages, attorneys’ fees, and other costs. The Company and individual defendants filed a motion to dismiss the CAC on July 27, 2018. On September 18, 2019, the court issued an order dismissing some, but not all, of the allegations in the CAC. On November 18, 2019, the Company and the individual defendants filed an answer to the complaint. On June 12, 2020, the lead plaintiff filed a motion for class certification. On August 11, 2020, the defendants filed a notice of non-opposition to lead plaintiff's motion for class certification. On April 23, 2021, the court issued an order staying the action until July 1, 2021, 10 days after a mediation scheduled for June 21, 2021. On July 1, 2021, following the June 21, 2021 mediation, the parties notified the court that they had reached an agreement in principle to settle the class action. On September 8, 2021, the parties executed a settlement agreement and submitted the agreement to the court for approval. Under the terms of the settlement agreement, the Company agreed to pay $29 million, which includes the attorneys' fees and costs and expenses for the plaintiffs' counsel. On March 17, 2022, the court provided a preliminary approval of the settlement. In April 2022, the Company’s insurance carriers paid the full amount of the settlement directly to the plaintiffs’ escrow account. On September 16, 2022, the court granted final approval of the settlement. This settlement did not have a material impact on the Company’s financial condition. On August 31, 2018, a shareholder derivative action was filed against current and former members of the Company's board of directors and certain current and former officers of the Company in the United States District Court for the Southern District of New York, captioned Luis Pacheco v. David R. Guyer, et al., Case No. 1:18-cv-07999. The complaint, which is based substantially on the facts alleged in the CAC, alleges that the defendants breached their fiduciary duties to the Company and wasted the Company's corporate assets by failing to oversee the Company's business, and also alleges that the defendants were unjustly enriched as a result of the alleged conduct, including through receipt of bonuses, stock options and similar compensation from the Company, and through sales of the Company's stock between March 2, 2015 and December 12, 2016. The complaint purports to seek unspecified damages on the Company's behalf, attorneys’ fees, and other costs, as well as an order directing the Company to reform and improve its corporate governance and internal procedures to comply with applicable laws, including submitting certain proposed amendments to the Company's corporate charter, bylaws and corporate governance policies for vote by the Company's stockholders. On December 14, 2018, the Company filed a motion to dismiss the complaint. On September 19, 2019, the court denied its motion to dismiss this complaint. This matter was subsequently referred to a special litigation committee (“SLC”) of the Company's board of directors. On February 18, 2020, the Company filed an answer to the complaint. The Company and the plaintiff agreed to stay this litigation while the SLC conducts its investigation. On May 4, 2020, the court approved the stipulation and stayed the litigation through November 1, 2020. By agreement of the parties, the court has since extended the stay through June 26, 2021. The Company also entered into tolling agreements with the defendant directors to December 2022. On January 27, 2022, the parties executed a settlement agreement (the “Stipulation of Settlement”). On November 3, 2022, the court issued an order preliminarily approving the settlement. On January 27, 2023, the court granted final approval of the settlement. This settlement did not have a material impact on the Company's financial condition. On October 16, 2018, the Company’s board of directors received a shareholder demand to investigate and commence legal proceedings against certain members of the Company’s board of directors. The demand alleges facts that are substantially similar to the facts alleged in the CAC and the Pacheco complaint and asserts claims that are substantially similar to the claims asserted in the Pacheco complaint. On January 30, 2019, the Company’s board of directors received a second shareholder demand from a different shareholder to investigate and commence legal proceedings against certain current and former members of the Company’s board of directors based on allegations that are substantially similar to the allegations contained in the first demand letter. These shareholder demands were referred to a demand review committee of the Company's board of directors. On May 6, 2021, the shareholders who served the October 16, 2018 demand filed a shareholder derivative action against current and former members of the Company’s board of directors and certain current and former officers of the Company in the New York Supreme Court, captioned Brian Ferber et al., derivatively on behalf of Ophthotech Corporation v. Axel Bolte et al., Index No. 154462/2021. The complaint asserts the same claims as those asserted in the Pacheco complaint and is based on factual allegations that are materially similar to the allegations in the Pacheco complaint. On June 22, 2021, the parties filed a stipulation staying the Ferber action until 60 days after the SLC concludes its investigation. On January 27, 2022, the parties executed the Stipulation of Settlement referred to above, settling the matter. On November 3, 2022, the court issued an order preliminarily approving the settlement. On January 27, 2023, the court granted final approval of the settlement. The settlement did not have a material impact on the Company's financial condition.

Net Income (Loss) Per Common Share - Schedule of Potentially Dilutive Securities (Details) - shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive securities excluded from computation of earnings per share (in shares)	15,428,570	13,107,752	10,886,081
Stock options outstanding
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive securities excluded from computation of earnings per share (in shares)	12,402,629	10,861,483	8,927,698
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive securities excluded from computation of earnings per share (in shares)	3,025,941	2,246,269	1,958,383

Fair Value Measurements - (Tables)

12 Months Ended

Dec. 31, 2022

Fair Value Disclosures [Abstract]

Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis


	Fair Value Measurement Using
	Quoted prices in active markets for identical assets (Level 1)		Significant other observable inputs (Level 2)		Significant unobservable inputs (Level 3)
Assets
Investments in money market funds*	$	475,689	$	—	$	—

Investments in U.S. Treasury securities	$	27,423	$	—	$	—
Investments in corporate debt securities	$	—	$	109,129	$	—
Investments in U.S. government agency securities	—		$	9,669	—
Investments in asset-backed securities	$	—	$	19,297	$	—
Investments in supranational securities	$	—	$	5,013	$	—


	Fair Value Measurement Using
	Quoted prices in active markets for identical assets (Level 1)		Significant other observable inputs (Level 2)		Significant unobservable inputs (Level 3)
Assets
Investments in money market funds*	$	251,488	$	—	$	—
Investments in U.S. Treasury securities	$	18,185	$	—	$	—
Investments in corporate debt securities	$	—	$	82,081	$	—
Investments in asset-backed securities	$	—	$	15,995	$	—
Investments in supranational securities	—		4,041		—

*Investments in money market funds are reflected in cash and cash equivalents in the accompanying Consolidated Balance Sheets.

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, shares issued (in shares)	136,639,687	115,277,012
Common stock, shares outstanding (in shares)	136,639,687	115,277,012

Stock-Based Compensation and Compensation Plans - Summary of Stock Option Activity (Details) - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Common Stock Options
Outstanding at beginning of year (in shares)	10,861	8,928	6,780
Granted (in shares)	3,812	3,204	2,630
Exercised (in shares)	(2,066)	(646)	(109)
Expired or forfeited (in shares)	(204)	(625)	(373)
Outstanding at end of year (in shares)	12,403	10,861	8,928
Weighted Average Exercise Price
Outstanding at beginning of year (in dollars per share)	$ 10.94	$ 9.22	$ 10.89
Granted (in dollars per share)	19.48	13.03	6.10
Exercised (in dollars per share)	3.84	2.80	2.89
Expired or forfeited (in dollars per share)	14.08	8.87	19.49
Outstanding at end of year (in dollars per share)	$ 14.70	$ 10.94	$ 9.22
Options exercisable at end of year (in shares)	5,457	5,584	4,462
Weighted average grant date fair value (per share) of options granted during the period (in dollars per share)	$ 13.57	$ 10.53	$ 4.83

Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Property and Equipment
Property and equipment, gross	$ 2,077	$ 1,341
Accumulated depreciation	(1,131)	(993)
Property and equipment, net	946	348
Depreciation expense	$ 138	39	$ 143
Minimum
Property and Equipment
Useful life	3 years
Maximum
Property and Equipment
Useful life	10 years
Research, manufacturing and clinical equipment
Property and Equipment
Property and equipment, gross	$ 548	283
Research, manufacturing and clinical equipment \| Minimum
Property and Equipment
Useful life	5 years
Research, manufacturing and clinical equipment \| Maximum
Property and Equipment
Useful life	10 years
Computer, software and other office equipment
Property and Equipment
Useful life	5 years
Property and equipment, gross	$ 1,201	933
Furniture and fixtures
Property and Equipment
Useful life	7 years
Property and equipment, gross	$ 203	0
Automobile
Property and Equipment
Useful life	5 years
Property and equipment, gross	$ 125	$ 125

Net Income (Loss) Per Common Share - Narrative (Details) - shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive securities excluded from computation of earnings per share (in shares)	15,428,570	13,107,752	10,886,081
Pre-funded warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive securities excluded from computation of earnings per share (in shares)	0	3,164,280

Income Taxes - Schedule of Components of Income Tax (Benefit) Expense (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Current:
Federal	$ 0	$ 0	$ 0
State	0	0	(3,695,000)
Deferred:
Federal	0	0	0
State	0	0	0
Income tax benefit	$ 0	$ 0	$ (3,695,000)

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details