0001410939-22-000015 | 10-K | XBRL Viewer

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Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets
Cash and cash equivalents	$ 261,447	$ 66,373
Available for sale securities	120,302	143,674
Prepaid expenses and other current assets	5,739	4,791
Income tax receivable	0	1,765
Total current assets	387,488	216,603
Property and equipment, net	348	26
Right-of-use assets, net	1,522	120
Other assets	0	5
Total assets	389,358	216,754
Current liabilities
Accrued research and development expenses	14,403	12,284
Accounts payable and accrued expenses	12,856	12,792
Lease liability, current	952	54
Total current liabilities	28,211	25,130
Lease liability, non-current	619	61
Total liabilities	28,830	25,191
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, 115,277,012 and 90,120,797 shares issued and outstanding at December 31, 2021 and December 31, 2020, respectively	115	90
Additional paid-in capital	1,040,098	756,543
Accumulated deficit	(679,595)	(565,073)
Accumulated other comprehensive income	(90)	3
Total stockholders' equity	360,528	191,563
Total liabilities and stockholders' equity	$ 389,358	$ 216,754

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2021	Dec. 31, 2020
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)	115,277,012	90,120,797
Common stock, shares outstanding (in shares)	115,277,012	90,120,797

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating expenses:
Research and development	$ 85,068	$ 62,784	$ 39,644
General and administrative	29,689	25,952	21,628
Total operating expenses	114,757	88,736	61,272
Loss from operations	(114,757)	(88,736)	(61,272)
Interest income	245	500	2,151
Other income (expense), net	(10)	(6)	151
Loss before income tax benefit	(114,522)	(88,242)	(58,970)
Income tax benefit	0	3,695	111
Net loss	$ (114,522)	$ (84,547)	$ (58,859)
Net loss per common share:
Basic (in dollars per share)	$ (1.12)	$ (1.14)	$ (1.39)
Dilutive (in dollars per share)	$ (1.12)	$ (1.14)	$ (1.39)
Weighted average common shares outstanding:
Basic (in shares)	101,866	74,185	42,224
Diluted (in shares)	101,866	74,185	42,224

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Net loss	$ (114,522)	$ (84,547)	$ (58,859)
Other comprehensive income
Unrealized gain (loss) on available-for-sale securities, net of tax	(93)	3	0
Other comprehensive income (loss)	(93)	3	0
Comprehensive loss	$ (114,615)	$ (84,544)	$ (58,859)

- 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

Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Underwritten Offering	Private Placement	Junior Series A Preferred Stock	Common Stock	Common Stock Underwritten Offering	Common Stock Private Placement	Additional paid-in capital	Additional paid-in capital Underwritten Offering	Additional paid-in capital Private Placement	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)
Balance at beginning of period (in shares) at Dec. 31, 2018				0	41,397
Balance at beginning of period at Dec. 31, 2018	$ 123,959			$ 0	$ 41			$ 545,585			$ (421,667)	$ 0
Increase (Decrease) in Stockholders' Equity
Issuance of common stock and pre-funded warrants, net (in shares)					7,750
Issuance of common stock and pre-funded warrants, net	42,565				$ 8			42,557
Issuance of common stock in connection with license acquisition (in shares)					75
Issuance of common stock in connection with license acquisition	85							85
Issuance of common stock under employee stock compensation plan (in shares)					405
Issuance of common stock under employee stock compensation plans	273				$ 1			272
Share-based compensation	9,180							9,180
Net loss	(58,859)										(58,859)
Unrealized gain (loss) on available-for-sale securities, net of tax	0
Balance at end 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	8,649
Issuance of common stock and pre-funded warrants, net		$ 116,883	$ 33,237			$ 28	$ 9		$ 116,855	$ 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
Issuance of common stock under the excercise of pre-funded warrants (in shares)					2,500
Issuance of common stock under the excercise of pre-funded warrants	0				$ 2			(2)
Share-based compensation	8,323							8,323
Net loss	(84,547)										(84,547)
Unrealized gain (loss) 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 (loss) 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)

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating Activities
Net loss	$ (114,522)	$ (84,547)	$ (58,859)
Adjustments to reconcile net loss to net cash (used in) provided by operating activities:
Depreciation	39	143	162
Amortization of premium and discounts on investment securities	1,182	462	0
Gain on sale of property and equipment	0	0	(150)
Share-based compensation	11,245	8,323	9,180
Change in working capital	54	0	0
Stock-based consideration in connection with license acquisition	0	0	85
Changes in operating assets and liabilities:
Income tax receivable	1,765	0	1,765
Other assets			0
Prepaid expense and other assets	(943)	(2,742)	45
Accrued interest receivable	438	(323)	0
Accrued research and development expenses	2,119	5,424	(477)
Accounts payable and accrued expenses	64	7,163	(241)
Net cash used in operating activities	(98,559)	(66,097)	(48,490)
Investing Activities
Purchase of marketable securities	(142,821)	(143,810)	0
Maturities of marketable securities	164,480	0	0
Purchase of property and equipment	(361)	0	0
Proceeds from sale of assets	0	0	150
Net cash provided by (used in) investing activities	21,298	(143,810)	150
Financing Activities
Proceeds from employee stock plan purchases and stock option exercises	2,016	461	273
Net cash provided by financing activities	272,335	150,581	42,838
Net change in cash and cash equivalents	195,074	(59,326)	(5,502)
Cash and cash equivalents
Beginning of period	66,373	125,699	131,201
End of period	261,447	66,373	125,699
Supplemental disclosure of cash paid
Income taxes received, net	(1,765)	(3,327)	(1,893)
Supplemental disclosures of non-cash information related to investing activities
Supplemental disclosures of non-cash information related to investing activities	(93)	3	0
Operating right-of-use assets obtained in exchange for lease obligations	2,086	166	1,469
Public Stock Offering
Financing Activities
Proceeds from issuance of common stock and pre-funded warrants, net, and related to acquisition	270,319	116,883	42,565
Private Placement
Financing Activities
Proceeds from issuance of common stock and pre-funded warrants, net, and related to acquisition	$ 0	$ 33,237	$ 0

Business	12 Months Ended
Business	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business	Business Description of Business and Organization IVERIC bio, Inc. (“the Company” or “IVERIC”) 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 Zimura® (avacincaptad pegol), a complement C5 inhibitor. It is currently targeting the following diseases with Zimura: •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 that precedes GA; 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 July 2021, the Company completed patient enrollment for GATHER2, its Phase 3 clinical trial evaluating the safety and efficacy of Zimura for the treatment of GA secondary to AMD. The Company has also received a written agreement from the U.S. Food and Drug Administration (“FDA”) under a Special Protocol Assessment ("SPA") for the overall design of GATHER2. The Company expects topline data from the GATHER2 trial to become available during the second half of 2022, approximately one year after the enrollment of the last patient plus the time needed for database lock and analysis. The Company also plans to initiate a Phase 3 clinical trial evaluating Zimura for patients with intermediate AMD during the second half of 2022. In addition to Zimura, the Company is developing its preclinical product candidate IC-500, a High temperature requirement A serine peptidase 1 protein (“HtrA1”) inhibitor, for GA and potentially other age-related retinal diseases. Based on current timelines, the Company expects to submit an investigational new drug application to the FDA for IC-500 in mid-2023. The Company’s portfolio also includes two preclinical stage gene therapy product candidates (IC-100 and IC-200) and 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”): •rhodopsin-mediated autosomal dominant retinitis pigmentosa (“RHO-adRP”), which is characterized by progressive and severe bilateral loss of vision leading to blindness; •IRDs associated with mutations in the BEST1 gene, including Best vitelliform macular dystrophy (“Best disease”); •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. As the Company focuses its efforts on and prioritize the development and potential commercialization of Zimura, it has been considering its development options for IC-100 and IC-200, which the Company has been developing for RHO-adRP and BEST1-related IRDs, respectively. It currently plans to seek a collaborator for the future development and potential commercialization of these product candidates.

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2021

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 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, 2021, the Company had cash, cash equivalents and available-for-sale securities of approximately $381.7 million. The Company believes that its cash, cash equivalents and available-for-sale securities as of December 31, 2021 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, 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 Zimura 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 Zimura. The Company has engaged one additional third-party manufacturer to provide drug substance for Zimura and one additional third-party manufacturer to provide fill/finish services for clinical supplies of Zimura. 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 Zimura. 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 Zimura. The Company currently relies exclusively upon a single third-party contract manufacturer for IC-100 and IC-200, and also relies on sole-source suppliers for certain starting materials used in the manufacture of such product candidates. 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 COVID-19 pandemic, 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.

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.

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.

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.

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 academic research collaborators, 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.

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.

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.

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, 2021, 2020 and 2019:


	Years ended December 31,
	2021	2020	2019
Expected common stock price volatility	114%	118%	110%
Risk-free interest rate	0.31%-1.22%	0.22%-1.34%	1.38%-2.54%
Expected term of options (years)	5.2	4.6	4.8
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,
	2021		2020		2019
Research and development	$	6,522	$	4,166	$	4,260
General and administrative	4,723		4,157		4,920
Total	$	11,245	$	8,323	$	9,180

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.

Common Stock	12 Months Ended
Common Stock	Dec. 31, 2021
Equity [Abstract]
Common Stock	Common Stock 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 18
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496189-112644

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496158-112644

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496180-112644

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496158-112644

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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+ Details

Net Income (Loss) Per Common Share

12 Months Ended

Dec. 31, 2021

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, 2021 and 2020, the Company had 3,164,280 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,
	2021		2020		2019
Basic and diluted net income (loss) per common share calculation:
Net loss	$	(114,522)	$	(84,547)	$	(58,859)


Weighted average common shares outstanding - dilutive	101,866		74,185		42,224
Net loss per common share - basic and diluted	$	(1.12)	$	(1.14)	$	(1.39)

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,
	2021	2020	2019
Stock options outstanding	10,861	8,928	6,780
Restricted stock units	2,246	1,958	1,481
Total	13,107	10,886	8,261

Cash, Cash Equivalents and Available for Sale Securities

12 Months Ended

Dec. 31, 2021

Cash and Cash Equivalents [Abstract]

Cash, Cash Equivalents and Available for Sale Securities

Cash, Cash Equivalents and Available-for-Sale Securities

As of December 31, 2021 and December 31, 2020 the Company had cash and cash equivalents of approximately $261.4 million and $66.4 million, respectively. Cash and cash equivalents at December 31, 2021 and December 31, 2020 included cash of $9.9 million and $8.4 million, respectively. As of December 31, 2021 and December 31, 2020, cash and cash equivalents also included $251.5 million and $58.0 million, respectively, of investments in money market funds.

As of December 31, 2021 and December 31, 2020, the Company held available-for-sale securities of approximately $120.3 million and $143.7 million, respectively, all of which have maturities of less than one year.

As of December 31, 2021, the Company determined that there were no credit losses in fair value of its investments. 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, 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


	As of As of December 31, 2020
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
U.S. Treasury securities	$	54,225	$	8	—		$	54,233
Corporate debt securities	79,282		4		(10)		79,276
Asset-backed securities	10,164		1		—		10,165

Total	$	143,671	$	13	$	(10)	$	143,674

Fair Value Measurements

12 Months Ended

Dec. 31, 2021

Fair Value Disclosures [Abstract]

Fair Value Measurements

The Company classifies its marketable debt 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.

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, 2021:


	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	$	—


	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*	$	58,042	$	—	$	—
Investments in U.S. Treasury securities	$	54,233	$	—	$	—
Investments in corporate debt securities	$	—	$	79,275	$	—
Investments in asset-backed securities	$	—	$	10,166	$	—

*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, 2021 or December 31, 2020.

Licensing and Commercialization Agreements	12 Months Ended
Licensing and Commercialization Agreements	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Licensing and Commercialization Agreements	Licensing and Commercialization Agreements Zimura 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 Zimura, 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 Zimura, 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. RHO-adRP License Agreement with the University of Florida Research Foundation and the University of Pennsylvania In June 2018, the Company entered into an exclusive global license agreement (the "RHO-adRP License Agreement") with the University of Florida Research Foundation, Incorporated ("UFRF") and the University of Pennsylvania ("Penn" and collectively with UFRF, the "Licensors"). Under the agreement, the Licensors granted the Company a worldwide, exclusive license under specified patent rights and a worldwide, non-exclusive license under specified know-how, including specified preclinical data, to manufacture, develop and commercialize certain AAV gene therapy products for the treatment of rhodopsin-mediated diseases. The rights granted under the RHO-adRP License Agreement included certain patent rights covering IC-100, the Company's novel AAV gene therapy product candidate intended to treat RHO-adRP. Under the agreement, the Company agreed to pay an annual license maintenance fee in the low double-digit thousands of dollars, which will be payable on an annual basis until the first commercial sale of a licensed product. In addition, the Company agreed to reimburse UFRF for the costs and expenses of patent prosecution and maintenance related to the licensed patent rights. The Company further agreed to pay UFRF, on behalf of both Licensors, up to an aggregate of $23.5 million if the Company achieves specified clinical, marketing approval and reimbursement approval milestones with respect to a licensed product and additionally, up to an aggregate of $70.0 million if the Company achieves specified commercial sales milestones with respect to a licensed product. The Company is also obligated to pay UFRF, on behalf of both Licensors, royalties at a low single-digit percentage of net sales of licensed products. Such royalties are subject to customary reductions for lack of patent coverage and loss of regulatory exclusivity. In addition, such royalties with respect to any licensed product in any country may be offset by a specified portion of any royalty payments actually paid by the Company in such country under third-party licenses for patent rights or other intellectual property rights that are necessary to manufacture, develop and commercialize the licensed product in such country. The Company's obligation to pay royalties under the RHO-adRP License Agreement will continue on a licensed product-by-licensed product and country-by-country basis until the latest of: •the expiration of the last-to-expire licensed patent rights covering a licensed product in the country of sale; •the expiration of regulatory exclusivity covering a licensed product in the country of sale; and •ten years from the first commercial sale of the applicable licensed product in the country of sale. Beginning on the earlier of (i) the calendar year following the first commercial sale of a licensed product and (ii) the first business day of 2031, the Company is also obligated to pay certain minimum royalties, not to exceed an amount in the low hundreds of thousands of dollars on an annual basis, which minimum royalties are creditable against the Company's royalty obligation with respect to net sales of licensed products due for the year in which the minimum royalty is paid. In addition, if the Company or an affiliate sublicenses any of the licensed patent rights to a third party, the Company will be obligated to pay UFRF, on behalf of both Licensors, a low double-digit percentage of the consideration received in exchange for such 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 the Company subsequently uses such priority review voucher in connection with a different product candidate, the Company will be obligated to pay UFRF, on behalf of both Licensors, aggregate payments in the low double-digit millions of dollars based on certain marketing approval and commercial sales milestones with respect to such other product candidate. If the Company sells such priority review voucher to a third party, it will be obligated to pay UFRF, on behalf of both licensors, a low double-digit percentage of any consideration received from such third party in connection with such sale. Unless earlier terminated by the Company, the RHO-adRP License Agreement will expire upon the expiration of the Company’s obligation to pay royalties to UFRF on net sales of licensed products. The Company may terminate the agreement at any time for any reason upon prior written notice to UFRF. Penn or UFRF may terminate the RHO-adRP License Agreement in the event of certain breaches by the Company or in the event of certain insolvency events regarding the Company. BEST1 License Agreement with University of Pennsylvania and University of Florida Research Foundation In April 2019, the Company entered into an exclusive global license agreement (the "BEST1 License Agreement") with Penn and UFRF. Under the BEST1 License Agreement, Penn and UFRF granted the Company a worldwide, exclusive license under specified patent rights and specified know-how and a worldwide, non-exclusive license under other specified know-how to research, develop, manufacture and commercialize certain AAV gene therapy products, including IC-200, for the treatment of Best disease and other BEST1-related IRDs. In May 2019, the Company paid Penn, for the benefit of the Licensors, a $0.2 million upfront license issuance fee, which was recorded as a research and development expense, and the Company paid UFRF accrued patent prosecution expenses of approximately $18 thousand, which was recorded as a general and administrative expense. The Company has also agreed to pay Penn, for the benefit of the Licensors, an annual license maintenance fee in the low double-digit thousands of dollars, which will be payable on an annual basis until the first commercial sale of a licensed product. In addition, the Company have agreed to pay Penn, for the benefit of the Licensors, a one-time patent grant fee in the low triple-digit thousands of dollars, upon the issuance of a U.S. patent that claims inventions disclosed in the licensed patent rights or know-how or inventions generated under certain related sponsored research agreements with Penn or UFRF, and that is exclusively licensed to the Company. Furthermore, it has agreed to reimburse Penn and UFRF for the costs and expenses of patent prosecution and maintenance related to the licensed patent rights. The Company has further agreed to pay Penn, for the benefit of the Licensors, up to an aggregate of $15.7 million if it achieves specified clinical, marketing approval and reimbursement approval milestones with respect to one licensed product, and up to an aggregate of an additional $3.1 million if it achieves these same milestones with respect to a different licensed product. In addition, it has agreed to pay Penn, for the benefit of the Licensors, up to an aggregate of $48.0 million if it achieves specified commercial sales milestones with respect to one licensed product, and up to an aggregate of an additional $9.6 million if it achieves these same milestones with respect to a different licensed product. The Company is also obligated to pay Penn, for the benefit of the Licensors, royalties at a low single-digit percentage of net sales of licensed products. Such royalties are subject to customary deductions, credits, and reductions for lack of patent coverage and loss of regulatory exclusivity. In addition, such royalties with respect to any licensed product in any country may be offset by a specified portion of any royalty payments actually paid by the Company in such country under third-party licenses to patent rights or other intellectual property rights that are necessary to research, develop, manufacture and commercialize the licensed product in such country. Its obligation to pay royalties under the BEST1 License Agreement will continue on a licensed product-by-licensed product and country-by-country basis until the latest of: •the expiration of the last-to-expire licensed patent rights covering the sale of the applicable licensed product in the country of sale; •the expiration of regulatory exclusivity covering the applicable licensed product in the country of sale; and •10 years from the first commercial sale of the applicable licensed product in the country of sale. Beginning on the earlier of the calendar year following the first commercial sale of a licensed product and calendar year 2032, the Company is also obligated to pay certain minimum royalties, not to exceed an amount in the mid tens of 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 sublicense any of the licensed patent rights to a third party, it will be obligated to pay Penn, for the benefit of the Licensors, a high single-digit to a mid ten's percentage of the consideration received in exchange for such sublicense, with the applicable percentage based upon the stage of development of the sublicensed product 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 the Company subsequently uses such priority review voucher in connection with a different product candidate outside the scope of the BEST1 License Agreement, it will be obligated to pay Penn, for the benefit of the Licensors, aggregate payments in the low double-digit millions of dollars based on certain approval and commercial sales milestones with respect to such other product candidate. In addition, if it sells such a priority review voucher to a third party, it will be obligated to pay Penn, for the benefit of the Licensors, a high single-digit percentage of any consideration received from such third party in connection with such sale. The BEST1 License Agreement, unless earlier terminated by the Company or Penn or UFRF, will expire upon the expiration of the Company's obligation to pay royalties on net sales of licensed products. Before the effectiveness of an IND for a licensed product, the Company may terminate the BEST1 License Agreement with respect to such licensed product or in its entirety, at any time for any reason upon prior written notice to Penn and UFRF. Following the effectiveness of an IND for a licensed product, it may terminate the BEST1 License Agreement with respect to such licensed product by providing Penn prior written notice and a certification that it is ceasing all use, research and development and commercialization of such licensed product, subject to certain limited exceptions. It may also terminate the BEST1 License Agreement if Penn or UFRF materially breaches the BEST1 License Agreement and does not cure such breach within a specified cure period. Penn or UFRF may terminate the BEST1 License Agreement if the Company materially breaches the BEST1 License Agreement and does not cure such breach within a specified cure period, if it experiences a specified insolvency event, if it ceases to carry on the entirety of its business related to the licensed patent rights, if it ceases for more than four consecutive quarters to make any payment of earned royalties on net sales of licensed products following the commencement of commercialization thereof, unless such cessation is based on safety concerns that the Company is actively attempting to address, or if it, any of its affiliates or any of its sublicensees challenges or assists a third party in challenging the validity, scope, patentability, and/or enforceability of the licensed patent rights. If it materially breaches certain diligence obligations under the BEST1 License Agreement with respect to only one licensed product, then Penn and UFRF may only terminate its rights and licenses under the BEST1 License Agreement for such licensed product, but not for other licensed products. 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.

Property and Equipment

12 Months Ended

Dec. 31, 2021

Property, Plant and Equipment [Abstract]

Property and Equipment

Property and equipment as of December 31, 2021 and 2020 were as follows:


	Useful Life (Years)	December 31, 2021		December 31, 2020
Research, manufacturing and clinical equipment	5 - 10	$	283	$	47
Computer, software and other office equipment	5	933		933
Automobile	5	125		—
		1,341		980
Accumulated depreciation		(993)		(954)
Property and equipment, net		$	348	$	26

For the years ended December 31, 2021, 2020 and 2019, depreciation expense was $39 thousand, $143 thousand and $162 thousand, respectively.

Income Taxes

12 Months Ended

Dec. 31, 2021

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,
	2021		2020		2019
Percent of pre-tax income:
U.S. federal statutory income tax rate	21.0	%	21.0	%	21.0	%
State taxes, net of federal benefit	8.1	%	14.8	%	10.9	%
Permanent items	0.7	%	0.2	%	(1.0)	%

Impact of state rate changes	(3.8)	%	0.1	%	0.1	%
Research and development credit	3.3	%	3.1	%	2.8	%

Change in valuation allowance	(29.3)	%	(34.8)	%	(33.6)	%
Effective income tax rate	—	%	4.4	%	0.2	%

The components of income tax benefit are as follows:


	Years ended December 31,
	2021		2020		2019
Current:
Federal	$	—	$	—	$	—
State	—		(3,695)		(111)
Deferred:
Federal	—		—		—
State	—		—		—
Income tax benefit	$	—	$	(3,695)	$	(111)

Significant components of the Company's deferred tax assets (liabilities) for 2021 and 2020 consist of the following:


	As of December 31,
	2021		2020
Deferred tax assets (liabilities)

License and technology payments	$	5,356	$	7,479
Share-based compensation	21,614		23,266
Accrued expenses	320		427
Right-of-use asset	(430)		(40)
Lease obligation	444		38
Depreciation	1		6
Federal and state net operating loss carryforwards	165,401		130,524
Research and development credits	13,742		9,959
Other	20		7
Deferred income tax assets	206,468		171,666
Valuation allowance	(206,468)		(171,666)
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 2021 and 2020. 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. As of December 31, 2021, the Company has federal NOL carryforwards of approximately $562 million.

For the year ended December 31, 2021, the Company recorded no benefit from income taxes. For the years ended December 31, 2020 and 2019, the Company recorded an income tax benefit of $3.7 million and $0.1 million, respectively, due 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, 2021.

Pursuant to ASC 740, 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, 2021, 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 2018 through 2020, and state tax jurisdictions for the years 2017 through 2020. 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 http://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 http://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 http://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 http://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 14
-URI http://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 http://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 http://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 http://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 http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

Operating Leases

12 Months Ended

Dec. 31, 2021

Leases [Abstract]

Operating Leases

The Company's principal executive office was previously at One Penn Plaza, New York, NY. The term of this lease expired in December 2020.

In December 2020, the Company entered into a lease agreement for office space located in Parsippany, New Jersey. The Company recognized a right-to-use asset and lease liability when the term of the lease commenced in April 2021. The term of the lease for the Company's Parsippany office will expire in August 2023.

The Company leases office space located in Cranbury, New Jersey under non-cancelable operating lease arrangements. The lease for the Company's Cranbury office commenced in February 2020 and expires in February 2023.

The Company is party to an office service agreement with Regus Management Group, LLC for use of office space at Five Penn Plaza, New York, NY. This agreement currently expires in May 2022.

For the years ended December 31, 2021, 2020 and 2019, lease and rent expense was $0.7 million, $0.6 million, and $1.0 million, respectively. Cash paid from operating cash flows for amounts included in the measurement of lease liabilities was $0.7 million and $0.6 million for the years ended December 31, 2021 and 2020, respectively. At December 31, 2021, the Company's operating leases had a weighted average remaining lease term of 1.6 years and a weighted average estimated incremental borrowing rate of 3.2% .

The following presents the maturity of the Company's operating lease liabilities as of December 31, 2021:


	December 31, 2021
2022	$	989
2023	627
2024	—

Total minimum lease payments	1,616
Less imputed interest	(45)
Present value of minimum lease payments	1,571
Less current portion	952
Total long-term operating lease liabilities	$	619

Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Zimura - Archemix Corp. The Company is party to an agreement with Archemix Corp., or Archemix, under which the Company in-licensed rights in certain patents, patent applications and other intellectual property related to Zimura and pursuant to which the Company may be required to pay sublicense fees and make milestone payments (the "C5 License Agreement"). For each anti-C5 aptamer product that the Company may develop under the agreement, including Zimura, 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 licensed products. 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. IC-100 - University of Florida Research Foundation and the University of Pennsylvania Under its exclusive license agreement with UFRF and Penn for rights to IC-100, the Company is obligated to make payments to UFRF, for the benefit of the Licensors, of up to an aggregate of $23.5 million if the Company achieves specified clinical, marketing approval and reimbursement approval milestones with respect to a licensed product and up to an aggregate of an additional $70.0 million if the Company achieves specified commercial sales milestones with respect to a licensed product. The Company is also obligated to pay UFRF, for the benefit of the Licensors, a low single-digit percentage of net sales of licensed products. The Company is also obligated to pay UFRF, for the benefit of the Licensors, a double-digit percentage of specified non-royalty payments the Company may receive from any third-party sublicensee of the licensed patent rights. Further, 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 the Company subsequently uses such priority review voucher in connection with a different product candidate, the Company will be obligated to pay UFRF, for the benefit of the Licensors, aggregate payments in the low double-digit millions of dollars based on certain approval and commercial sales milestones with respect to such other product candidate. In addition, if the Company sells such a priority review voucher to a third party, the Company will be obligated to pay UFRF, for the benefit of the Licensors, a low double-digit percentage of any consideration received from such third party in connection with such sale. IC-200 - University of Pennsylvania and the University of Florida Research Foundation Under its exclusive license agreement with Penn and UFRF for rights to IC-200, the Company is obligated to make payments to Penn, for the benefit of the Licensors, of up to an aggregate of $15.7 million if the Company achieves specified clinical, marketing approval and reimbursement approval milestones with respect to one licensed product and up to an aggregate of an additional $3.1 million if the Company achieves these same milestones with respect to a different licensed product. In addition, the Company is obligated to make payments to Penn, for the benefit of the Licensors, of up to an aggregate of $48.0 million if the Company achieves specified commercial sales milestones with respect to one licensed product and up to an aggregate of an additional $9.6 million if the Company achieves these same milestones with respect to a different licensed product. The Company is also obligated to pay Penn, for the benefit of the Licensors, a low single-digit percentage of net sales of licensed products. The Company is also obligated to pay Penn, for the benefit of the Licensors, a high single-digit to a mid-ten's percentage of specified non-royalty payments the Company may receive from any third-party sublicensee of the licensed patent rights, with the applicable percentage based upon the stage of development of the sublicensed product at the time the Company enters into the sublicense. Further, 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 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 Penn, for the benefit of the Licensors, aggregate payments in the low double-digit millions of dollars based on certain approval and commercial sales milestones with respect to such other product candidate. In addition, if the Company sells such a priority review voucher to a third party, the Company will be obligated to pay Penn, for the benefit of the Licensors, a high single-digit percentage of any consideration received from such third party in connection with such sale. miniCEP290 Program - University of Massachusetts Under the miniCEP290 License Agreement, 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 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 a product candidate from its HtrA1 inhibitor program, including IC-500, 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 Inception 4 Merger, 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 Merger, 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. IVERIC bio, Inc., 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. IVERIC bio, Inc., 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, which has been submitted 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, and the Company expects this settlement amount will be fully covered and paid directly to the plaintiffs by its insurance carriers. The Company does not expect this settlement, if approved in its current form, to have a material impact on its 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 October 18, 2021, the parties notified the court overseeing the Pacheco matter that they had reached an agreement in principle to settle the action. . On January 27, 2022, the parties executed a settlement agreement, which has been submitted to the court for approval. 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. The Company has entered into tolling agreements with the directors named in the demands to December 2022. On January 27, 2022, the parties executed a settlement agreement. The Company denies any and all allegations of wrongdoing and intends to vigorously defend against these lawsuits. The Company is unable, however, to predict the outcome of these matters, including that of the settlement agreement discussions, at this time. Moreover, any conclusion of these matters in a manner adverse to the Company and for which it incurs substantial costs or damages not covered by the Company's directors’ and officers’ liability insurance would have a material adverse effect on its financial condition and business. In addition, the litigation could adversely impact the Company's reputation and divert management’s attention and resources from other priorities, including the execution of its business plan and strategies that are important to the Company's ability to grow its business, any of which could have a material adverse effect on the Company's business.

Stock-Based Compensation and Compensation Plans

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

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 15,624,000 additional shares to the 2013 Plan, including for 2022, an increase of approximately 2,542,000 shares. As of December 31, 2021, the Company had approximately 1,168,000 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 and December 2021, the Company's board of directors further amended the 2019 Inducement Plan to reserve an additional 1,000,000 shares of common stock and an additional 1,000,000 shares of common stock, respectively, 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, 2021, the Company had approximately 1,372,000 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.

A summary of the stock option activity, weighted average exercise prices, options outstanding and exercisable as of December 31, 2021, 2020 and 2019 is as follows (in thousands except weighted average exercise price):


	Years ended December 31,
	2021			2020			2019
	Common Stock Options	Weighted Average Exercise Price		Common Stock Options	Weighted Average Exercise Price		Common Stock Options	Weighted Average Exercise Price
Outstanding, December 31, 2020	8,928	$	9.22	6,780	$	10.89	5,903	$	13.72
Granted	3,204	$	13.03	2,630	$	6.10	1,610	$	4.26
Exercised	(646)	$	2.80	(109)	$	2.89	(80)	$	2.66
Expired or forfeited	(625)	$	8.87	(373)	$	19.49	(653)	$	21.16
Outstanding, December 31, 2021	10,861	$	10.94	8,928	$	9.22	6,780	$	10.89


	Years ended December 31,
	2021		2020		2019
Options exercisable at December 31, 2021	5,584		4,462		3,317
Weighted average grant date fair value (per share) of options granted during the period	$	10.53	$	4.83	$	3.37

As of December 31, 2021, there were approximately 10,386,000 options outstanding, net of estimated forfeitures, that had vested or are expected to vest. The weighted-average exercise price of these options was $10.98 per option; the weighted-average remaining contractual life of these options was 7.4 years; and the aggregate intrinsic value of these options was approximately $88.8 million. A summary of the stock options outstanding and exercisable as of December 31, 2021 is as

follows (in thousands except exercise prices and weighted average exercise price):


			December 31, 2021
			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	2,286		6.3	$	2.39	2,081		$	2.49
$2.97-$4.88	1,917		6.9	$	4.07	1,447		$	4.16
$4.89-$8.07	2,749		8.7	$	6.66	801		$	6.35
$8.08-$15.00	2,079		9.3	$	13.38	136		$	10.33
$15.01-$73.22	1,830		5.6	$	32.49	1,119		$	42.69
	10,861		7.4	$	10.94	5,584		$	11.72

Aggregate Intrinsic Value	$	88,821				$	56,986

Cash proceeds from, and the aggregate intrinsic value of, stock options exercised during the years ended December 31, 2021, 2020 and 2019, respectively, were as follows:


	Years ended December 31,
	2021		2020		2019
Cash proceeds from options exercised	$	1,808	$	314	$	192
Aggregate intrinsic value of options exercised	$	4,997	$	393	$	135

In connection with stock option awards granted to employees, non-employees directors and certain other individuals, the Company recognized approximately $6.5 million, $4.7 million and $5.9 million in share-based compensation expense during the years ended December 31, 2021, 2020 and 2019, respectively, net of expected forfeitures. As of December 31, 2021, there were approximately $37.6 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 3.4 years.

The following table presents a summary of the Company's outstanding RSU awards granted as of December 31, 2021 (in thousands except weighted average grant-date fair value)


	Restricted Stock Units	Weighted Average Grant-Date Fair Value
Outstanding, December 31, 2020	1,958	$	6.95
Awarded	1,274	$	13.07
Vested	(711)	$	5.03
Expired or forfeited	(275)	$	17.50
Outstanding, December 31, 2021	2,246	$	9.82

As of December 31, 2021, there were approximately 2,044,000 RSUs outstanding, net of estimated forfeitures, that are expected to vest. The weighted-average fair value of these RSUs was $9.82 per share; and the aggregate intrinsic value of these RSUs was approximately $34.2 million.

In connection with RSUs granted to employees, non-employees directors and certain other individuals, the Company recognized approximately $4.6 million, $3.3 million and $3.0 million in share-based compensation expense during the years ended December 31, 2021, 2020 and 2019, respectively, net of expected forfeitures. As of December 31, 2021, there was approximately $18.8 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 3.2 years. The total fair value of the RSUs that vested during the year ended December 31, 2021 was $3.7 million.

In connection with the ESPP made available to employees, the Company recognized approximately $0.2 million and $0.1 million of share-based compensation expense during the years ended December 31, 2021 and December 31, 2020, respectively, net of expected forfeitures. As of December 31, 2021, there was a de minimis amount of unrecognized compensation costs, net of estimated forfeitures, related to the ESPP, which are expected to be recognized over 0.2 years. There were 51,951 and 76,402 shares of common stock issued under the ESPP during the year ended December 31, 2021 and 2020, respectively. Cash proceeds from ESPP purchases were approximately $0.3 million and $0.1 million during the year ended December 31, 2021 and 2020, respectively. As of December 31, 2021, 753,410 shares were available for future purchases under the ESPP.

Employee Benefit Plan	12 Months Ended
Employee Benefit Plan	Dec. 31, 2021
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 $0.6 million, $0.3 million and $0.2 million during the years ended December 31, 2021, 2020 and 2019, respectively.

- Definition

The entire disclosure for retirement benefits.

+ References

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+ Details

Summary of Significant Accounting Policies (Policies)	12 Months Ended
Summary of Significant Accounting Policies (Policies)	Dec. 31, 2021
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 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, 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 Zimura 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 Zimura. The Company has engaged one additional third-party manufacturer to provide drug substance for Zimura and one additional third-party manufacturer to provide fill/finish services for clinical supplies of Zimura. 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 Zimura. 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 Zimura. The Company currently relies exclusively upon a single third-party contract manufacturer for IC-100 and IC-200, and also relies on sole-source suppliers for certain starting materials used in the manufacture of such product candidates. 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 COVID-19 pandemic, 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.
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.
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. 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.
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 academic research collaborators, 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.
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.
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. 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 and Recent 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.

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2021

Accounting Policies [Abstract]

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


	Years ended December 31,
	2021	2020	2019
Expected common stock price volatility	114%	118%	110%
Risk-free interest rate	0.31%-1.22%	0.22%-1.34%	1.38%-2.54%
Expected term of options (years)	5.2	4.6	4.8
Expected dividend yield	—	—	—

Schedule of Share-based Compensation Expense


	Years ended December 31,
	2021		2020		2019
Research and development	$	6,522	$	4,166	$	4,260
General and administrative	4,723		4,157		4,920
Total	$	11,245	$	8,323	$	9,180

Net Income (Loss) Per Common Share (Tables)

12 Months Ended

Dec. 31, 2021

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,
	2021		2020		2019
Basic and diluted net income (loss) per common share calculation:
Net loss	$	(114,522)	$	(84,547)	$	(58,859)


Weighted average common shares outstanding - dilutive	101,866		74,185		42,224
Net loss per common share - basic and diluted	$	(1.12)	$	(1.14)	$	(1.39)

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


	Years ended December 31,
	2021	2020	2019
Stock options outstanding	10,861	8,928	6,780
Restricted stock units	2,246	1,958	1,481
Total	13,107	10,886	8,261

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

12 Months Ended

Dec. 31, 2021

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, 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


	As of As of December 31, 2020
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
U.S. Treasury securities	$	54,225	$	8	—		$	54,233
Corporate debt securities	79,282		4		(10)		79,276
Asset-backed securities	10,164		1		—		10,165

Total	$	143,671	$	13	$	(10)	$	143,674

Fair Value Measurements - (Tables)

12 Months Ended

Dec. 31, 2021

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*	$	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	$	—


	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*	$	58,042	$	—	$	—
Investments in U.S. Treasury securities	$	54,233	$	—	$	—
Investments in corporate debt securities	$	—	$	79,275	$	—
Investments in asset-backed securities	$	—	$	10,166	$	—

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

Property and Equipment (Tables)

12 Months Ended

Dec. 31, 2021

Property, Plant and Equipment [Abstract]

Schedule of Property and Equipment

Property and equipment as of December 31, 2021 and 2020 were as follows:


	Useful Life (Years)	December 31, 2021		December 31, 2020
Research, manufacturing and clinical equipment	5 - 10	$	283	$	47
Computer, software and other office equipment	5	933		933
Automobile	5	125		—
		1,341		980
Accumulated depreciation		(993)		(954)
Property and equipment, net		$	348	$	26

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2021

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,
	2021		2020		2019
Percent of pre-tax income:
U.S. federal statutory income tax rate	21.0	%	21.0	%	21.0	%
State taxes, net of federal benefit	8.1	%	14.8	%	10.9	%
Permanent items	0.7	%	0.2	%	(1.0)	%

Impact of state rate changes	(3.8)	%	0.1	%	0.1	%
Research and development credit	3.3	%	3.1	%	2.8	%

Change in valuation allowance	(29.3)	%	(34.8)	%	(33.6)	%
Effective income tax rate	—	%	4.4	%	0.2	%

Schedule of Components of Income Tax (Benefit) Expense

The components of income tax benefit are as follows:


	Years ended December 31,
	2021		2020		2019
Current:
Federal	$	—	$	—	$	—
State	—		(3,695)		(111)
Deferred:
Federal	—		—		—
State	—		—		—
Income tax benefit	$	—	$	(3,695)	$	(111)

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

Significant components of the Company's deferred tax assets (liabilities) for 2021 and 2020 consist of the following:


	As of December 31,
	2021		2020
Deferred tax assets (liabilities)

License and technology payments	$	5,356	$	7,479
Share-based compensation	21,614		23,266
Accrued expenses	320		427
Right-of-use asset	(430)		(40)
Lease obligation	444		38
Depreciation	1		6
Federal and state net operating loss carryforwards	165,401		130,524
Research and development credits	13,742		9,959
Other	20		7
Deferred income tax assets	206,468		171,666
Valuation allowance	(206,468)		(171,666)
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

Operating Leases (Tables)

12 Months Ended

Dec. 31, 2021

Leases [Abstract]

Schedule of Operating Lease Liability Maturities

The following presents the maturity of the Company's operating lease liabilities as of December 31, 2021:


	December 31, 2021
2022	$	989
2023	627
2024	—

Total minimum lease payments	1,616
Less imputed interest	(45)
Present value of minimum lease payments	1,571
Less current portion	952
Total long-term operating lease liabilities	$	619

Stock-Based Compensation and Compensation Plans (Tables)

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

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


	Years ended December 31,
	2021			2020			2019
	Common Stock Options	Weighted Average Exercise Price		Common Stock Options	Weighted Average Exercise Price		Common Stock Options	Weighted Average Exercise Price
Outstanding, December 31, 2020	8,928	$	9.22	6,780	$	10.89	5,903	$	13.72
Granted	3,204	$	13.03	2,630	$	6.10	1,610	$	4.26
Exercised	(646)	$	2.80	(109)	$	2.89	(80)	$	2.66
Expired or forfeited	(625)	$	8.87	(373)	$	19.49	(653)	$	21.16
Outstanding, December 31, 2021	10,861	$	10.94	8,928	$	9.22	6,780	$	10.89


	Years ended December 31,
	2021		2020		2019
Options exercisable at December 31, 2021	5,584		4,462		3,317
Weighted average grant date fair value (per share) of options granted during the period	$	10.53	$	4.83	$	3.37

Summary of the Stock Options Outstanding and Exercisable

A summary of the stock options outstanding and exercisable as of December 31, 2021 is as

follows (in thousands except exercise prices and weighted average exercise price):


			December 31, 2021
			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	2,286		6.3	$	2.39	2,081		$	2.49
$2.97-$4.88	1,917		6.9	$	4.07	1,447		$	4.16
$4.89-$8.07	2,749		8.7	$	6.66	801		$	6.35
$8.08-$15.00	2,079		9.3	$	13.38	136		$	10.33
$15.01-$73.22	1,830		5.6	$	32.49	1,119		$	42.69
	10,861		7.4	$	10.94	5,584		$	11.72

Aggregate Intrinsic Value	$	88,821				$	56,986

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, 2021, 2020 and 2019, respectively, were as follows:


	Years ended December 31,
	2021		2020		2019
Cash proceeds from options exercised	$	1,808	$	314	$	192
Aggregate intrinsic value of options exercised	$	4,997	$	393	$	135

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, 2021 (in thousands except weighted average grant-date fair value)


	Restricted Stock Units	Weighted Average Grant-Date Fair Value
Outstanding, December 31, 2020	1,958	$	6.95
Awarded	1,274	$	13.07
Vested	(711)	$	5.03
Expired or forfeited	(275)	$	17.50
Outstanding, December 31, 2021	2,246	$	9.82

Business (Details)	Dec. 31, 2021 segment
Adeno-Associated Virus Mediated Gene Therapy Program
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of product candidates in preclinical development	2

Summary of Significant Accounting Policies - Segment and Geographic Information (Details)	12 Months Ended
	Dec. 31, 2021 segment
Accounting Policies [Abstract]
Number of operating segments	1
Number of reporting segments	1

Summary of Significant Accounting Policies - Cash and Cash Equivalents (Details) $ in Millions	Dec. 31, 2021 USD ($)
Accounting Policies [Abstract]
Cash, cash equivalents and available for sale securities	$ 381.7

Summary of Significant Accounting Policies - Property and Equipment (Details)	12 Months Ended
	Dec. 31, 2021
Minimum
Property and equipment
Estimated useful lives	3 years
Maximum
Property and equipment
Estimated useful lives	10 years

Summary of Significant Accounting Policies - Share-Based Compensation (Details) - shares	1 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2021	Apr. 30, 2016
Share-Based Compensation
Expected dividend yield		0.00%
ESPP
Share-Based Compensation
Withholding period	6 months
ESPP \| Maximum
Share-Based Compensation
Number of shares reserved for issuance under the Plan (in shares)			1,000,000

Summary of Significant Accounting Policies - Schedule of Weighted-Average Assumptions (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate, minimum	0.31%	0.22%	1.38%
Risk-free interest rate, maximum	1.22%	1.34%	2.54%
Expected dividend yield	0.00%
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected common stock price volatility	114.00%	118.00%	110.00%
Expected term of options (years)	5 years 2 months 12 days	4 years 7 months 6 days	4 years 9 months 18 days
Expected dividend yield	0.00%	0.00%	0.00%

Summary of Significant Accounting Policies - Schedule of Share-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-Based Compensation
Share-based compensation expense	$ 11,245	$ 8,323	$ 9,180
Research and development
Share-Based Compensation
Share-based compensation expense	6,522	4,166	4,260
General and administrative
Share-Based Compensation
Share-based compensation expense	$ 4,723	$ 4,157	$ 4,920

Common Stock - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended			12 Months Ended
	Oct. 31, 2021	Jul. 31, 2021	Jun. 30, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Jul. 30, 2021
Class of Stock [Line Items]
Payments of stock issuance costs	$ 10,800	$ 7,400	$ 10,100
Proceeds from issuance of common stock and pre-funded warrants, net, and related to acquisition	$ 162,600		$ 150,100
Number of warrants issued (in shares)			1,914,280
Underwritten Offering
Class of Stock [Line Items]
Sale of stock, number of shares issued in transaction (in shares)			28,503,220
Sale of stock, price per share (in dollars per share)			$ 4.10
Underwritten Offering, Underwriters
Class of Stock [Line Items]
Sale of stock, price per share (in dollars per share)			$ 3.854
Private Placement
Class of Stock [Line Items]
Sale of stock, number of shares issued in transaction (in shares)			8,649,453
Sale of stock, price per share (in dollars per share)			$ 4.10
Proceeds from issuance of common stock and pre-funded warrants, net, and related to acquisition				$ 0	$ 33,237	$ 0
Warrant price (USD per share)			4.099
Private Placement, Underwriters
Class of Stock [Line Items]
Warrant price (USD per share)			$ 3.853
Public Stock Offering
Class of Stock [Line Items]
Sale of stock, number of shares issued in transaction (in shares)	10,350,000	13,397,500
Sale of stock, price per share (in dollars per share)	$ 16.75						$ 8.60
Proceeds from issuance of common stock and pre-funded warrants, net, and related to acquisition		$ 107,800		$ 270,319	$ 116,883	$ 42,565
Over-Allotment Option
Class of Stock [Line Items]
Sale of stock, number of shares issued in transaction (in shares)	1,350,000	1,747,500
Sale of stock, price per share (in dollars per share)	$ 15.745						$ 8.084

Net Income (Loss) Per Common Share - Narrative (Details) - shares	Dec. 31, 2021	Dec. 31, 2020
Earnings Per Share [Abstract]
Pre-funded warrants outstanding (in shares)	3,164,280	3,164,280

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, 2021	Dec. 31, 2020	Dec. 31, 2019
Basic and diluted net loss per common share calculation:
Net loss	$ (114,522)	$ (84,547)	$ (58,859)
Weighted average common shares outstanding - dilutive	101,866	74,185	42,224
Net income (loss) per common share - basic (in dollars per share)	$ (1.12)	$ (1.14)	$ (1.39)
Net income (loss) per common share - diluted (in dollars per share)	$ (1.12)	$ (1.14)	$ (1.39)

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 40
-Section 65
-Paragraph 1
-Subparagraph (e)(4)
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=125511455&loc=d3e1448-109256

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22595-107794

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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-Subparagraph (a)
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=125511455&loc=d3e1337-109256

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 40
-Section 65
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=123482062&loc=SL123482106-238011

Reference 9: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 55
-Paragraph 52
-URI http://asc.fasb.org/extlink&oid=125512782&loc=d3e4984-109258

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(23))
-URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

- Definition

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.

+ References

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+ Details

- Definition

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

+ References

+ Details

Net Income (Loss) Per Common Share - Schedule of Potentially Dilutive Securities (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	13,107	10,886	8,261
Stock options outstanding
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	10,861	8,928	6,780
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	2,246	1,958	1,481

Cash, Cash Equivalents and Available for Sale Securities - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Cash and Cash Equivalents [Abstract]
Cash and cash equivalents	$ 261,447	$ 66,373
Cash	9,900	8,400
Cash equivalents	251,500	58,000
Available for sale debt securities	$ 120,302	$ 143,674

Cash, Cash Equivalents and Available for Sale Securities - Schedule of Available for Sale Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 120,392	$ 143,671
Gross Unrealized Gains	0	13
Gross Unrealized Losses	(90)	(10)
Fair Value	120,302	143,674
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	18,202	54,225
Gross Unrealized Gains	0	8
Gross Unrealized Losses	(16)	0
Fair Value	18,185	54,233
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	82,138	79,282
Gross Unrealized Gains	0	4
Gross Unrealized Losses	(57)	(10)
Fair Value	82,081	79,276
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	16,008	10,164
Gross Unrealized Gains	0	1
Gross Unrealized Losses	(14)	0
Fair Value	15,995	$ 10,165
Supranational securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	4,044
Gross Unrealized Gains	0
Gross Unrealized Losses	(3)
Fair Value	$ 4,041

Fair Value Measurements - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Fair Value Measurements
Transfer of assets from Level 1 to Level 2 of the fair value measurement hierarchy	$ 0	$ 0
Recurring basis \| Quoted prices in active markets for identical assets (Level 1) \| Money market funds
Fair Value Measurements
Investments in money market funds	251,488,000	58,042,000
Recurring basis \| Quoted prices in active markets for identical assets (Level 1) \| U.S. Treasury securities
Fair Value Measurements
Investments in money market funds	18,185,000	54,233,000
Recurring basis \| Quoted prices in active markets for identical assets (Level 1) \| Corporate debt securities
Fair Value Measurements
Investments in money market funds	0	0
Recurring basis \| Quoted prices in active markets for identical assets (Level 1) \| Asset-backed securities
Fair Value Measurements
Investments in money market funds	0	0
Recurring basis \| Quoted prices in active markets for identical assets (Level 1) \| Supranational securities
Fair Value Measurements
Investments in money market funds	0
Recurring basis \| Significant other observable inputs (Level 2) \| Money market funds
Fair Value Measurements
Investments in money market funds	0	0
Recurring basis \| Significant other observable inputs (Level 2) \| U.S. Treasury securities
Fair Value Measurements
Investments in money market funds	0	0
Recurring basis \| Significant other observable inputs (Level 2) \| Corporate debt securities
Fair Value Measurements
Investments in money market funds	82,081,000	79,275,000
Recurring basis \| Significant other observable inputs (Level 2) \| Asset-backed securities
Fair Value Measurements
Investments in money market funds	15,995,000	10,166,000
Recurring basis \| Significant other observable inputs (Level 2) \| Supranational securities
Fair Value Measurements
Investments in money market funds	4,041,000
Recurring basis \| Significant unobservable inputs (Level 3) \| Money market funds
Fair Value Measurements
Investments in money market funds	0	0
Recurring basis \| Significant unobservable inputs (Level 3) \| U.S. Treasury securities
Fair Value Measurements
Investments in money market funds	0	0
Recurring basis \| Significant unobservable inputs (Level 3) \| Corporate debt securities
Fair Value Measurements
Investments in money market funds	0	0
Recurring basis \| Significant unobservable inputs (Level 3) \| Asset-backed securities
Fair Value Measurements
Investments in money market funds	0	$ 0
Recurring basis \| Significant unobservable inputs (Level 3) \| Supranational securities
Fair Value Measurements
Investments in money market funds	$ 0

Licensing and Commercialization Agreements - Zimura License Agreement With Archemix Corp. (Details) - Archemix - C5 Licensed Product - License Agreements $ in Millions	1 Months Ended			8 Months Ended	12 Months Ended	110 Months Ended
	Oct. 31, 2020 USD ($)	Mar. 31, 2020 USD ($)	Sep. 30, 2011 USD ($) shares	Oct. 31, 2020 milestone_payment_number	Dec. 31, 2020	Oct. 31, 2020 USD ($)
Agreement
Licensing agreement term			12 years
Achievement of specified clinical and regulatory milestones
Agreement
Payments for license fees	$ 6.0	$ 1.0	$ 1.0			$ 9.0
Number of milestone payments \| milestone_payment_number				2
Trial data period					12 months
Achievement of specified clinical and regulatory milestones \| Maximum
Agreement
Amount to be paid on achievement of milestone			$ 50.5
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			$ 24.5
First indication \| Maximum
Agreement
Amount to be paid on achievement of milestone			24.5
Second and third indication
Agreement
Amount to be paid on achievement of milestone			23.5
Second and third indication \| Maximum
Agreement
Amount to be paid on achievement of milestone			23.5
Sustained delivery applications
Agreement
Amount to be paid on achievement of milestone			2.5
Sustained delivery applications \| Maximum
Agreement
Amount to be paid on achievement of milestone			2.5
Achievement of specified commercial milestones \| Maximum
Agreement
Amount to be paid on achievement of milestone			$ 22.5

Licensing and Commercialization Agreements - RHO-adRP License Agreement with the University of Florida Research Foundation and the University if Pennsylvania (Details) - University of Florida Research Foundation (UFRF) - RHO-adRP License Agreement $ in Millions	1 Months Ended
	Jun. 30, 2018 USD ($)
Agreement
Licensing agreement term	10 years
Research and development \| Specified Clinical, Marketing Approval and Reimbursement Approval Milestones Related to a Licensed Product
Agreement
Payments for license fees	$ 23.5
Research and development \| Specified Commercial Sales Milestones Related to a Licensed Product
Agreement
Payments for license fees	$ 70.0

Licensing and Commercialization Agreements - BEST1 License Agreement with University of Pennsylvania and University of Florida Research Foundation (Details) $ in Thousands	1 Months Ended
	May 31, 2019 USD ($) licensedProduct
Agreement
Number of licensed products \| licensedProduct	1
University Of Florida Research Foundation (UFRF) And University Of Pennsylvania (Penn) \| BEST1 License Agreement
Agreement
Licensing agreement term	10 years
Specified Clinical, Marketing Approval and Reimbursement Approval Milestones Related to a Licensed Product \| University Of Pennsylvania \| Primary Licensed Product \| Research and development \| BEST1 License Agreement
Agreement
Payments for license fees	$ 200
Specified Clinical, Marketing Approval and Reimbursement Approval Milestones Related to a Licensed Product \| University of Florida Research Foundation (UFRF) \| Primary Licensed Product \| General and administrative \| BEST1 License Agreement
Agreement
Payments for license fees	18
Specified Clinical, Marketing Approval and Reimbursement Approval Milestones Related to a Licensed Product \| University Of Florida Research Foundation (UFRF) And University Of Pennsylvania (Penn) \| Primary Licensed Product \| Research and development \| BEST1 License Agreement
Agreement
Payments for license fees	15,700
Specified Clinical, Marketing Approval and Reimbursement Approval Milestones Related to a Licensed Product \| University Of Florida Research Foundation (UFRF) And University Of Pennsylvania (Penn) \| Other Licensed Product \| Research and development \| BEST1 License Agreement
Agreement
Payments for license fees	3,100
Specified Commercial Sales Milestones Related to a Licensed Product \| University Of Florida Research Foundation (UFRF) And University Of Pennsylvania (Penn) \| Primary Licensed Product \| Research and development \| BEST1 License Agreement
Agreement
Payments for license fees	48,000
Specified Commercial Sales Milestones Related to a Licensed Product \| University Of Florida Research Foundation (UFRF) And University Of Pennsylvania (Penn) \| Other Licensed Product \| Research and development \| BEST1 License Agreement
Agreement
Payments for license fees	$ 9,600

Licensing and Commercialization Agreements - License Agreement with University of Massachusetts for the miniCEP290 Program (Details) - University Of Massachusetts (UMass) - miniCEP290 - License Agreements - USD ($) $ in Thousands	1 Months Ended
	Sep. 30, 2019	Jul. 31, 2019	May 31, 2019
Agreement
Shares issued for license fees (in shares)		75,000
Licensing agreement term		10 years
Research and development
Agreement
Payments for license fees	$ 400
Research and development \| Achievement of specified clinical and regulatory milestones
Agreement
Shares issued for license fees (in shares)		75,000	75,000
Payments for license fees		$ 14,750	$ 14,750
Research and development \| Specified Commercial Sales Milestones Related to a Licensed Product
Agreement
Payments for license fees		$ 48,000	$ 48,000
General and administrative
Agreement
Payments for license fees	$ 18

Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Property and Equipment
Property and equipment, gross	$ 1,341	$ 980
Accumulated depreciation	(993)	(954)
Property and equipment, net	348	26
Depreciation expense	$ 39	143	$ 162
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	$ 283	47
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	$ 933	933
Automobile
Property and Equipment
Useful life	5 years
Property and equipment, gross	$ 125	$ 0

Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Percent of pre-tax income:
U.S. federal statutory income tax rate	21.00%	21.00%	21.00%
State taxes, net of federal benefit	8.10%	14.80%	10.90%
Permanent items	0.70%	0.20%	(1.00%)
Impact of state rate changes	(3.80%)	0.10%	0.10%
Research and development credit	3.30%	3.10%	2.80%
Change in valuation allowance	(29.30%)	(34.80%)	(33.60%)
Effective income tax rate	0.00%	4.40%	0.20%

Income Taxes - Schedule of Components of Income Tax (Benefit) Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Current:
Federal	$ 0	$ 0	$ 0
State	0	(3,695)	(111)
Deferred:
Federal	0	0	0
State	0	0	0
Income tax benefit	$ 0	$ (3,695)	$ (111)

- Definition

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

+ References + Details

Income Taxes - Schedule of Significant Components of Deferred Tax Assets (Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets (liabilities)
License and technology payments	$ 5,356	$ 7,479
Share-based compensation	21,614	23,266
Accrued expenses	320	427
Right-of-use asset	(430)	(40)
Lease obligation	444	38
Depreciation	1	6
Federal and state net operating loss carryforwards	165,401	130,524
Research and development credits	13,742	9,959
Other	20	7
Deferred income tax assets	206,468	171,666
Valuation allowance	(206,468)	(171,666)
Net deferred tax assets	$ 0	$ 0

Income Taxes - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
Income Taxes - Narrative (Details) - USD ($) $ in Thousands	Apr. 30, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating Loss Carryforwards [Line Items]
Income tax benefit		$ 0	$ 3,695	$ 111
Change in unrecognized tax liability		0
CARES Act
Operating Loss Carryforwards [Line Items]
Proceeds from income tax refunds	$ 1,800
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Federal net operating loss carryforwards		$ 562,000

- Definition

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

+ References + Details

Income Taxes - Schedule of Position with Respect to Uncertain Tax Positions (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 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

Operating Leases - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating lease rent expense	$ 700	$ 600	$ 1,000
Cash paid from operating cash flows	$ 700	$ 600
Operating lease, weighted average remaining lease term	1 year 7 months 6 days
Weighted average estimated incremental borrowing rate	3.20%

Operating Leases - Schedule of Operating Lease Liability Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Future minimum rental commitments under non-cancelable operating leases
2022	$ 989
2023	627
2024	0
Total minimum lease payments	1,616
Less imputed interest	(45)
Present value of minimum lease payments	1,571
Less current portion	952	$ 54
Total long-term operating lease liabilities	$ 619	$ 61

Commitments and Contingencies - Zimura - Archemix Corp. (Details) - Archemix - C5 Licensed Product - License Agreements $ in Millions	Sep. 30, 2011 USD ($)
Achievement of specified clinical and regulatory milestones \| Maximum
Schedule of Commitments and Contingencies [Line Items]
Amount to be paid on achievement of milestone	$ 50.5
First indication
Schedule of Commitments and Contingencies [Line Items]
Amount to be paid on achievement of milestone	24.5
First indication \| Maximum
Schedule of Commitments and Contingencies [Line Items]
Amount to be paid on achievement of milestone	24.5
Second and third indication
Schedule of Commitments and Contingencies [Line Items]
Amount to be paid on achievement of milestone	23.5
Second and third indication \| Maximum
Schedule of Commitments and Contingencies [Line Items]
Amount to be paid on achievement of milestone	23.5
Sustained delivery applications
Schedule of Commitments and Contingencies [Line Items]
Amount to be paid on achievement of milestone	2.5
Sustained delivery applications \| Maximum
Schedule of Commitments and Contingencies [Line Items]
Amount to be paid on achievement of milestone	2.5
Achievement of specified commercial milestones \| Maximum
Schedule of Commitments and Contingencies [Line Items]
Amount to be paid on achievement of milestone	$ 22.5

Commitments and Contingencies - IC-100 - University of Florida Research Foundation and the University of Pennsylvania (Details) - University of Florida Research Foundation (UFRF) - RHO-adRP License Agreement $ in Millions	Dec. 31, 2018 USD ($)
Specified Clinical, Marketing Approval and Reimbursement Approval Milestones Related to a Licensed Product
Schedule of Commitments and Contingencies [Line Items]
Amount to be paid on achievement of milestone	$ 23.5
Specified Commercial Sales Milestones Related to a Licensed Product
Schedule of Commitments and Contingencies [Line Items]
Amount to be paid on achievement of milestone	$ 70.0

Commitments and Contingencies - IC-200 - University of Pennsylvania and the University of Florida Research Foundation (Details) $ in Millions	1 Months Ended
	May 31, 2019 USD ($) licensedProduct
Schedule of Commitments and Contingencies [Line Items]
Number of licensed products \| licensedProduct	1
Specified Clinical, Marketing Approval and Reimbursement Approval Milestones Related to a Licensed Product \| University Of Florida Research Foundation (UFRF) And University Of Pennsylvania (Penn) \| Primary Licensed Product \| Research and development \| BEST1 License Agreement
Schedule of Commitments and Contingencies [Line Items]
Payments for license fees	$ 15.7
Specified Clinical, Marketing Approval and Reimbursement Approval Milestones Related to a Licensed Product \| University Of Florida Research Foundation (UFRF) And University Of Pennsylvania (Penn) \| Other Licensed Product \| Research and development \| BEST1 License Agreement
Schedule of Commitments and Contingencies [Line Items]
Payments for license fees	3.1
Specified Commercial Sales Milestones Related to a Licensed Product \| University Of Florida Research Foundation (UFRF) And University Of Pennsylvania (Penn) \| Primary Licensed Product \| Research and development \| BEST1 License Agreement
Schedule of Commitments and Contingencies [Line Items]
Payments for license fees	48.0
Specified Commercial Sales Milestones Related to a Licensed Product \| University Of Florida Research Foundation (UFRF) And University Of Pennsylvania (Penn) \| Other Licensed Product \| Research and development \| BEST1 License Agreement
Schedule of Commitments and Contingencies [Line Items]
Payments for license fees	$ 9.6

Commitments and Contingencies - miniCEP290 Program - University of Massachusetts (Details) - University Of Massachusetts (UMass) - miniCEP290 - License Agreements - USD ($) $ in Thousands	1 Months Ended
	Sep. 30, 2019	Jul. 31, 2019	May 31, 2019
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
Achievement of specified clinical and regulatory milestones \| Research and development
Schedule of Commitments and Contingencies [Line Items]
Payments for license fees		$ 14,750	$ 14,750
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	$ 48,000

Commitments and Contingencies - IC_500 - Former Equityholders of Inception 4 (Details) - Inception 4 - USD ($) shares in Millions, $ in Millions		1 Months Ended
	Oct. 30, 2018	Oct. 31, 2018
Schedule of Commitments and Contingencies [Line Items]
Contingent consideration	$ 105
Share price calculation base, period (in days)	5 days
Contingently issuable shares, asset acquisition (in 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
Wet AMD
Schedule of Commitments and Contingencies [Line Items]
Clinical and marketing approval milestones		$ 60

Commitments and Contingencies - Legal Proceedings (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

Stock-Based Compensation and Compensation Plans - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended							2 Months Ended	12 Months Ended			98 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Feb. 28, 2021	Mar. 31, 2020	Jun. 30, 2016	Apr. 30, 2016	Aug. 31, 2013	Feb. 24, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Feb. 24, 2022	Oct. 31, 2019
Stock Option and Compensation Plans
Options outstanding (in shares)	10,386,000								10,386,000
Weighted-average exercise price of options (in dollars per share)	$ 10.98								$ 10.98
Weighted-average remaining contractual life of options									7 years 4 months 24 days
Options, vested and expected to vest, outstanding, aggregate intrinsic value	$ 88,800								$ 88,800
Share-based compensation expense									11,245	$ 8,323	$ 9,180
Stock options
Stock Option and Compensation Plans
Unrecognized share-based compensation costs for option awards, net of estimated forfeitures	$ 37,600								$ 37,600
Expected weighted average period to recognize share-based compensation costs									3 years 4 months 24 days
ESPP
Stock Option and Compensation Plans
Number of shares of common stock available for issuance under the Plan (in shares)	753,410								753,410
Purchase price of common stock as percentage of fair market value						85.00%
Offering period					6 months
Share-based compensation expense									$ 200	$ 100
Expected weighted average period to recognize share-based compensation costs									2 months 12 days
Common stock issued (in shares)									51,951	76,402
Proceeds from stock plans									$ 300	$ 100
Restricted stock units
Stock Option and Compensation Plans
Share-based compensation expense										0
RSUs expected to vest (in shares)	2,044,000								2,044,000
Weighted-average fair value of RSUs expected to vest (in dollars per share)	$ 9.82								$ 9.82
Aggregate intrinsic value of RSUs expected to vest	$ 34,200								$ 34,200
Total fair value vested									3,700
Employees \| Stock options
Stock Option and Compensation Plans
Share-based compensation expense									6,500	4,700	5,900
Employees \| Restricted stock units
Stock Option and Compensation Plans
Share-based compensation expense									$ 4,600	$ 3,300	$ 3,000
Expected weighted average period to recognize share-based compensation costs									3 years 2 months 12 days
Unrecognized compensation costs, net of estimated forfeitures	$ 18,800								$ 18,800
Maximum \| ESPP
Stock Option and Compensation Plans
Number of shares reserved for issuance under the Plan (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)	1,168,000								1,168,000
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%
2013 Plan \| Subsequent Event
Stock Option and Compensation Plans
Increase in number of shares available under the Plan (in shares)								2,542,000				15,624,000
2013 Plan \| Maximum
Stock Option and Compensation Plans
Number of shares reserved for issuance under the Plan (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 (in shares)													1,000,000
Number of shares of common stock available for issuance under the Plan (in shares)	1,372,000								1,372,000
Increase in number of shares available under the Plan (in shares)	1,000,000	1,000,000	600,000	1,000,000

Stock-Based Compensation and Compensation Plans - Summary of Stock Option Activity (Details) - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Common Stock Options
Outstanding at beginning of year (in shares)	8,928	6,780	5,903
Granted (in shares)	3,204	2,630	1,610
Exercised (in shares)	(646)	(109)	(80)
Expired or forfeited (in shares)	(625)	(373)	(653)
Outstanding at end of year (in shares)	10,861	8,928	6,780
Weighted Average Exercise Price
Outstanding at beginning of year (in dollars per share)	$ 9.22	$ 10.89	$ 13.72
Granted (in dollars per share)	13.03	6.10	4.26
Exercised (in dollars per share)	2.80	2.89	2.66
Expired or forfeited (in dollars per share)	8.87	19.49	21.16
Outstanding at end of year (in dollars per share)	$ 10.94	$ 9.22	$ 10.89
Options exercisable at end of year (in shares)	5,584	4,462	3,317
Weighted average grant date fair value (per share) of options granted during the period (in dollars per share)	$ 10.53	$ 4.83	$ 3.37

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, 2021 USD ($) $ / shares shares
Options Outstanding
Total Options Outstanding (in shares) \| shares	10,861
Weighted Average Remaining Life (Years)	7 years 4 months 24 days
Weighted Average Exercise Price (in dollars per share)	$ 10.94
Aggregate Intrinsic Value of Options Outstanding \| $	$ 88,821
Options Exercisable
Number Exercisable (in shares) \| shares	5,584
Weighted Average Exercise Price (in dollars per share)	$ 11.72
Aggregate Intrinsic Value of Options Exercisable \| $	$ 56,986
$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	2,286
Weighted Average Remaining Life (Years)	6 years 3 months 18 days
Weighted Average Exercise Price (in dollars per share)	$ 2.39
Options Exercisable
Number Exercisable (in shares) \| shares	2,081
Weighted Average Exercise Price (in dollars per share)	$ 2.49
$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	1,917
Weighted Average Remaining Life (Years)	6 years 10 months 24 days
Weighted Average Exercise Price (in dollars per share)	$ 4.07
Options Exercisable
Number Exercisable (in shares) \| shares	1,447
Weighted Average Exercise Price (in dollars per share)	$ 4.16
$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	2,749
Weighted Average Remaining Life (Years)	8 years 8 months 12 days
Weighted Average Exercise Price (in dollars per share)	$ 6.66
Options Exercisable
Number Exercisable (in shares) \| shares	801
Weighted Average Exercise Price (in dollars per share)	$ 6.35
$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	2,079
Weighted Average Remaining Life (Years)	9 years 3 months 18 days
Weighted Average Exercise Price (in dollars per share)	$ 13.38
Options Exercisable
Number Exercisable (in shares) \| shares	136
Weighted Average Exercise Price (in dollars per share)	$ 10.33
$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	1,830
Weighted Average Remaining Life (Years)	5 years 7 months 6 days
Weighted Average Exercise Price (in dollars per share)	$ 32.49
Options Exercisable
Number Exercisable (in shares) \| shares	1,119
Weighted Average Exercise Price (in dollars per share)	$ 42.69

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, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Payment Arrangement [Abstract]
Cash proceeds from options exercised	$ 1,808	$ 314	$ 192
Aggregate intrinsic value of options exercised	$ 4,997	$ 393	$ 135

Stock-Based Compensation and Compensation Plans - Summary of Outstanding RSU Awards Granted (Details) - Restricted stock units shares in Thousands	12 Months Ended
	Dec. 31, 2021 $ / shares shares
Restricted Stock Units
Outstanding, beginning of period (in shares) \| shares	1,958
Awarded (in shares) \| shares	1,274
Vested (in shares) \| shares	(711)
Expired or forfeited (in shares) \| shares	(275)
Outstanding, end of period (in shares) \| shares	2,246
Weighted Average Grant-Date Fair Value
Outstanding, beginning of period (in dollars per share) \| $ / shares	$ 6.95
Awarded (in dollars per share) \| $ / shares	13.07
Vested (in dollars per share) \| $ / shares	5.03
Expired or forfeited (in dollars per share) \| $ / shares	17.50
Outstanding, end of period (in dollars per share) \| $ / shares	$ 9.82

Employee Benefit Plan (Details) - USD ($) $ in Millions	12 Months Ended
Employee Benefit Plan (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Retirement Benefits [Abstract]
Defined contribution plan, cost recognized	$ 0.6	$ 0.3	$ 0.2