0001140361-20-005056 | 10-K | XBRL Viewer | Rocket Pharmaceuticals INC

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
Document and Entity Information - USD ($) $ in Millions	Dec. 31, 2019	Mar. 02, 2020	Jun. 28, 2019
Cover [Abstract]
Entity Registrant Name	ROCKET PHARMACEUTICALS, INC.
Entity Central Index Key	0001281895
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	true
Entity Public Float			$ 462.5
Entity Common Stock, Shares Outstanding		55,071,194
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Entity Address, State or Province	NY

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 185,383	$ 111,355
Investments	118,732	94,375
Prepaid expenses and other assets	3,639	3,358
Total current assets	307,754	209,088
Property and equipment, net	29,295	2,027
Goodwill	30,815	30,815
Internal use software	226	0
Restricted cash	1,525	1,436
Deposits	455	545
Operating lease right-of-use assets	2,051	0
Investments	0	7,402
Total assets	372,121	251,313
Current liabilities:
Accounts payable and accrued expenses	17,352	15,372
Operating lease liabilities, current	957	0
Total current liabilities	18,309	15,372
Convertible notes, net of unamortized discount	45,049	41,447
Operating lease liabilities, non-current	1,443	0
Other liabilities	23	457
Total liabilities	64,824	57,276
Commitments and contingencies (Note 13)
Stockholders' equity:
Common stock, $0.01 par value, 120,000,000 shares authorized; 54,773,061 and 45,194,736 shares issued and 54,769,030 and 45,144,736 shares outstanding at December 31, 2019 and 2018, respectively	548	452
Treasury stock, at cost, 4,031 and 50,000 common shares at December 31, 2019 and 2018, respectively	(53)	(668)
Additional paid-in capital	489,925	300,253
Accumulated other comprehensive income (loss)	20	(127)
Accumulated deficit	(183,143)	(105,873)
Total stockholders' equity	307,297	194,037
Total liabilities and stockholders' equity	372,121	251,313
Series A Convertible Preferred Shares [Member]
Stockholders' equity:
Preferred stock	0	0
Series B Convertible Preferred Shares [Member]
Stockholders' equity:
Preferred stock	$ 0	$ 0

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2019	Dec. 31, 2018
Shareholders' equity:
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	120,000,000	120,000,000
Common stock, shares issued (in shares)	54,773,061	45,194,736
Common stock, shares outstanding (in shares)	54,769,030	45,144,736
Treasury stock, at cost (in shares)	4,031	50,000
Series A Convertible Preferred Shares [Member]
Shareholders' equity:
Preferred stock, shares authorized (in shares)	300,000	300,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Series B Convertible Preferred Shares [Member]
Shareholders' equity:
Preferred stock, shares authorized (in shares)	300,000	300,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Consolidated Statements of Operations [Abstract]
Revenue	$ 0	$ 0
Operating expenses:
Research and development	58,623	53,270
General and administrative	17,528	17,886
Total operating expenses	76,151	71,156
Loss from operations	(76,151)	(71,156)
Research and development incentives	250	186
Interest expense	(5,958)	(6,039)
Interest and other income, net	3,414	1,690
Accretion of discount on investments	1,175	801
Net loss	$ (77,270)	$ (74,518)
Net loss per share attributable to common stockholders - basic and diluted (in dollars per share)	$ (1.58)	$ (1.89)
Weighted-average common shares outstanding - basic and diluted (in shares)	49,010,358	39,377,666

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Consolidated Statements of Comprehensive Loss [Abstract]
Net loss	$ (77,270)	$ (74,518)
Other comprehensive loss
Net unrealized gain (loss) on investments	147	(127)
Total comprehensive loss	$ (77,123)	$ (74,645)

- Definition

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

+ References + Details

Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Preferred Stock [Member] Series A Convertible Preferred Shares [Member]	Preferred Stock [Member] Series B Convertible Preferred Shares [Member]	Common Stock [Member]	Treasury Stock [Member]	Additional Paid in Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Accumulated Deficit [Member]	Total
Beginning Balance at Dec. 31, 2017	$ 16,060	$ 25,406	$ 68	$ 0	$ 5,340	$ 0	$ (31,355)	$ 15,519
Beginning Balance (in shares) at Dec. 31, 2017	128,738	126,909	6,795,627
Conversion of convertible preferred shares into common shares	$ (16,060)	$ (25,406)	$ 194	0	41,272	0	0	0
Conversion of convertible preferred shares into common shares (in shares)	(128,738)	(126,909)	19,475,788
Exchange of common shares in connection with the Reverse Merger	$ 0	$ 0	$ 68	0	85,992	0	0	86,060
Exchange of common shares in connection with the Reverse Merger (in shares)	0	0	6,805,608
Issuance of common stock, net of issuance costs	$ 0	$ 0	$ 115	0	153,907	0	0	154,022
Issuance of common stock, net of issuance costs (in shares)	0	0	11,475,242
Issuance of common stock pursuant to settlement of restricted stock units	$ 0	$ 0	$ 3	0	(3)	0	0	0
Issuance of common stock pursuant to settlement of restricted stock units (in shares)	0	0	271,718
Issuance of common stock pursuant to exercise of stock options	$ 0	$ 0	$ 4	0	144	0	0	148
Issuance of common stock pursuant to exercise of stock options (in shares)	0	0	370,753
Treasury stock purchases	$ 0	$ 0	$ 0	(668)	0	0	0	(668)
Treasury stock purchases (in shares)	0	0	0
Unrealized comprehensive gain (loss) on investments	$ 0	$ 0	$ 0	0	0	(127)	0	(127)
Stock-based compensation	0	0	0	0	13,601	0	0	13,601
Net loss	0	0	0	0	0	0	(74,518)	(74,518)
Ending Balance at Dec. 31, 2018	$ 0	$ 0	$ 452	(668)	300,253	(127)	(105,873)	194,037
Ending Balance (in shares) at Dec. 31, 2018	0	0	45,194,736
Issuance of common stock, net of issuance costs	$ 0	$ 0	$ 96	0	177,664	0	0	177,760
Issuance of common stock, net of issuance costs (in shares)	0	0	9,568,000
Issuance of common stock pursuant to exercise of stock options	$ 0	$ 0	$ 1	0	30	0	0	31
Issuance of common stock pursuant to exercise of stock options (in shares)	0	0	110,325
Treasury stock purchases	$ 0	$ 0	$ 0	(725)	(1)	0	0	(726)
Treasury stock purchases (in shares)	0	0	0
Issuance of treasury stock pursuant to exercise of stock options	$ 0	$ 0	$ 0	(397)	0	0	0	(397)
Issuance of treasury stock pursuant to exercise of stock options (in shares)	0	0	0
Retirement of treasury stock	$ 0	$ 0	$ (1)	1,393	(1,392)	0	0	0
Retirement of treasury stock (in shares)	0	0	(100,000)
Sale of treasury stock	$ 0	$ 0	$ 0	344	0	0	0	344
Sale of treasury stock (in shares)	0	0	0
Unrealized comprehensive gain (loss) on investments	$ 0	$ 0	$ 0	0	0	147	0	147
Stock-based compensation	0	0	0	0	13,371	0	0	13,371
Net loss	0	0	0	0	0	0	(77,270)	(77,270)
Ending Balance at Dec. 31, 2019	$ 0	$ 0	$ 548	$ (53)	$ 489,925	$ 20	$ (183,143)	$ 307,297
Ending Balance (in shares) at Dec. 31, 2019	0	0	54,773,061

Consolidated Statements of Changes in Stockholders' Equity (Parenthetical) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($)
Consolidated Statements of Changes in Stockholders' Equity [Abstract]
Issuance of common shares, issuance costs	$ 9,300

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Operating Activities:
Net loss	$ (77,270)	$ (74,518)
Adjustments to reconcile net loss to net cash used in operating activities:
Accretion of discount on convertible notes	3,602	3,059
Increase in lease liability	0	(161)
Depreciation expense	426	330
Stock-based compensation	13,371	13,601
Loss on disposal of property and equipment	0	317
Accretion of discount on investments	(1,066)	(801)
Changes in operating assets and liabilities:
Prepaid expenses and other assets	(917)	(1,505)
Accounts payable and accrued expenses	(2,722)	5,890
Operating lease liabilities	(87)	0
Net cash used in operating activities	(64,663)	(53,788)
Investing activities:
Cash acquired in connection with the Reverse Merger	0	76,348
Purchases of investments	(184,298)	(141,087)
Proceeds from maturities of investments	168,556	61,276
Proceeds from sale of property and equipment	0	20
Purchases of property and equipment	(23,269)	(1,453)
Payment of security deposit	0	(376)
Net cash used in investing activities	(39,011)	(5,272)
Financing activities:
Proceeds from issuance of common stock, net of issuance costs	177,760	154,022
Issuance of common stock, pursuant to exercise of stock options	31	148
Treasury stock repurchase	0	(668)
Proceeds from sale of treasury stock	344	0
Payment of witholding tax on option exercise	(344)	0
Net cash provided by financing activities	177,791	153,502
Net change in cash, cash equivalents and restricted cash	74,117	94,442
Cash, cash equivalents and restricted cash at beginning of year	112,791	18,349
Cash, cash equivalents and restricted cash at end of year	186,908	112,791
Supplemental disclosure of non-cash financing and investing activities:
Accrued purchases of property and equipment	4,424	0
Accrued purchases of internal use software	226	0
Treasury stock purchases paid in prior year	726	0
Retirement of treasury stock	1,393	0
Witholding tax payable on shares witheld in treasury stock	53	0
Conversion of convertible preferred stock into common stock	0	41,466
Unrealized gain (loss) on investments	147	(127)
Supplemental cash flow information:
Cash paid for interest	2,990	4,485
Cash paid for income taxes	$ 26	$ 2

Nature of Business and Basis of Presentation

12 Months Ended

Dec. 31, 2019

Nature of Business and Basis of Presentation [Abstract]

Nature of Business and Basis of Presentation

1.	Nature of Business and Basis of Presentation

We are a clinical-stage, multi-platform biotechnology company focused on the development of first, only and best-in-class gene therapies, with direct on-target mechanism of action and clear clinical endpoints, for rare and devastating pediatric diseases. We currently have three clinical-stage ex vivo lentiviral vector (“LVV”) programs currently enrolling patients in the US and EU for Fanconi Anemia (“FA”), a genetic defect in the bone marrow that reduces production of blood cells or promotes the production of faulty blood cells, Leukocyte Adhesion Deficiency-I (“LAD-I”), a genetic disorder that causes the immune system to malfunction and Pyruvate Kinase Deficiency (“PKD”), a rare red blood cell autosomal recessive disorder that results in chronic non-spherocytic hemolytic anemia. Of these, both the Phase 2 FA program and the Phase 1/2 LAD-I program are in registration-enabling studies in the US and EU. In addition, in the US we have a clinical stage in vivo adeno-associated virus (“AAV”) program for Danon disease, a multi-organ lysosomal-associated disorder leading to early death due to heart failure. Finally, we have a pre-clinical stage LVV program for Infantile Malignant Osteopetrosis (“IMO”), a genetic disorder characterized by increased bone density and bone mass secondary to impaired bone resorption – this program is anticipated to enter the clinic in 2020. We have global commercialization and development rights to all of these product candidates under royalty-bearing license agreements. Additional work in the discovery stage for an FA CRISPR/CAS9 program as well as a gene therapy program for the less common FA subtypes C and G is ongoing.

Risks and Liquidity

12 Months Ended

Dec. 31, 2019

Risks and Liquidity [Abstract]

Risks and Liquidity

2.	Risks and Liquidity

The Company has not generated any revenue and has incurred losses since inception. Operations of the Company are subject to certain risks and uncertainties, including, among others, uncertainty of drug candidate development, technological uncertainty, uncertainty regarding patents and proprietary rights, having no commercial manufacturing experience, marketing or sales capability or experience, dependency on key personnel, compliance with government regulations and the need to obtain additional financing. Drug candidates currently under development will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval, prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel infrastructure and extensive compliance-reporting capabilities.

The Company’s product candidates are in the development and clinical stage. There can be no assurance that the Company’s research and development will be successfully completed, that adequate protection for the Company’s intellectual property will be obtained, that any products developed will obtain necessary government approval or that any approved products will be commercially viable. Even if the Company’s product development efforts are successful, it is uncertain when, if ever, the Company will generate significant revenue from product sales. The Company operates in an environment of rapid change in technology and substantial competition from pharmaceutical and biotechnology companies.

The Company’s consolidated financial statements have been prepared on the basis of continuity of operations, realization of assets and the satisfaction of liabilities in the ordinary course of business. The Company has experienced negative cash flows from operations and had an accumulated deficit of $183.1 million as of December 31, 2019. As of December 31, 2019, the Company has $304.1 million of cash, cash equivalents and investments. During the year ended December 31, 2019, the Company received net proceeds of $177.8 million from the completion on April 18, 2019, and December 10, 2019 of public offerings of 5,175,000 and 4,393,000 shares of common stock, respectively. Rocket expects such resources will be sufficient to fund its operating expenses and capital expenditure requirements into 2022.

In the longer term, the future viability of the Company is dependent on its ability to generate cash from operating activities or to raise additional capital to finance its operations. The Company’s failure to raise capital as and when needed could have a negative impact on its financial condition and ability to pursue its business strategies.

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2019

Summary of Significant Accounting Policies [Abstract]

Summary of Significant Accounting Policies

3.	Summary of Significant Accounting Policies

Principles of Consolidation

The consolidated financial statements represent the consolidation of the accounts of the Company and its subsidiaries in conformity with accounting principles generally accepted in the United States (“US GAAP”). All intercompany accounts have been eliminated in consolidation.

Use of Estimates

The preparation of the consolidated financial statements in conformity with US GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Significant estimates and assumptions reflected in these consolidated financial statements include but are not limited to fair value under acquisition accounting, goodwill impairment, the accrual of research and development expenses, the valuation of equity transactions, lease liabilities and stock-based awards. Changes in estimates and assumptions are reflected in reported results in the period in which they become known. Actual results could differ from those estimates.

Cash, Cash Equivalents and Restricted Cash

Cash, cash equivalents and restricted cash consists of bank deposits, certificates of deposit and money market accounts with financial institutions. Cash equivalents are carried at cost which approximates fair value due to their short-term nature and which the Company believes do not have a material exposure to credit risk. The Company considers all highly liquid investments with maturities of three months or less from the date of purchase to be cash equivalents. The Company’s cash and cash equivalent accounts, at times, may exceed federally insured limits. The Company has not experienced any losses in such accounts.

Restricted cash consists of deposits collateralizing letters of credit issued by a bank in connection with the Company’s operating leases (see Note 13 “Commitments and Contingencies” for additional disclosures) and a deposit collateralizing a letter of credit issued by a bank supporting the Company’s Corporate Credit Card. Cash, cash equivalents and restricted cash consist of the following:

	December 31, 2019		December 31, 2018

Cash and cash equivalents	$	185,383	$	111,355
Restricted cash		1,525		1,436
	$	186,908	$	112,791

Government Grants

Research and development expense is presented net of reimbursements from the California Institute for Regenerative Medicine (“CIRM”), which are recognized over the period necessary to match the reimbursement with the related costs when it is probable that the Company has complied with the CIRM conditions and will receive the reimbursement. During the year ended December 31, 2019, we offset $1.2 million of grant funds against research and development (“R&D”) expenses (See Note 16 “CIRM Grant” for additional disclosure).

Concentrations of credit risk and off-balance sheet risk

Financial instruments that subject the Company to credit risk primarily consist of cash and cash equivalents and available-for-sale securities. The Company maintains its cash and cash equivalent balances with high-quality financial institutions and, consequently, the Company believes that such funds are subject to minimal credit risk. The Company’s marketable securities consist of U.S. Treasury securities, and Corporate, Government and Municipal Bonds. The Company has adopted an investment policy that limits the amounts the Company may invest in any one type of investment and requires all investments held by the Company to be at least AA+/Aa1 rated, thereby reducing credit risk exposure.

Investments

Investments consist of investments in United States Treasury securities and Corporate, Government and Municipal Bonds. Management determines the appropriate classification of these securities at the time they are acquired and evaluates the appropriateness of such classifications at each balance sheet date. The Company classifies its investments as available-for-sale pursuant to Financial Accounting Standards Board (“FASB”) Accounting Standard Codification (“ASC”) 320, Investments—Debt and Equity Securities. Investments are recorded at fair value, with unrealized gains and losses included as a component of accumulated other comprehensive loss in stockholders’ equity and a component of total comprehensive loss in the consolidated statements of comprehensive loss, until realized. Realized gains and losses are included in investment income on a specific-identification basis. There were no realized gains or losses on investments for the years ended December 31, 2019 and 2018. There was $0.1 million of net unrealized gain and $0.1 million of net unrealized losses on investments for the years ended December 31, 2019 and 2018, respectively.

Goodwill

Business combinations are accounted for under the acquisition method. The total cost of an acquisition is allocated to the underlying identifiable net assets, based on their respective estimated fair values as of the acquisition date. Determining the fair value of assets acquired and liabilities assumed requires management’s judgment and often involves the use of significant estimates and assumptions, including assumptions with respect to future cash inflows and outflows, discount rates, asset lives and market multiples, among other items. Assets acquired and liabilities assumed are recorded at their estimated fair values. The excess of the purchase price over the estimated fair values of the net assets acquired is recorded as goodwill.

Goodwill is tested for impairment annually as of December 31, or more frequently when events or changes in circumstances indicate that the asset might be impaired. Examples of such events or circumstances include, but are not limited to, a significant adverse change in legal or business climate, an adverse regulatory action or unanticipated competition. The Company has one segment and one reporting unit and as such reviews goodwill for impairment at the consolidated level.

When testing goodwill, the Company has the option to first assess qualitative factors for reporting units that carry goodwill. The qualitative assessment includes assessing the totality of relevant events and circumstances that affect the fair value or carrying value of the reporting unit. These events and circumstances include macroeconomic conditions, industry and competitive environment conditions, overall financial performance, reporting unit specific events and market considerations. The Company also considers recent valuations of the reporting unit, including the magnitude of the difference between the most recent fair value estimate and the carrying value, as well as both positive and adverse events and circumstances, and the extent to which each of the events and circumstances identified may affect the comparison of a reporting unit’s fair value with its carrying value. If the qualitative assessment results in a conclusion that it is more likely than not that the fair value of a reporting unit exceeds the carrying value, then no further testing is performed for that reporting unit.

In January 2017, the FASB issued ASU No. 2017-04, “Intangibles- Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment”, an amendment to simplify the subsequent quantitative measurement of goodwill by eliminating step two from the goodwill impairment test. We early adopted this guidance as of January 1, 2018. An entity will recognize an impairment charge for the amount by which the carrying amount of a reporting unit exceeds its fair value, not to exceed the total amount of goodwill allocated to the reporting unit. An entity still has the option to perform the qualitative test for a reporting unit to determine if the quantitative impairment test is necessary. The Company performed the qualitative assessment of its goodwill and determined that it is more likely than not that the fair value of a reporting unit exceeds the carrying value of the reporting unit. As a result, the Company has determined there was no goodwill impairment for the years ended December 31, 2019, and 2018.

Property and Equipment

Property and equipment are stated at cost less accumulated depreciation. Depreciation expense is recognized using the straight-line method over the useful life of the asset. The estimated useful lives are three to fifteen years. The Company capitalizes purchases of laboratory equipment and construction costs in relation to the facility at Cranbury, New Jersey, since it has been determined these assets have alternative future uses to the Company. Expenditures for repairs and maintenance of assets are charged to expense as incurred. Upon retirement or sale, the cost and related accumulated depreciation of assets disposed of are removed from the accounts and any resulting gain or loss is included in loss from operations.

Internal Use Software

The Company capitalizes certain external costs incurred to acquire and develop internal use software, principally related to our enterprise resource planning (“ERP”) systems. As of December 31, 2019, the ERP system has not been activated.

Impairment of Long-Lived Assets

The Company reviews long-lived assets for impairment whenever events or changes in circumstances indicate that the asset’s carrying amount may not be recoverable. The Company conducted our long-lived asset impairment analyses in accordance with ASC 360-10-15, Impairment or Disposal of Long-Lived Assets.”ASC 360-10-15 requires us to group assets and liabilities at the lowest level for which identifiable cash flows are largely independent of the cash flows of other assets and liabilities and evaluate the asset group against the sum of the undiscounted future cash flows. If the undiscounted cash flows do not indicate the carrying amount of the asset is recoverable, an impairment charge is measured as the amount by which the carrying amount of the asset group exceeds its fair value based on discounted cash flow analysis or appraisals. Following this review, there is no impairment of long-lived assets for the years ended December 31, 2019 and 2018.

Fair Value Measurements

The Company is required to disclose information on all assets and liabilities reported at fair value that enables an assessment of the inputs used in determining the reported fair values. FASB ASC 820, Fair Value Measurements and Disclosures (“ASC 820”), establishes a hierarchy of inputs used when available. Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the inputs that market participants would use in pricing the asset or liability and are developed based on the best information available in the circumstances. The fair value hierarchy applies only to the valuation inputs used in determining the reported fair value of the investments and is not a measure of the investment credit quality. The three levels of the fair value hierarchy are described below:

Level 1—Valuations based on unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date.

Level 2—Valuations based on quoted prices for similar assets or liabilities in markets that are not active or for which all significant inputs are observable, either directly or indirectly.

Level 3—Valuations that require inputs that reflect the Company’s own assumptions that are both significant to the fair value measurement and unobservable.

To the extent that valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. The fair value of the Company’s financial instruments, including cash and cash equivalents, restricted cash, deposits, accounts payable and accrued expenses approximate their respective carrying values due to the short-term nature of these instruments. The fair value of the 2021 Convertible Notes as of December 31, 2019 was approximately $54.5 million. The Company’s assets and liabilities measured at fair value on a recurring basis include its short and long term investments.

Research and Development

R&D costs, which include salaries and staff costs, license costs, regulatory and scientific consulting fees, as well as contract research, and stock-based compensation expense, are accounted for in accordance with ASC Topic 730, Research and Development (“ASC 730”).

The Company does not currently have any commercial biopharmaceutical products, and does not expect to have any for several years, if at all. Accordingly, R&D costs are expensed as incurred. While certain of the Company’s R&D costs may have future benefits, the policy of expensing all R&D expenditures is predicated on the fact that the Company has no history of successful commercialization of product candidates to base any estimate of the number of future periods that would be benefited.

Foreign Currency Transactions

Certain transactions during the years ended December 31, 2019 and 2018 are denominated in Euros. Gains and losses on foreign currency transactions were not significant for the years ended December 31, 2019 and 2018.

Treasury Stock

The Company records treasury stock at cost.

Stock-Based Compensation

The Company measures the compensation expense of employee and nonemployee services received in exchange for an award of equity instruments based on the fair value of the award on the grant date. That cost is recognized on a straight-line basis over the period during which the employee and nonemployee is required to provide service in exchange for the award. The fair value of options on the date of grant is calculated using the Black-Scholes option pricing model based on key assumptions such as stock price, expected volatility and expected term. The Company’s estimates of these assumptions are primarily based on the trading price of the Company’s stock, historical data, peer company data and judgment regarding future trends and factors.

The Company classifies stock-based compensation expense in its statement of operations in the same manner in which the award recipient’s payroll costs and services are classified or in which the award recipient’s service payments are classified.

The Company recognizes compensation expense for at least the portion of awards that are vested. Forfeitures are accounted for as they occur.

Effective July 1, 2018, the Company adopted ASU No. 2018-07, Compensation—Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting (“ASU 2018-07”), which expands the scope of Topic 718 to include stock-based payment awards to nonemployees. As a result, stock-based awards granted to consultants and non-employees are accounted for in the same manner as awards granted to employees and directors as described above. Prior to the adoption of ASU 2018-07, for stock-based awards granted to consultants and non-employees, the Company recognized compensation expense over the period during which services are rendered by such consultants and non-employees until completed. At the end of each financial reporting period prior to completion of the service, the estimated fair value of these awards was re-measured using the then-current fair value of our common stock and updated assumption inputs in the Black-Scholes option-pricing model.

NYC Biotechnology Tax Credit Program

New York City allows investors and owners of emerging technology companies focused on biotechnology to claim a tax credit against the General Corporation Tax and Unincorporated Business Tax for amounts paid or incurred for certain facilities, operations, and employee training in New York City. The credit is recognized as research and development incentives when approved by New York City of the eligibility for the credit and the credit amount. During the years ended December 31, 2019 and 2018, the Company recorded research and development incentive income of $0.3 million and $0.2 million, respectively.

Income Taxes

The Company accounts for income taxes under the asset and liability method. The Company recognizes deferred tax assets and liabilities for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases, as well as for operating loss and tax credit carry-forwards. The Company measures deferred tax assets and liabilities using enacted tax rates expected to apply to taxable income in the years in which the Company expects to recover or settle those temporary differences. The Company recognizes the effect of a change in tax rates on deferred tax assets and liabilities in the results of operations in the period that includes the enactment date. The Company reduces the measurement of a deferred tax asset, if necessary, by a valuation allowance if it is more likely than not that the Company will not realize some or all of the deferred tax asset.

The Company’s deferred tax assets relate primarily to its net operating loss carryforwards and other balance sheet differences. In accordance with ASC 740 “Income Taxes”, the Company recorded a full valuation allowance to fully offset the net deferred tax asset because it is not more likely than not that the Company will realize future benefits associated with these deferred tax assets at December 31, 2019 and 2018.

The Company accounts for uncertainty in income taxes recognized in the financial statements by applying a two-step process to determine the amount of tax benefit to be recognized. First, the tax position must be evaluated to determine the likelihood that it will be sustained upon external examination by the taxing authorities. If the tax position is deemed more-likely-than-not to be sustained, the tax position is then assessed to determine the amount of benefit to recognize in the financial statements. The amount of the benefit that may be recognized is the largest amount that has a greater than 50% likelihood of being realized upon ultimate settlement. The provision for income taxes includes the effects of any resulting tax reserves, or unrecognized tax benefits, that are considered appropriate as well as the related net interest and penalties.

Net Loss Per Share

The Company calculates net loss per share in accordance with FASB ASC 260, Earnings per Share. Basic net loss per share attributable to common shareholders is computed by dividing the net loss attributable to common shareholders by the weighted average number of common shares outstanding for the period. Diluted net loss attributable to common shareholders is computed by adjusting net loss attributable to common shareholders to reallocate undistributed earnings based on the potential impact of dilutive securities. Diluted net loss per share attributable to common shareholders is computed by dividing the diluted net loss attributable to common shareholders by the weighted average number of common shares outstanding for the period, including potential dilutive common shares. For purposes of this calculation, outstanding options are considered potential dilutive common shares.

Segment Reporting

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 segment.

Comprehensive Loss

Comprehensive loss is defined as the change in equity of a business enterprise during a period from transactions, and other events and circumstances from non-owner sources, and consists of net loss and changes in unrealized gains and losses on investments.

Recent Accounting Pronouncements

Other than the adoption of ASU 2016-02 (see Note 13), there were no other recent accounting standards that impacted the Company for the year ended December 31, 2019.

2018 Reverse-Merger Acquisition Accounting

12 Months Ended

Dec. 31, 2019

2018 Reverse-Merger Acquisition Accounting [Abstract]

2018 Reverse-Merger Acquisition Accounting

4.	2018 Reverse-Merger Acquisition Accounting

On January 4, 2018, Rome Merger Sub (“Merger Sub”), a wholly owned subsidiary of Inotek Pharmaceuticals Corporation (“Inotek”), completed its merger with and into Rocket Pharmaceuticals, Ltd. (“Rocket Ltd”), with Rocket Ltd surviving as a wholly owned subsidiary of Inotek. This transaction is referred to as the “Reverse Merger.” The Reverse Merger was effected pursuant to an Agreement and Plan of Merger and Reorganization (the “Merger Agreement”), dated as of September 12, 2017, by and among Inotek, Rocket Ltd and Rome Merger Sub.

The Reverse Merger has been accounted for as a reverse acquisition under the acquisition method of accounting where Rocket Ltd is considered the accounting acquirer and Inotek is the acquired company for financial reporting purposes. Rocket Ltd was determined to be the accounting acquirer based on the terms of the Merger Agreement and other factors, such as relative voting rights and the composition of the combined company’s board of directors and senior management. The pre-acquisition financial statements of Rocket Ltd became the historical financial statements of Rocket following completion of the Reverse Merger. The historical financial statements, outstanding shares and all other historical share information have been adjusted by multiplying the respective share amount by the Exchange Ratio as if the Exchange Ratio had been in effect for all periods presented.

The identifiable assets and liabilities of Inotek are allocated in the Company’s consolidated financial statements at their fair values at the acquisition date, January 4, 2018. Goodwill is calculated as the excess value of consideration paid over the fair value of assets acquired and liabilities assumed.

The acquisition-date fair value of the consideration transferred is as follows:

Number of shares of the combined company owned by Inotek shareholders		6,805,608
Number of shares issuable in connection with fully vested RSUs of Inotek immediately prior to the Reverse Merger		271,718
Inotek common stock on the acquisition date		7,077,326
Price per share of Inotek common stock on acquisition date	$	12.16
Total purchase price	$	86,060

The following table summarizes the fair value purchase price allocation of the assets acquired and liabilities assumed at the date of acquisition which is subject to adjustment as the Company finalizes it valuation:

Cash and cash equivalents	$	76,348
Short term investments		21,292
Prepaid expense and other assets		1,041
Property and equipment		256
Deposits		168
Goodwill		30,815
Accounts payable and accrued expenses		(4,961	)
Convertible notes		(38,388	)
Unfavorable lease liability		(511	)
Net assets acquired	$	86,060

The goodwill of $30.8 million represents the premium over the purchase price. Goodwill is mainly attributable to the value of cash and cash equivalents and short term investments acquired as of the acquisition date and access to capital markets. The allocation of the purchase price with the assistance of a third party valuation, is based on certain management assumptions (Level 3 inputs).

Fair Value of Financial Instruments

12 Months Ended

Dec. 31, 2019

Fair Value of Financial Instruments [Abstract]

Fair Value of Financial Instruments

5.	Fair Value of Financial Instruments

Items measured at fair value on a recurring basis are the Company’s investments. The following table sets forth the Company’s financial instruments that were measured at fair value on a recurring basis by level within the fair value hierarchy:

	Fair Value Measurements as of December 31, 2019 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Money market mutual funds (included in cash and cash equivalents)	$	72,114	$	-	$	-	$	72,114
Cash		7,542		-		-		7,542
		79,656		-		-		79,656

United States Treasury securities		75,464		-		-		75,464
Government Bonds		-		8,000		-		8,000
Corporate Bonds		-		29,268		-		29,268
Municipal Bonds		-		6,000		-		6,000
Investments		75,464		43,268		-		118,732

	$	155,120	$	43,268	$	-	$	198,388

	Fair Value Measurements as of
	December 31, 2018 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Money market mutual funds (included in cash and cash equivalents)	$	30,552	$	-	$	-	$	30,552

United States Treasury securities		101,777		-		-		101,777
Investments		101,777		-		-		101,777

	$	132,329	$	-	$	-	$	132,329

The Company classifies its money market mutual funds and U.S. Treasury securities as Level 1 assets under the fair value hierarchy, as these assets have been valued using quoted market prices in active markets without any valuation adjustment. The company classifies its Government, Corporate and Municipal Bonds as Level 2 assets as these assets are not traded in an active market and have been valued through a third-party pricing service based on quoted prices for similar assets.

The fair value of the 2021 Convertible Notes as of December 31, 2019 was approximately $54.5 million.

Property and Equipment

12 Months Ended

Dec. 31, 2019

Property and Equipment [Abstract]

Property and Equipment

6.	Property and Equipment

The Company’s property and equipment consisted of the following:

	December 31, 2019			December 31, 2018
Laboratory equipment	$	1,910		$	1,556
Computer equipment		179			179
Furniture and fixtures		273			273
Leasehold improvements		29			29
Construction costs in progress		27,809			469
		30,200			2,506
Less: accumulated depreciation		(905	)		(479	)
	$	29,295		$	2,027

Construction costs in progress comprise costs associated with the build out of the Company’s research, manufacturing and office facilities under an operating lease in Cranbury, NJ. The costs are deemed to be landlord improvement costs. See Note 13 “Commitments and Contingencies” for additional disclosures. During the years ended December 31, 2019 and 2018, the Company capitalized interest in relation to the construction costs of $0.7 million and $0, and recognized $0.4 million and $0.3 million of depreciation expense, respectively.

Accounts Payable and Accrued Expenses

12 Months Ended

Dec. 31, 2019

Accounts Payable and Accrued Expenses [Abstract]

Accounts Payable and Accrued Expenses

7.	Accounts Payable and Accrued Expenses

At December 31, 2019 and 2018, the Company’s accounts payable and accrued expenses consisted of the following:

	December 31, 2019		December 31, 2018
Research and development	$	7,418	$	10,414
Construction costs in progress		4,424		-
Bonus		2,459		1,774
Accrued interest		1,241		1,241
Government grant payable		562		534
Professional fees		553		690
Accrued vacation		129		123
Severance and benefits		-		7
Internal use software		226		-
Other		340		589
	$	17,352	$	15,372

2021 Convertible Notes Payable

12 Months Ended

Dec. 31, 2019

2021 Convertible Notes Payable [Abstract]

2021 Convertible Notes Payable

8.	2021 Convertible Notes Payable

On January 4, 2018, in connection with the Reverse Merger, Inotek’s obligations under its outstanding convertible notes, with an aggregate principal value of $52.0 million, were assumed by the Company (the “2021 Convertible Notes”). The 2021 Convertible Notes were issued in 2016 and mature on August 1, 2021 (“Maturity Date”). The 2021 Convertible Notes are unsecured, accrue interest at a rate of 5.75% per annum and interest is payable semi-annually on February 1 and August 1 of each year. Each holder of a 2021 Convertible Notes (the “Holder”) has the option until the close of business on the second business day immediately preceding the Maturity Date to convert all, or any portion, of the 2021 Convertible Notes held by it at a conversion rate of 31.1876 shares of the Company’s common stock per $1 principal amount of 2021 Convertible Notes (the “Conversion Rate”) which is $32.08 per share. The Conversion Rate is subject to adjustment from time to time upon the occurrence of certain events, including the issuance of stock dividends and payment of cash dividends.

In addition, in certain circumstances, the Conversion Rate will be increased in respect of a Holder’s conversion of 2021 Convertible Notes in connection with the occurrence of one or more corporate events specified in the indenture (as supplemented, the “Indenture”) governing the 2021 Convertible Notes (each such specified corporate event, a “Make-Whole Fundamental Change”) that occurs prior to the Maturity Date (a “Make-Whole Fundamental Change Conversion”) or in respect of a Holder’s voluntary conversion of 2021 Convertible Notes other than in connection with a Make-Whole Fundamental Change (a “Voluntary Conversion”). In connection with a Make-Whole Fundamental Change Conversion or a Voluntary Conversion, the Company will increase the Conversion Rate for the 2021 Convertible Notes surrendered for conversion by a number of additional shares of the Company’s common stock set forth in the Additional Shares Make-Whole Table in the Indenture, based on the applicable Stock Price (as defined in the Indenture) and Effective Date (as defined in the Indenture) for such conversion. The additional shares potentially issuable in connection with a Make-Whole Fundamental Change Conversion or a Voluntary Conversion range from 0 to 6.2375 per $1 principal amount of 2021 Convertible Notes, subject to adjustment. If the Stock Price applicable to any conversion is greater than $160.00 per share, the Conversion Rate will not be increased. If the Stock Price applicable to any conversion is less than $26.72 per share, the Conversion Rate in connection with a Make-Whole Fundamental Change Conversion will not be increased but it will be increased by 6.2375 shares in connection with a Voluntary Conversion. Upon conversion, Holders of the 2021 Convertible Notes will receive shares of the Company’s common stock and cash in lieu of fractional shares.

Upon the occurrence of a Fundamental Change, the occurrence of certain change of control transactions or delisting events (as defined in the Indenture), each Holder may require the Company to repurchase for cash all or any portion of the 2021 Convertible Notes held by such Holder at a repurchase price equal to 100% of the principal amount thereof, plus accrued and unpaid interest thereon.

The Company, at its option, may redeem for cash all or any portion of the 2021 Convertible Notes if the last reported sale price of a share of the Company’s common stock is equal to or greater than 200% of the conversion price for the 2021 Convertible Notes then in effect for at least 20 trading days (whether or not consecutive) during any 30 consecutive trading day period (including the last trading day of such period) ending within the five trading days immediately preceding the date on which the Company provides notice of redemption, at a redemption price equal to 100% of the principal amount of the 2021 Convertible Notes to be redeemed, plus accrued and unpaid interest to, but excluding, the redemption date.

If an Event of Default (as defined in the Indenture), other than certain events of bankruptcy, insolvency or reorganization involving the Company, occurs and is continuing, the trustee under the Indenture or the Holders of at least 25% in principal amount of the outstanding 2021 Convertible Notes may declare 100% of the principal of and accrued and unpaid interest, if any, on all of the 2021 Convertible Notes to be due and payable immediately. Upon the occurrence of an Event of Default relating to bankruptcy, insolvency or reorganization involving the Company, 100% of the principal of and accrued and unpaid interest, if any, on all of the 2021 Convertible Notes would become due and payable automatically.

Notwithstanding the foregoing, the Indenture provides that, to the extent the Company elects, the sole remedy for an Event of Default relating to certain failures by the Company to comply with certain reporting covenants in the Indenture, will (i) for the first 90 days after the occurrence of such an Event of Default, consist exclusively of the right to receive additional interest on the 2021 Convertible Notes at a rate equal to 0.25% per annum of the principal amount of the 2021 Convertible Notes outstanding for each day during such 90-day period on which such an Event of Default is continuing and (ii) for the period from, and including, the 91st day after the occurrence of such an Event of Default to, and including, the 180th day after the occurrence of such an Event of Default, consist exclusively of the right to receive additional interest on the 2021 Convertible Notes at a rate equal to 0.50% per annum of the principal amount of the 2021 Convertible Notes outstanding for each day during such additional 90-day period on which such an Event of Default is continuing (such additional interest, “Additional Interest”). After 180 days, if such Event of Default is not cured or waived, the 2021 Convertible Notes would be subject to acceleration in accordance with the Indenture.

The 2021 Convertible Notes are considered a hybrid financial instrument consisting of a fixed interest rate “host” and various embedded features that required evaluation as potential embedded derivatives under FASB ASC 815, Derivatives and Hedging (“ASC 815”). Based on the nature of the host instrument and the embedded features, management concluded that none of the conversion, put and redemption features required bifurcation and separate accounting from the host instrument. The Company determined that the Additional Interest was an embedded derivative that contains non-credit related events of default. As a result, the Additional Interest feature required bifurcation and separate accounting under ASC 815. Based on the amount of Additional Interest that would be owed and the likelihood of occurrence, Rocket estimated that the fair value of the Additional Interest feature to be immaterial as of December 31, 2019 and 2018.

As of December 31, 2019, the stated interest rate was 5.75%, and the effective interest rate was 15.3%.

The table below summarizes the carrying value of the 2021 Convertible Notes:

	December 31, 2019			December 31, 2018

Principal amount	$	52,000		$	52,000
Discount		(6,951	)		(10,553	)
Carrying value	$	45,049		$	41,447

Accretion of the 2021 Convertible Notes discount was $3.6 million and $3.1 million for the years ended December 31, 2019 and 2018, respectively.

On February 10, 2020, the Company entered into separate, privately negotiated exchange agreements (the “Exchange Agreements”) with certain holders of the 2021 Convertible Notes (see Note 19).

Shareholders' Equity

12 Months Ended

Dec. 31, 2019

Stockholders' Equity [Abstract]

Shareholders' Equity

9.	Stockholders’ Equity

Treasury Stock

On December 27 and 28, 2018, the Company repurchased 100,000 shares of its common stock for aggregate consideration of approximately $1.4 million. The repurchases were made on the Nasdaq Stock Market at prevailing market prices in accordance with SEC Rule 10b-18. 50,000 of the shares repurchased at an average price of $13.36 by the Company settled on December 31, 2018 and was recorded as treasury stock. The remaining 50,000 shares repurchased at an average price of $14.50 resulting in $0.7 million, was recorded as a prepaid expense as of December 31, 2018. On January 2, 2019, these shares were settled and the $0.7 million was recorded as treasury stock. In January 2019, the total of 100,000 of treasury stock shares were retired and the total of $1.3 million was reclassified to additional paid in capital.

The Company sold 100,000 shares of common stock (the “Shares”) for $1.4 million to RTW Innovation Master Fund, Ltd. (“RTW Innovation”), which is an affiliate of the Company and is managed by RTW. RTW Innovation purchased the shares for a per-Share price of $13.93, plus an amount equal to the Company’s expenses incurred in connection with the Repurchases (including broker’s commissions) and the issuance of the Shares. The offering and sale of the Shares was completed as a private placement under Section 4(a) (2) of the Securities Act of 1933, as amended and included in the common shares outstanding as of December 31, 2018.

On June 25, 2019, the Company recorded treasury stock of $0.3 million for shares withheld to pay the payroll tax liability of an option exercise. These shares were sold in November 2019 for $0.3 million.

As of December 31, 2019, the Company recorded treasury stock of $0.1 million for the shares withheld to pay the payroll tax liability of an option exercise. The related payroll tax liability is included in the consolidated balance sheets as of December 31, 2019 within accounts payable and accrued expenses.

Public Offerings

On January 26, 2018, the Company completed a public offering of 6,325,000 shares of common stock, which included the full exercise of the underwriters’ options to purchase 825,000 additional shares of its common stock at a public offering price of $13.25 per share. The gross proceeds to Rocket from the January 2018 public offering were approximately $83.8 million, net of $5.3 million of offering costs, commission and legal and other expenses for net proceeds from the offering of $78.5 million.

On November 30, 2018, the Company completed a public offering of 4,082,500 shares of its common stock, which includes the full exercise of the underwriters’ option to purchase 532,500 additional shares of its common stock, at a public offering price of $15.50 per share. The gross proceeds to Rocket from the November 2018 public offering were approximately $63.3 million, net of $4.0 million of offering costs, commissions, legal and other expenses for a net proceeds from the offering of $59.3 million.

In addition to the shares sold in the November 2018 public offering, on November 30, 2018 Rocket completed a concurrent sale of 967,742 shares of common stock at a price of $15.50 per share, for gross proceeds of $15.0 million, net of offering costs of $0.2 million for net proceeds of $14.8 million, in a private placement to RTW Investments, LP, (“RTW”) an existing stockholder of the Company and an affiliate of Roderick Wong, the chairman of Rocket’s board of directors. The sale of these shares was not registered under the Securities Act of 1933, as amended, and such shares are subject to customary resale restrictions. Additionally, RTW signed a 90-day lock-up with respect to all shares of Rocket beneficially held by RTW.

On April 18, 2019, the Company completed a public offering of 5,175,000 shares of common stock, which includes the full exercise of the underwriters’ option to purchase an additional 675,000 shares of our common stock, at a public offering price of $17.50 per share. The gross proceeds to Rocket from the April 2019 public offering were approximately $90.6 million, after deducting $4.5 million of offering costs, commissions, legal and other expenses for a net proceeds from the offering of $86.1 million.

On December 10, 2019, the Company completed a public offering of 4,393,000 shares of common stock, which includes the full exercise of the underwriters’ option to purchase an additional 573,000 shares of our common stock, at a public offering price of $22.25 per share. The gross proceeds to Rocket from the December 2019 public offering were approximately $99.7 million, net of $6.1 million of offering costs, commissions, legal and other expenses for a net proceeds from the offering of $91.7 million.

Stock-Based Awards

12 Months Ended

Dec. 31, 2019

Stock-Based Awards [Abstract]

Stock-Based Awards

10.	Stock-Based Awards

Stock Option Valuation

Effective July 1, 2018, the Company adopted ASU No. 2018-07, Compensation—Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting (“ASU 2018-07”).

The table below for the years ended December 31, 2019 and 2018 is post adoption of ASU 2018-07. The weighted average assumptions that the Company used in the Black-Scholes pricing model to determine the fair value of the stock options granted to employees, non-employees and directors were as follows:

	Years Ended December 31,
	2019			2018

Risk-free interest rate		2.26	%		2.64	%
Expected term (in years)		5.81			5.85
Expected volatility		75.71	%		87.70	%
Expected dividend yield		0.00	%		0.00	%
Exercise price	$	14.47		$	17.82
Fair value of common stock	$	14.47		$	17.98

The following table summarizes stock option activity for the years ended December 31, 2019 and 2018, under the Revised 2014 Plan:

	Number of Shares			Weighted Average Exercise Price		Weighted Average Contractual Term (Years)		Aggregate Intrinsic Value

Outstanding as of December 31, 2017		6,959,347		$	1.06		8.17	$	27,175
Assumed as part of merger with Inotek		523,456			2.01		6.78
Granted		1,650,878			17.82		9.26
Exercised		(370,753	)		1.27		-
Forfeited		(146,931	)		3.02
Outstanding as of December 31, 2018		8,615,997		$	4.48		7.51	$	94,474
Granted		1,706,116			14.47		9.29
Exercised		(110,325	)		2.31				1,429
Cancelled		(448,247	)		10.83
Outstanding as of December 31, 2019		9,763,541		$	5.96		6.96		164,021


Options vested and exercisable as of December 31, 2019		7,307,751		$	3.06		6.30	$	143,996
Options unvested as of December 31, 2019		2,455,790		$	14.61		8.91

The weighted average grant-date fair value per share of stock options granted during the years ended December 31, 2019 and 2018 was $9.58 and $13.21, respectively.

The total fair value of options vested during the years ended December 31, 2019 and 2018 was $63.1 million and $91.3 million, respectively.

Stock-Based Compensation

	Year Ended December 31,
	2019		2018

Research and development	$	6,153	$	7,375
General and administrative		7,218		6,226
Total	$	13,371	$	13,601

As of December 31, 2019, the Company had an aggregate of $19.3 million of unrecognized stock-based compensation expense, which is expected to be recognized over the weighted average period of 1.74 years.

Net Loss Per Share

12 Months Ended

Dec. 31, 2019

Net Loss Per Share [Abstract]

Net Loss Per Share

11.	Net Loss Per Share

Basic and diluted net loss per share attributable to common stockholders was calculated as follows:

	For the Years Ended December 31,
	2019			2018

Numerator:
Net loss attributable to common stockholders	$	(77,270	)	$	(74,518	)
Denominator:
Weighted-average common shares outstanding - basic and diluted		49,010,358			39,377,666
Net loss per share attributable to common stockholders - basic and diluted	$	(1.58	)	$	(1.89	)

The Company excluded the following potential shares of common stock, presented based on amounts outstanding at each period end, from the computation of diluted net loss per share attributable to common stockholders for the periods indicated because including them would have had an anti-dilutive effect:

	For the Years Ended December 31,
	2019		2018
Shares issuable upon conversion of the 2021 Convertible Notes		1,620,948		1,620,948
Warrants exercisable for common shares		14,102		14,102
Options to purchase common shares		9,763,541		8,615,997
		11,398,591		10,251,047

The Company has warrants outstanding as of December 31, 2019 and 2018, convertible into 14,102 of common shares at an exercise price of $24.82 per share which expire on June 28, 2023.

Income Taxes

12 Months Ended

Dec. 31, 2019

Income Taxes [Abstract]

Income Taxes

12.	Income Taxes

No provision for federal or state income taxes was recorded during the years ended December 31, 2019 and 2018, as the Company incurred operating losses and maintains a full valuation allowance against its net deferred tax assets.

A reconciliation of income tax benefit computed at the statutory federal income tax rate to income taxes as reflected in the financial statements is as follows:

	For the years ended December 31,
	2019			2018
U.S. federal tax at statutory rate		21.0%			21.0%
Change in state tax apportionment		(17.4%	)		15.8%
Stock compensation		(0.7%	)		0.0%
Section 382 limitation		0.0%			(38.7%	)
Valuation allowance		(5.1%	)		3.5%
Other		2.1%			(1.6%	)
Effective tax rate		0%			0%

The significant components of the Company’s deferred income tax assets and liabilities after applying the enacted corporate tax rates are as follows:

	For the years ended December 31,
	2019			2018
Deferred income tax assets (liabilities)
Net operating losses (“NOL”) and credit carryforwards	$	20,988		$	28,400
Capitalized research and development costs		27,652			17,098
Other		643			1,385
Stock-based compensation		3,896			4,563
Debt discount		(1,460	)		(3,652	)
Valuation allowance		(51,719	)		(47,794	)
Net deferred income tax asset	$	-		$	-

As of December 31, 2019, the Company had federal and state net operating loss carryforwards of approximately $62.4 million and $2.2 million, respectively, which begin to expire in 2025. Additionally, $28.3 million of the Federal NOLs can be carried forward indefinitely.

As required by ASC 740, Income Taxes, management of Rocket has evaluated the positive and negative evidence bearing upon the realizability of its deferred tax assets, which are comprised principally of NOL carryforwards and capitalized research and development costs. As a result of the fact that Rocket has incurred tax losses from inception, management has determined that it is more likely than not that Rocket will not recognize the benefits of federal and state net deferred tax assets and, as a result, a full valuation allowance has been established against its net deferred tax assets as of December 31, 2019 and 2018. Rocket has offset certain deferred tax liabilities with deferred tax assets that are expected to generate offsetting deductions within the same period. During the years ended December 31, 2019 and 2018, the valuation allowance increased by $3.9 million and $46.6 million, respectively. Realization of deferred tax assets is dependent upon the generation of future taxable income.

Under Internal Revenue Code Section 382, if a corporation undergoes an “ownership change,” the corporation’s ability to use its pre-change NOL carryforwards and other pre-change tax attributes to offset its post-change income may be limited. The Company has completed a study to assess whether an ownership change has occurred or whether there have been multiple ownership changes since the Company became a “loss corporation” as defined in Section 382. The Company experienced multiple ownership changes occurring in 2005, 2007, 2015, and 2018. The ownership change has and will continue to subject our pre-ownership change net operating loss carryforwards to an annual limitation, which will significantly restrict our ability to use them to offset taxable income in periods following the ownership change. In general, the annual use limitation equals the aggregate value of our stock at the time of the ownership change multiplied by a specified tax-exempt interest rate. As a result of the ownership change, the Company is limited to an approximate $1.7 million annual limitation on our ability to utilize our pre-merger NOL’s and R&D Credits. Due to this limitation, approximately $93.0 million of the $127.1 million pre-merger Federal NOL will expire unutilized as the cumulative limitation amount over a 20 year carryforward period is $34.1 million. Additionally, $4.9 million of Federal R&D Credits will expire unutilized. As a result, in 2019, the Company has reduced its deferred tax assets related to the Federal NOL and Federal R&D Credits by an aggregate of $4.9 million which is offset by the corresponding decrease in the valuation allowance.

The calculation of our tax liabilities involves dealing with uncertainties in the application of complex tax laws and regulations for both federal taxes and the many states in which Rocket operates or does business in. ASC 740 states that a tax benefit from an uncertain tax position may be recognized when it is more likely than not that the position will be sustained upon examination, including resolutions of any related appeals or litigation processes, on the basis of the technical merits.

The Company recorded uncertain tax positions as liabilities in accordance with ASC 740 and adjust these liabilities when our judgment changes as a result of the evaluation of new information not previously available. Because of the complexity of some of these uncertainties, the ultimate resolution may result in a payment that is materially different from our current estimate of the unrecognized tax benefit liabilities. These differences will be reflected as increases or decreases to income tax expense in the period in which new information is available. As of December 31, 2019 the Company has not recorded any uncertain tax positions in its financial statements.

The Company recognizes interest and penalties related to unrecognized tax benefits on the income tax expense line in the accompanying consolidated statement of operations. As of December 31, 2019 and 2018, no accrued interest or penalties are included on the related tax liability line in the consolidated balance sheets.

Commitments and Contingencies

12 Months Ended

Dec. 31, 2019

Commitments and Contingencies [Abstract]

Commitments and Contingencies

13.	Commitments and Contingencies

The Company adopted ASU 2016-02, Leases (“ASU 2016-02”), as amended, on January 1, 2019, which supersedes the prior leasing guidance and upon adoption, requires lessees to recognize right-of-use assets and lease liabilities on the balance sheet for all leases with terms longer than 12 months. Leases are classified as either finance or operating, with classification affecting the pattern of expense recognition in the income statement. Upon the adoption of the guidance, operating leases were capitalized on the balance sheet at the present value of lease payments. The balance sheet amount recorded for existing leases at the date of adoption of ASU 2016-02 was calculated using an estimate of the Company’s collateralized borrowing rate for debt with a similar term.

In adopting ASU 2016-02, the Company elected the available package of practical expedients which allows the Company to not reassess previous accounting conclusions around whether arrangements are or contain leases, the classification of leases, and the treatment of initial direct costs. The Company also made an accounting policy election to utilize the short-term lease exemption, whereby leases with a term of 12 months or less will not follow the recognition and measurement requirements of the new standard. Upon adoption, the Company recognized total right-of-use assets of $2.6 million, with corresponding liabilities of $3.1 million on the 2019 consolidated balance sheets, including the reclassification of $0.5 million from deferred rent to right-of-use assets.

The Company determines if an arrangement is a lease at inception. Operating leases are included in our balance sheet as right-of-use assets from operating leases, current operating lease liabilities and long-term operating lease liabilities. Certain of the Company’s lease agreements contain renewal options; however, the Company does not recognize right-of-use assets or lease liabilities for renewal periods unless it is determined that the Company is reasonably certain of renewing the lease at inception or when a triggering event occurs. As the Company’s leases do not provide an implicit rate, the Company estimated the incremental borrowing rate in calculating the present value of the lease payments. The Company has utilized its incremental borrowing rate based on the long -term borrowing costs of comparable companies in the biotechnology industry. Since the Company elected to account for each lease component and its associated non-lease components as a single combined lease component, all contract consideration was allocated to the combined lease component. Some of the Company’s lease agreements contain rent escalation clauses (including index-based escalations). The Company recognizes the minimum rental expense on a straight-line basis based on the fixed components of a lease arrangement. The Company will amortize this expense over the term of the lease beginning with the lease commencement date. Variable lease components represent amounts that are not fixed in nature and are not tied to an index or rate, and are recognized as incurred.

Operating Leases

Rocket has entered into a lease for a facility in Cranbury, New Jersey, consisting of 103,720 square feet of space including areas for offices, process development, research and development laboratories and 50,000 square feet will be dedicated to AAV Current Good Manufacturing Practice (cGMP) manufacturing to support the Company’s pipeline, which has not yet commenced. A smaller area within this facility was originally leased in August 2018, and the lease was amended in June 2019 to include the full building (such lease, as amended, the “NJ Lease Agreement”). We began to pay rent on September 1, 2019, and the NJ Lease Agreement has a term of 15 years from this date, with an option to renew for two consecutive five-year renewal terms. The NJ Lease Agreement commencement had not yet occurred at December 31, 2019, since the construction of all landlord owned improvements had not been completed, therefore as of December 31, 2019, the right of use asset and lease liability have not been recorded for this lease. These construction costs in progress will be included as part of the right of use asset upon the lease commencement date.

Estimated rent payments for the NJ Lease Agreement are $1.2 million per annum, payable in monthly installments, depending upon the nature of the leased space, and subject to annual base rent increases of 3%. The total commitment under the lease is estimated to be approximately $29.3 million over the 15-year term of the lease. The Company paid a cash security deposit of $0.3 million to the landlord in connection with the NJ Lease Agreement which has been reflected in deposits in the consolidated balance sheets as of December 31, 2019 and 2018. The Company entered into the lease prior to the building being available for use as the building construction was not complete.

The total restricted cash balance for the Company’s operating leases at December 31, 2019 and 2018 was $1.0 million and $0.9 million, respectively.

On March 31, 2016, the Company entered into a lease agreement for its office and laboratory space at the Alexandria Center for Life Sciences in New York, New York with an initial term ending on July 31, 2022 (the “NY Lease Agreement”). In connection with the NY Lease Agreement, the Company established an irrevocable standby letter of credit (“ARE LOC”) with a bank. The ARE LOC, in which the landlord is the beneficiary, serves as the Company’s security deposit on the lease. The Company has a certificate of deposit with a bank as collateral for the ARE LOC which is classified as restricted cash in the consolidated balance sheets. On June 28, 2018, the Company entered into Amendment No.1 to the NY Lease Agreement, whereby the landlord agreed to relieve the Company of its obligations under the lease for a portion of the leased space upon the takeover of the space by a replacement tenant. The Company agreed to extend the lease for the remaining laboratory space by one additional year until July 2022. The Company recorded an additional rent expense of $0.1 million related to the early exit from the lease during the year end December 31, 2018. A replacement tenant has executed a new lease for the office space and as of September 7, 2018, the Company was relieved of its obligations for rent and security deposit for the office space. In October 2018, the Company provided a new letter of credit for $0.08 million (the “New ARE LOC”) relating to the remaining lab space and the existing ARE LOC of $0.2 million was released back to the Company. The New ARE LOC expires and is automatically renewed April 8 of each succeeding calendar year until October 29, 2020, unless written notice is provided no later than 90 days before the then existing expiration date. The Company continues to maintain laboratory space at the Alexandria Center for Life Science facility as its hub for research and development activities.

On June 7, 2018, the Company entered into a three year lease agreement for office space in the Empire State Building (the “ESB Lease Agreement”). In connection with the ESB Lease Agreement, the Company established an irrevocable standby letter of credit (the “Empire LOC”) with a bank for $0.9 million which expires on June 30, 2020 and is renewed automatically for a one year period until its expiration date of July 31, 2021. The Empire LOC serves as the Company’s security deposit on the lease in which the landlord is the beneficiary. The Company has a certificate of deposit of $0.9 million with a bank as collateral for the Empire LOC which is classified as part of restricted cash in the consolidated balance sheets as of December 31, 2019.

On January 4, 2018, in connection with the Reverse Merger, the Company assumed an operating lease for Inotek’s former headquarters in Lexington, Massachusetts, with a term ending in February 2023. In July 2018, the Company signed an agreement to sublease a portion of the Lexington, Massachusetts space and in September 2018, the Company signed an agreement to sublease the remaining portion of the Lexington, Massachusetts space. Rental income received under the sublease agreement totaled $0.3 million and $0.1 million for the years ended December 31, 2019 and 2018, respectively.

Rent expense was $0.9 million and $0.8 million for the years ended December 31, 2019 and 2018, respectively.

Lease cost	December 31, 2019
Operating lease cost	$	1,003
Total lease cost	$	1,003

The following table summarizes the maturity of the Company’s lease liabilities on an undiscounted cash flow basis and a reconciliation to the operating lease liabilities recognized on the Company’s balance sheet as of December 31, 2019:

Maturity of lease liabilities	December 31, 2019
2020		1,103
2021		894
2022		572
2023		73
Total lease payments	$	2,642
Less: interest		(242	)
Total operating lease liabilities	$	2,400

The following disclosure is provided for periods prior to adoption of ASU 2016-02. Future annual minimum lease payment commitments, including the NJ Lease Agreement, as of December 31, 2019 were as follows:

2020		2,742
2021		2,530
2022		2,253
2023		1,802
2024		1,783
Thereafter		20,361
Total	$	31,471

Leases	December 31, 2019

Operating right-of-use assets	$	2,051

Operating current lease liabilities		957
Operating noncurrent lease liabilities		1,443
Total operating lease liabilities	$	2,400

Other information
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	1,088
Weighted-average remaining lease term - operating leases	2.6 years
Weighted-average discount rate - operating leases		7.77	%

Litigation

From time to time, the Company may be subject to various legal proceedings and claims that arise in the ordinary course of its business activities. Although the results of litigation and claims cannot be predicted with certainty, the Company does not believe it is party to any other claim or litigation the outcome of which, if determined adversely to the Company, would individually or in the aggregate be reasonably expected to have a material adverse effect on its business. Regardless of the outcome, litigation can have an adverse impact on the Company because of defense and settlement costs, diversion of management resources and other factors.

Indemnification Arrangements

Pursuant to its bylaws and as permitted under Delaware law, the Company has indemnification obligations to directors, officers, employees or agents of the Company or anyone serving in these capacities. The maximum potential amount of future payments the Company could be required to pay is unlimited. The Company has insurance that reduces its monetary exposure and would enable it to recover a portion of any future amounts paid. As a result, the Company believes that the estimated fair value of these indemnification commitments is minimal.

Throughout the normal course of business, the Company has agreements with vendors that provide goods and services required by the Company to run its business. In some instances, vendor agreements include language that requires the Company to indemnify the vendor from certain damages caused by the Company’s use of the vendor’s goods and/or services. The Company has insurance that would allow it to recover a portion of any future amounts that could arise from these indemnifications. As a result, the Company believes that the estimated fair value of these indemnification commitments is minimal.

Agreements Related to Intellectual Property

12 Months Ended

Dec. 31, 2019

14.	Agreements Related to Intellectual Property

The Company, directly and through its subsidiary Rocket Pharmaceuticals, Ltd. has various license and research and collaboration arrangements. The transactions principally resulted in the acquisition of rights to intellectual property which is in the preclinical phase and has not been tested for safety or feasibility. In all cases, the Company did not acquire tangible assets, processes, protocols or operating systems. The Company expenses the acquired intellectual property rights as of the acquisition date on the basis that the cost of intangible assets purchased from others for use in research and development activities, has no alternative future uses.

Contract Research and Collaboration Agreement with Lund University and J. Richter

In August 2016, Rocket entered into a research and collaboration agreement with Lund University and Johan Richter, M.D., Ph.D. under which Dr. Richter grants to Rocket an exclusive, perpetual, sublicensable, worldwide license to certain intellectual property rights of Dr. Richter relating to lentiviral-mediated gene transfer to treat IMO. In exchange for the license, Rocket is obligated to make an up-front payment, certain clinical and commercial milestone payments, royalty payments (on net sales of products covered by a valid claim within the licensed intellectual property) and sublicense revenue payments to Dr. Richter. Under the terms of the agreement, Lund University and Dr. Richter are obligated to perform contract research for Rocket regarding the use of lentiviral-mediated gene transfer to treat IMO. Intellectual property resulting from the contract research created by Dr. Richter is included in the license described above and also subject to an option for Rocket to purchase ownership of such rights. Intellectual property created by Lund University in conducting such research is non-exclusively licensed to Rocket for non-commercial use and also subject to an option for Rocket to purchase or license such intellectual property under commercially reasonable terms. Rocket is obligated to pay for the contract research according to an agreed budget in quarterly installments in advance.

As consideration for an option to acquire rights from Lund University on commercially reasonable terms and conditions, Rocket paid Lund University an upfront license fee of €0.02 million (approximately $0.02 million), which was expensed as research and development costs. Rocket is obligated to make aggregate milestone payments of up to €0.1 million (approximately $0.1 million) to Lund University and Dr. Richter upon the achievement of specified development and regulatory milestones. With respect to any commercialized products covered by the Lund University agreement, Rocket is obligated to pay a low single digit percentage royalty on net sales, subject to specified adjustments, by Rocket or its sublicensees or affiliates. In the event that Rocket enters into a sublicense agreement with a sublicensee, Rocket will be obligated to pay a portion of any consideration received from such sublicensees in specified circumstances.

The research agreement had an initial term of 24 months. In August 2018, the research and collaboration agreement was amended for an additional year expiring August 2019 and amended in August 2019, renewing for an additional year expiring August 2020.

License Agreement for Danon Disease with UCSD

In February 2017, the Company entered into a License Agreement with The Regents of the University of California, represented by its San Diego campus (“UCSD”), under which UCSD granted us an exclusive, sublicensable, worldwide license to certain intellectual property rights for the treatment of lysosomal storage diseases, including Danon disease. In exchange for the license, the Company became obligated to make an up-front payment, certain clinical and commercial milestone payments, royalty payments (on net sales of products covered by a valid claim within the licensed intellectual property), maintenance fees and sublicense revenue payments.

The upfront license fee of $0.05 million was expensed as research and development costs. The Company is obligated to make aggregate milestone payments of up to $1.5 million to UCSD upon the achievement of specified development and regulatory milestones for the treatment of Danon disease. A reduced schedule of milestone payments applies to achieving the same milestones for additional indications. With respect to any commercialized products covered by the agreement, we are obligated to pay a low single digit percentage royalty on net sales, subject to specified adjustments. If it enters into a sublicense agreement with a sublicensee, it will be obligated to pay a portion of any consideration received from such sublicensees in specified circumstances. The Company is also subject to certain diligence milestones for development of a product using the intellectual property licensed from UCSD under this agreement.

The term of the license agreement with UCSD is through the expiration of the licensed patents, some of which are still in the pending application phase.

REGENXBIO, Inc. License

On November 19, 2018, the Company entered into a license agreement with REGENXBIO Inc. (“RGNX”), pursuant to which the Company obtained an exclusive license for all U.S. patents and patent applications related to RGNX’s NAV AAV-9 vector for the treatment of Danon disease in humans by in vivo gene therapy using AAV-9 to deliver any known LAMP2 transgene isoforms and all possible combinations of LAMP2 transgene isoforms (the “Field”), as well as an exclusive option to license (the “Option Right”) all U.S. patents and patent applications for two additional NAV AAV vectors in the Field (each, a “Licensed Patent” and collectively, the “Licensed Patents”).

Under the terms of the license agreement, the Company is obligated to use commercially reasonable efforts to develop, commercialize, market, promote and sell products incorporating the Licensed Patents (“Licensed Products”). Unless the license agreement is terminated earlier as provided below, the license from RGNX expires on a country-by-country, Licensed Product-by-Licensed Product basis until the later of the expiration date of the last to expire of the last valid claim of the applicable Licensed Patent or ten years after the first commercial sale of a Licensed Product in such country. The license agreement provides that RGNX may terminate the agreement upon a material breach by the Company if the Company does not cure such breach within a specified notice period, if the Company commences a challenge against RGNX or certain of its licensors to declare or render invalid or unenforceable the licensed patents or upon the Company’s bankruptcy or insolvency. The Company may terminate the agreement in its entirety or terminate one or more of the licensed vectors at any time upon six months’ notice. The Company’s Option Right expires four years from the date of the license agreement.

In consideration for the rights granted to the Company under the license agreement, the Company made an upfront payment to RGNX of $7.0 million included as research and development expenses. A fee of $2.0 million per additional vector would be due if the Company exercises its Option Right to purchase additional vectors. The license agreement provides for royalties payable to RGNX in the high-single digits to low-teens on net sales levels of Licensed Products during the royalty term. If successful, the Company will be required to make milestone payments to RGNX of up to $13.0 million for each Licensed Product upon the achievement of specified clinical development and regulatory milestones in the U.S. and European Union. In addition, the Company shall pay RGNX 20% of the payment fees received from a priority review voucher issued in connection with or otherwise related to a Licensed Product. These royalty obligations are subject to specified reductions if additional licenses from third parties are required. The Company must also pay RGNX a portion of all non-royalty sublicense income (if any) received from sublicensees. The Company paid a $1.0 million license fee payment under the RGNX agreement upon the dosing of the first Danon patient in 2019.

Strategic Research Collaboration

12 Months Ended

Dec. 31, 2019

Strategic Research Collaboration [Abstract]

Strategic Research Collaboration

15.	Strategic Research Collaboration

On May 16, 2018, Rocket and the Stanford University School of Medicine (“Stanford University”) entered into a strategic collaboration to support the advancement of FA and PKD gene therapy research. Under the terms of the collaboration agreement, Stanford University will serve as the lead clinical trial research center in the U.S. for the planned FA registrational trial and would also be the lead U.S. site for PKD clinical trials. The project will also separately evaluate the potential for non-myeloablative, non-genotoxic antibody-based conditioning regimens as a future development possibility that may be applied across bone marrow-derived disorders. In addition, Rocket agreed to support expansion of Stanford University’s Laboratory for Cell and Gene Therapy (“LCGM”) in efforts to further enhance the development of Rocket’s internal pipeline. Rocket agreed to fund up to $3.5 million for the LCGM expansion upon which 40% or $1.4 million was due upon execution of the agreement and the balance is due upon the achievement of certain milestones. $1.4 million of the $3.5 million milestone payments was paid during the year ended December 31, 2019. In January 2019, the Company and Stanford signed a Clinical Trial Agreement for the treatment of FA. Upon the signing of the January 2019 Stanford Clinical Trial Agreement, the second milestone of $1.4 million for the LGCM became due and was expensed in January 2019, when the milestone was met. As of December 31, 2019, none of the remaining milestones were met with regard to the LCGM.

CIRM Grant

12 Months Ended

Dec. 31, 2019

CIRM Grant [Abstract]

CIRM Grant

16.	CIRM Grant

On April 30, 2019, the CIRM awarded Rocket up to $6.5 million under a CLIN2 grant award to support the clinical development of gene therapy for LAD-I. Proceeds from the grant will help fund clinical trial costs as well as manufactured drug product for Phase I/II patients enrolled at the U.S. clinical site, University of California, Los Angeles (“UCLA”) Mattel Children’s Hospital, led by principal investigator Donald Kohn, M.D., UCLA Professor of Microbiology, Immunology and Molecular Genetics, Pediatrics (Hematology/Oncology), Molecular and Medical Pharmacology and member of the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research at UCLA. On July 1, 2019, we received the first grant from CIRM of $0.8 million and on October 15, 2019, we received the second grant of $0.4 million, based on eligible costs incurred under the grant. The CIRM grant reimbursements are accrued as an offset against R&D expenses as reimbursable expenses are incurred.

Related Party Transactions

12 Months Ended

Dec. 31, 2019

Related Party Transactions

17.	Related Party Transactions

During March 2018, the Company entered into a consulting agreement with a member of the Board of Directors for strategic and finance consulting services to be provided to the Company. The Company incurred expenses of $3,600 and $0.2 million in connection with this consulting agreement for the years ended December 31, 2019 and 2018, respectively.

During April 2018, the Company entered into a consulting agreement with a different member of the Board of Directors for business development consulting services. The Company incurred expenses of $0.1 million in connection with this consulting agreement for both of the years ended December 31, 2019 and 2018.

401(k) Savings Plan

12 Months Ended

Dec. 31, 2019

401(k) Savings Plan [Abstract]

401(k) Savings Plan

18.	401(k) Savings Plan

The Company has a defined contribution savings plan (the “Plan”) under Section 401(k) of the Internal Revenue Code of 1986. This Plan covers substantially all employees who meet minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pre-tax basis. Company contributions to the Plan may be made at the discretion of the Company’s board of directors. The Company has elected to match 4% of employee contributions to the Plan, subject to certain limitations. The Company’s matching contribution for the years ended December 31, 2019 and 2018, was $0.2 million and $0.1 million, respectively.

Subsequent Events

12 Months Ended

Dec. 31, 2019

Subsequent Events [Abstract]

Subsequent Events

19.	Subsequent Events

Convertible Notes Exchange Agreement

On February 10, 2020, the Company entered into separate, privately negotiated exchange agreements (the “Exchange Agreements”) with certain holders of its outstanding 5.75% Convertible Senior Notes due 2021 (the “Old Notes”) (see Note 8). Pursuant to the Exchange Agreements, we exchanged approximately $39.4 million aggregate principal amount of the Old Notes (which represents approximately 76% of the aggregate outstanding principal amount of the Old Notes) for (a) approximately $39.4 million aggregate principal amount of 6.25% Convertible Senior Notes due 2022 (the “New Notes”) (an exchange ratio equal to 1.00 New Notes per exchanged Old Note) and (b) $119,416 in cash to pay the accrued and unpaid interest on the exchanged Old Notes from, and including, February 1, 2020, to, but excluding, the closing date of the exchange transactions. The New Notes were issued in private placements exempt from registration in reliance on Section 4(a) (2) of the Securities Act of 1933, as amended (the “Securities Act”). Upon completion of the exchange transactions, approximately $12.7 million aggregate principal amount of Old Notes remained outstanding. The exchange transactions closed on February 20, 2020.

The conversion rate for the New Notes will initially be 31.1876 shares of the Company’s common stock per $1,000 principal amount of 2022 Notes, which is equivalent to an initial conversion price of approximately $32.06 per share of common stock, and is subject to adjustment under the terms of the New Notes. The Company may redeem for cash all or any portion of the 2022 Notes, at its option, if the last reported sale price of its common stock is equal to or greater than 130% of the conversion price then in effect for at least 20 trading days (whether or not consecutive) during any 30 consecutive trading day period (including the last trading day of such period) ending within the five trading days immediately preceding the date on which the Company provides written notice of redemption. The 2022 Notes Indenture contains customary terms and covenants and events of default. We are currently reviewing the accounting for this transaction.

Additionally, the Company repurchased 3,000 shares of its common stock at an aggregate amount of $71,670 from certain holders of the Old Notes participating in the exchange transactions in privately negotiated, private transactions.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2019

Summary of Significant Accounting Policies [Abstract]

Principles of Consolidation

Use of Estimates

Cash, Cash Equivalents and Restricted Cash

	December 31, 2019		December 31, 2018

Cash and cash equivalents	$	185,383	$	111,355
Restricted cash		1,525		1,436
	$	186,908	$	112,791

Government Grants

Concentrations of Credit Risk and Off-balance Sheet Risk

Concentrations of credit risk and off-balance sheet risk

Investments

Goodwill

Property and Equipment

Internal Use Software

Impairment of Long-Lived Assets

Fair Value Measurements

Level 1—Valuations based on unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date.

Level 2—Valuations based on quoted prices for similar assets or liabilities in markets that are not active or for which all significant inputs are observable, either directly or indirectly.

Level 3—Valuations that require inputs that reflect the Company’s own assumptions that are both significant to the fair value measurement and unobservable.

Research and Development

Foreign Currency Transactions

Treasury Stock

The Company records treasury stock at cost.

Stock-Based Compensation

The Company recognizes compensation expense for at least the portion of awards that are vested. Forfeitures are accounted for as they occur.

NYC Biotechnology Tax Credit Program

Recent Accounting Pronouncements

Other than the adoption of ASU 2016-02 (see Note 13), there were no other recent accounting standards that impacted the Company for the year ended December 31, 2019.

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2019

Summary of Significant Accounting Policies [Abstract]

Cash, Cash Equivalents and Restricted Cash

	December 31, 2019		December 31, 2018

Cash and cash equivalents	$	185,383	$	111,355
Restricted cash		1,525		1,436
	$	186,908	$	112,791

2018 Reverse-Merger Acquisition Accounting (Tables)

12 Months Ended

Dec. 31, 2019

2018 Reverse-Merger Acquisition Accounting [Abstract]

Acquisition-date Fair Value of Consideration

The acquisition-date fair value of the consideration transferred is as follows:

Number of shares of the combined company owned by Inotek shareholders		6,805,608
Number of shares issuable in connection with fully vested RSUs of Inotek immediately prior to the Reverse Merger		271,718
Inotek common stock on the acquisition date		7,077,326
Price per share of Inotek common stock on acquisition date	$	12.16
Total purchase price	$	86,060

Recognized Identified Assets Acquired and Liabilities Assumed

Cash and cash equivalents	$	76,348
Short term investments		21,292
Prepaid expense and other assets		1,041
Property and equipment		256
Deposits		168
Goodwill		30,815
Accounts payable and accrued expenses		(4,961	)
Convertible notes		(38,388	)
Unfavorable lease liability		(511	)
Net assets acquired	$	86,060

Fair Value of Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2019

Fair Value of Financial Instruments [Abstract]

Fair Value of Financial Instruments Measured on Recurring Basis

	Fair Value Measurements as of December 31, 2019 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Money market mutual funds (included in cash and cash equivalents)	$	72,114	$	-	$	-	$	72,114
Cash		7,542		-		-		7,542
		79,656		-		-		79,656

United States Treasury securities		75,464		-		-		75,464
Government Bonds		-		8,000		-		8,000
Corporate Bonds		-		29,268		-		29,268
Municipal Bonds		-		6,000		-		6,000
Investments		75,464		43,268		-		118,732

	$	155,120	$	43,268	$	-	$	198,388

	Fair Value Measurements as of
	December 31, 2018 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Money market mutual funds (included in cash and cash equivalents)	$	30,552	$	-	$	-	$	30,552

United States Treasury securities		101,777		-		-		101,777
Investments		101,777		-		-		101,777

	$	132,329	$	-	$	-	$	132,329

Property and Equipment (Tables)

12 Months Ended

Dec. 31, 2019

Property and Equipment [Abstract]

Property and Equipment

The Company’s property and equipment consisted of the following:

	December 31, 2019			December 31, 2018
Laboratory equipment	$	1,910		$	1,556
Computer equipment		179			179
Furniture and fixtures		273			273
Leasehold improvements		29			29
Construction costs in progress		27,809			469
		30,200			2,506
Less: accumulated depreciation		(905	)		(479	)
	$	29,295		$	2,027

Accounts Payable and Accrued Expenses (Tables)

12 Months Ended

Dec. 31, 2019

Accounts Payable and Accrued Expenses [Abstract]

Accounts Payable and Accrued Expenses

At December 31, 2019 and 2018, the Company’s accounts payable and accrued expenses consisted of the following:

	December 31, 2019		December 31, 2018
Research and development	$	7,418	$	10,414
Construction costs in progress		4,424		-
Bonus		2,459		1,774
Accrued interest		1,241		1,241
Government grant payable		562		534
Professional fees		553		690
Accrued vacation		129		123
Severance and benefits		-		7
Internal use software		226		-
Other		340		589
	$	17,352	$	15,372

2021 Convertible Notes Payable (Tables)

12 Months Ended

Dec. 31, 2019

2021 Convertible Notes Payable [Abstract]

Carrying Value of Convertible Notes

The table below summarizes the carrying value of the 2021 Convertible Notes:

	December 31, 2019			December 31, 2018

Principal amount	$	52,000		$	52,000
Discount		(6,951	)		(10,553	)
Carrying value	$	45,049		$	41,447

Stock-Based Awards (Tables)

12 Months Ended

Dec. 31, 2019

Stock-Based Awards [Abstract]

Weighted-Average Assumptions for Stock Options

	Years Ended December 31,
	2019			2018

Risk-free interest rate		2.26	%		2.64	%
Expected term (in years)		5.81			5.85
Expected volatility		75.71	%		87.70	%
Expected dividend yield		0.00	%		0.00	%
Exercise price	$	14.47		$	17.82
Fair value of common stock	$	14.47		$	17.98

Stock Option Activity

The following table summarizes stock option activity for the years ended December 31, 2019 and 2018, under the Revised 2014 Plan:

	Number of Shares			Weighted Average Exercise Price		Weighted Average Contractual Term (Years)		Aggregate Intrinsic Value

Outstanding as of December 31, 2017		6,959,347		$	1.06		8.17	$	27,175
Assumed as part of merger with Inotek		523,456			2.01		6.78
Granted		1,650,878			17.82		9.26
Exercised		(370,753	)		1.27		-
Forfeited		(146,931	)		3.02
Outstanding as of December 31, 2018		8,615,997		$	4.48		7.51	$	94,474
Granted		1,706,116			14.47		9.29
Exercised		(110,325	)		2.31				1,429
Cancelled		(448,247	)		10.83
Outstanding as of December 31, 2019		9,763,541		$	5.96		6.96		164,021


Options vested and exercisable as of December 31, 2019		7,307,751		$	3.06		6.30	$	143,996
Options unvested as of December 31, 2019		2,455,790		$	14.61		8.91

Stock-Based Compensation Expense

Stock-Based Compensation

	Year Ended December 31,
	2019		2018

Research and development	$	6,153	$	7,375
General and administrative		7,218		6,226
Total	$	13,371	$	13,601

Net Loss Per Share (Tables)

12 Months Ended

Dec. 31, 2019

Net Loss Per Share [Abstract]

Basic and Diluted Net Loss Per Share

Basic and diluted net loss per share attributable to common stockholders was calculated as follows:

	For the Years Ended December 31,
	2019			2018

Numerator:
Net loss attributable to common stockholders	$	(77,270	)	$	(74,518	)
Denominator:
Weighted-average common shares outstanding - basic and diluted		49,010,358			39,377,666
Net loss per share attributable to common stockholders - basic and diluted	$	(1.58	)	$	(1.89	)

Antidilutive Securities Excluded from Computation of Diluted Net Loss Per Share

	For the Years Ended December 31,
	2019		2018
Shares issuable upon conversion of the 2021 Convertible Notes		1,620,948		1,620,948
Warrants exercisable for common shares		14,102		14,102
Options to purchase common shares		9,763,541		8,615,997
		11,398,591		10,251,047

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2019

Income Taxes [Abstract]

Reconciliation of Income Tax Benefit Computed at Statutory Federal Income Tax Rate to Income Taxes

A reconciliation of income tax benefit computed at the statutory federal income tax rate to income taxes as reflected in the financial statements is as follows:

	For the years ended December 31,
	2019			2018
U.S. federal tax at statutory rate		21.0%			21.0%
Change in state tax apportionment		(17.4%	)		15.8%
Stock compensation		(0.7%	)		0.0%
Section 382 limitation		0.0%			(38.7%	)
Valuation allowance		(5.1%	)		3.5%
Other		2.1%			(1.6%	)
Effective tax rate		0%			0%

Deferred Tax Assets and Liabilities

The significant components of the Company’s deferred income tax assets and liabilities after applying the enacted corporate tax rates are as follows:

	For the years ended December 31,
	2019			2018
Deferred income tax assets (liabilities)
Net operating losses (“NOL”) and credit carryforwards	$	20,988		$	28,400
Capitalized research and development costs		27,652			17,098
Other		643			1,385
Stock-based compensation		3,896			4,563
Debt discount		(1,460	)		(3,652	)
Valuation allowance		(51,719	)		(47,794	)
Net deferred income tax asset	$	-		$	-

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2019

Commitments and Contingencies [Abstract]

Lease Cost

Rent expense was $0.9 million and $0.8 million for the years ended December 31, 2019 and 2018, respectively.

Lease cost	December 31, 2019
Operating lease cost	$	1,003
Total lease cost	$	1,003

Maturities of Lease Liabilities

Maturity of lease liabilities	December 31, 2019
2020		1,103
2021		894
2022		572
2023		73
Total lease payments	$	2,642
Less: interest		(242	)
Total operating lease liabilities	$	2,400

Remaining Aggregate Annual Commitments

2020		2,742
2021		2,530
2022		2,253
2023		1,802
2024		1,783
Thereafter		20,361
Total	$	31,471

Operating lease Assets and Liabilities

Leases	December 31, 2019

Operating right-of-use assets	$	2,051

Operating current lease liabilities		957
Operating noncurrent lease liabilities		1,443
Total operating lease liabilities	$	2,400

Other Information

Other information
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	1,088
Weighted-average remaining lease term - operating leases	2.6 years
Weighted-average discount rate - operating leases		7.77	%

Nature of Business and Basis of Presentation (Details)	12 Months Ended
Nature of Business and Basis of Presentation (Details)	Dec. 31, 2019 Program
Nature of Business and Basis of Presentation [Abstract]
Number of clinical-stage programs currently enrolling patients	3

Risks and Liquidity (Details) - USD ($) $ in Thousands					12 Months Ended
Risks and Liquidity (Details) - USD ($) $ in Thousands	Dec. 10, 2019	Apr. 18, 2019	Nov. 30, 2018	Jan. 26, 2018	Dec. 31, 2019	Dec. 31, 2018
Risks and Liquidity [Abstract]
Accumulated deficit					$ (183,143)	$ (105,873)
Cash, cash equivalents and investments					$ 304,100
Common Stock [Member]
Shareholders' Equity Disclosure [Abstract]
Common stock shares issued (in shares)					9,568,000	11,475,242
IPO [Member] \| Common Stock [Member]
Shareholders' Equity Disclosure [Abstract]
Net proceeds, offering amount	$ 91,700	$ 86,100	$ 59,300	$ 78,500	$ 177,800
Common stock shares issued (in shares)	4,393,000	5,175,000	4,082,500	6,325,000

Summary of Significant Accounting Policies (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) Segment	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Cash, Cash Equivalents and Restricted Cash [Abstract]
Cash and cash equivalents	$ 185,383	$ 111,355
Restricted cash	1,525	1,436
Total	186,908	112,791	$ 18,349
Government Grants [Abstract]
Receivable of offset grants against expenses	1,200
Investments [Abstract]
Realized gains (losses) on investment	0	0
Net unrealized gain (loss) on investments	$ 147	(127)
Goodwill [Abstract]
Number of operating segment \| Segment	1
Number of reporting unit \| Segment	1
Goodwill impairment	$ 0	0
Impairment of Long-Lived Assets [Abstract]
Impairment of long-lived assets	0	0
NYC Biotechnology Tax Credit Program [Abstract]
Research and development incentive income	$ 300	$ 200
Minimum [Member]
Property and Equipment [Abstract]
Estimated useful lives	3 years
Maximum [Member]
Property and Equipment [Abstract]
Estimated useful lives	15 years
2021 Convertible Notes [Member]
Fair Value Measurements [Abstract]
Fair value convertible note	$ 54,500

2018 Reverse-Merger Acquisition Accounting (Details) - USD ($) $ / shares in Units, $ in Thousands	Jan. 04, 2018	Dec. 31, 2019	Dec. 31, 2018
Estimated Fair Values of Assets Acquired and Liabilities Assumed [Abstract]
Goodwill		$ 30,815	$ 30,815
Inotek [Member]
Acquisition-date Fair Value of Consideration Transferred [Abstract]
Number of shares issuable - consideration transferred (in shares)	7,077,326
Price per share of Inotek common stock on acquisition date (in dollars per share)	$ 12.16
Total purchase price	$ 86,060
Estimated Fair Values of Assets Acquired and Liabilities Assumed [Abstract]
Cash and cash equivalents	76,348
Short-term investments	21,292
Prepaid expense and other assets	1,041
Property and equipment	256
Deposits	168
Goodwill	30,815
Accounts payable and accrued expenses	(4,961)
Convertible notes	(38,388)
Unfavorable lease liability	(511)
Net assets acquired	$ 86,060
Inotek [Member] \| Restricted Stock Units [Member]
Acquisition-date Fair Value of Consideration Transferred [Abstract]
Number of shares issuable - consideration transferred (in shares)	271,718
Inotek [Member] \| Common Stock [Member]
Acquisition-date Fair Value of Consideration Transferred [Abstract]
Number of shares issuable - consideration transferred (in shares)	6,805,608

Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
2021 Convertible Notes [Member]
Additional Information in Fair Value Disclosure [Abstract]
Fair value convertible note	$ 54,500
Recurring [Member]
Assets [Abstract]
Cash and cash equivalents	79,656
Fair value of financial instruments		$ 132,329
Recurring [Member] \| Short-term Investments [Member]
Assets [Abstract]
Fair value of financial instruments	198,388
Recurring [Member] \| Money Market Mutual Funds [Member]
Assets [Abstract]
Cash and cash equivalents	72,114	30,552
Recurring [Member] \| Cash [Member]
Assets [Abstract]
Cash and cash equivalents	7,542
Recurring [Member] \| United States Treasury Securities [Member]
Assets [Abstract]
Investments		101,777
Recurring [Member] \| United States Treasury Securities [Member] \| Short-term Investments [Member]
Assets [Abstract]
Fair value of financial instruments	75,464
Recurring [Member] \| Government Bonds [Member] \| Short-term Investments [Member]
Assets [Abstract]
Fair value of financial instruments	8,000
Recurring [Member] \| Corporate Bonds [Member] \| Short-term Investments [Member]
Assets [Abstract]
Fair value of financial instruments	29,268
Recurring [Member] \| Municipal Bonds [Member] \| Short-term Investments [Member]
Assets [Abstract]
Fair value of financial instruments	6,000
Recurring [Member] \| Investments [Member]
Assets [Abstract]
Investments		101,777
Recurring [Member] \| Investments [Member] \| Short-term Investments [Member]
Assets [Abstract]
Investments	118,732
Recurring [Member] \| Level 1 [Member]
Assets [Abstract]
Cash and cash equivalents	79,656
Fair value of financial instruments		132,329
Recurring [Member] \| Level 1 [Member] \| Short-term Investments [Member]
Assets [Abstract]
Fair value of financial instruments	155,120
Recurring [Member] \| Level 1 [Member] \| Money Market Mutual Funds [Member]
Assets [Abstract]
Cash and cash equivalents	72,114	30,552
Recurring [Member] \| Level 1 [Member] \| Cash [Member]
Assets [Abstract]
Cash and cash equivalents	7,542
Recurring [Member] \| Level 1 [Member] \| United States Treasury Securities [Member]
Assets [Abstract]
Investments		101,777
Recurring [Member] \| Level 1 [Member] \| United States Treasury Securities [Member] \| Short-term Investments [Member]
Assets [Abstract]
Fair value of financial instruments	75,464
Recurring [Member] \| Level 1 [Member] \| Government Bonds [Member] \| Short-term Investments [Member]
Assets [Abstract]
Fair value of financial instruments	0
Recurring [Member] \| Level 1 [Member] \| Corporate Bonds [Member] \| Short-term Investments [Member]
Assets [Abstract]
Fair value of financial instruments	0
Recurring [Member] \| Level 1 [Member] \| Municipal Bonds [Member] \| Short-term Investments [Member]
Assets [Abstract]
Fair value of financial instruments	0
Recurring [Member] \| Level 1 [Member] \| Investments [Member]
Assets [Abstract]
Investments		101,777
Recurring [Member] \| Level 1 [Member] \| Investments [Member] \| Short-term Investments [Member]
Assets [Abstract]
Investments	75,464
Recurring [Member] \| Level 2 [Member]
Assets [Abstract]
Cash and cash equivalents	0
Fair value of financial instruments		0
Recurring [Member] \| Level 2 [Member] \| Short-term Investments [Member]
Assets [Abstract]
Fair value of financial instruments	43,268
Recurring [Member] \| Level 2 [Member] \| Money Market Mutual Funds [Member]
Assets [Abstract]
Cash and cash equivalents	0	0
Recurring [Member] \| Level 2 [Member] \| Cash [Member]
Assets [Abstract]
Cash and cash equivalents	0
Recurring [Member] \| Level 2 [Member] \| United States Treasury Securities [Member]
Assets [Abstract]
Investments		0
Recurring [Member] \| Level 2 [Member] \| United States Treasury Securities [Member] \| Short-term Investments [Member]
Assets [Abstract]
Fair value of financial instruments	0
Recurring [Member] \| Level 2 [Member] \| Government Bonds [Member] \| Short-term Investments [Member]
Assets [Abstract]
Fair value of financial instruments	8,000
Recurring [Member] \| Level 2 [Member] \| Corporate Bonds [Member] \| Short-term Investments [Member]
Assets [Abstract]
Fair value of financial instruments	29,268
Recurring [Member] \| Level 2 [Member] \| Municipal Bonds [Member] \| Short-term Investments [Member]
Assets [Abstract]
Fair value of financial instruments	6,000
Recurring [Member] \| Level 2 [Member] \| Investments [Member]
Assets [Abstract]
Investments		0
Recurring [Member] \| Level 2 [Member] \| Investments [Member] \| Short-term Investments [Member]
Assets [Abstract]
Investments	43,268
Recurring [Member] \| Level 3 [Member]
Assets [Abstract]
Cash and cash equivalents	0
Fair value of financial instruments		0
Recurring [Member] \| Level 3 [Member] \| Short-term Investments [Member]
Assets [Abstract]
Fair value of financial instruments	0
Recurring [Member] \| Level 3 [Member] \| Money Market Mutual Funds [Member]
Assets [Abstract]
Cash and cash equivalents	0	0
Recurring [Member] \| Level 3 [Member] \| Cash [Member]
Assets [Abstract]
Cash and cash equivalents	0
Recurring [Member] \| Level 3 [Member] \| United States Treasury Securities [Member]
Assets [Abstract]
Investments		0
Recurring [Member] \| Level 3 [Member] \| United States Treasury Securities [Member] \| Short-term Investments [Member]
Assets [Abstract]
Fair value of financial instruments	0
Recurring [Member] \| Level 3 [Member] \| Government Bonds [Member] \| Short-term Investments [Member]
Assets [Abstract]
Fair value of financial instruments	0
Recurring [Member] \| Level 3 [Member] \| Corporate Bonds [Member] \| Short-term Investments [Member]
Assets [Abstract]
Fair value of financial instruments	0
Recurring [Member] \| Level 3 [Member] \| Municipal Bonds [Member] \| Short-term Investments [Member]
Assets [Abstract]
Fair value of financial instruments	0
Recurring [Member] \| Level 3 [Member] \| Investments [Member]
Assets [Abstract]
Investments		$ 0
Recurring [Member] \| Level 3 [Member] \| Investments [Member] \| Short-term Investments [Member]
Assets [Abstract]
Investments	$ 0

Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property and Equipment [Abstract]
Property and equipment, gross	$ 30,200	$ 2,506
Less: accumulated depreciation	(905)	(479)
Property and equipment, net	29,295	2,027
Depreciation expense	426	330
Laboratory Equipment [Member]
Property and Equipment [Abstract]
Property and equipment, gross	1,910	1,556
Computer Equipment [Member]
Property and Equipment [Abstract]
Property and equipment, gross	179	179
Furniture and Fixtures [Member]
Property and Equipment [Abstract]
Property and equipment, gross	273	273
Leasehold Improvements [Member]
Property and Equipment [Abstract]
Property and equipment, gross	29	29
Construction Costs in Progress [Member]
Property and Equipment [Abstract]
Property and equipment, gross	27,809	469
Capitalized interest	$ 700	$ 0

Accounts Payable and Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accounts Payable and Accrued Expenses [Abstract]
Research and development	$ 7,418	$ 10,414
Construction costs in progress	4,424	0
Bonus	2,459	1,774
Accrued interest	1,241	1,241
Government grant payable	562	534
Professional fees	553	690
Accrued vacation	129	123
Severance and benefits	0	7
Internal use software	226	0
Other	340	589
Total	$ 17,352	$ 15,372

2021 Convertible Notes Payable (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Debt [Abstract]
Accretion of debt discount	$ 3,602	$ 3,059
Carrying value of convertible notes [Abstract]
Carrying value	$ 45,049	41,447
2021 Convertible Notes [Member]
Debt [Abstract]
Debt instrument maturity date	Aug. 01, 2021
Convertible senior notes, interest rate, stated percentage	5.75%
Conversion ratio	31.1876
Conversion price (in dollars per share)	$ 32.08
Conversion per principal amount of debt	$ 1
Percentage of common stock conversion price	200.00%
Number of trading days immediately preceding notice of redemption	5 days
Redemption price percentage	100.00%
Percentage of convertible notes due and payable in event of default	100.00%
Debt instrument, additional interest in the event of default for first 90 Days	0.25%
Debt instrument, additional interest in the event of default between 91st Day to 180th Day	0.50%
Effective interest rate	15.30%
Accretion of debt discount	$ 3,601	3,059
Carrying value of convertible notes [Abstract]
Principal amount	52,000	52,000
Discount	(6,951)	(10,553)
Carrying value	$ 45,049	$ 41,447
2021 Convertible Notes [Member] \| Minimum [Member]
Debt [Abstract]
Conversion ratio	0
Stock price considered for conversion rate (in dollars per share)	$ 26.72
Percentage holders of principal amount of debt	25.00%
2021 Convertible Notes [Member] \| Maximum [Member]
Debt [Abstract]
Conversion ratio	6.2375
Stock price considered for conversion rate (in dollars per share)	$ 160.00

Shareholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands							1 Months Ended		12 Months Ended
	Dec. 10, 2019	Apr. 18, 2019	Jan. 02, 2019	Dec. 28, 2018	Nov. 30, 2018	Jan. 26, 2018	Nov. 30, 2019	Jan. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Jun. 25, 2019
Shareholders' Equity Disclosure [Abstract]
Shares repurchased									$ 726	$ 668
Treasury stock									(53)	(668)
Retirement of treasury stock									0
Proceeds from sale of treasury stock							$ 300		344	0
Gross proceeds, offering amount									$ 177,760	$ 154,022
Common Stock [Member]
Shareholders' Equity Disclosure [Abstract]
Shares repurchase (in shares)									0	0
Shares repurchased									$ 0	$ 0
Number of shares settled (in shares)			50,000							50,000
Average price of shares (in dollars per share)			$ 14.50							$ 13.36
Prepaid Expense										$ 700
Number of treasury stock retired (in shares)								100,000	100,000
Retirement of treasury stock									$ (1)
Common stock shares issued (in shares)									9,568,000	11,475,242
Common Stock [Member] \| RTW Investments, LP [Member]
Shareholders' Equity Disclosure [Abstract]
Common stock shares issued (in shares)										100,000
Share price (in dollars per share)										$ 13.93
Gross proceeds, offering amount										$ 1,400
Common Stock [Member] \| IPO [Member]
Shareholders' Equity Disclosure [Abstract]
Common stock shares issued (in shares)	4,393,000	5,175,000			4,082,500	6,325,000
Number of shares issued from the exercise of the underwriters' option (in shares)	573,000	675,000			532,500	825,000
Share price (in dollars per share)	$ 22.25	$ 17.50			$ 15.50	$ 13.25
Gross proceeds, offering amount	$ 99,700	$ 90,600			$ 63,300	$ 83,800
Offering costs	6,100	4,500			4,000	5,300
Net proceeds, offering amount	$ 91,700	$ 86,100			$ 59,300	$ 78,500			$ 177,800
Common Stock [Member] \| Private Placement [Member]
Shareholders' Equity Disclosure [Abstract]
Common stock shares issued (in shares)					967,742
Share price (in dollars per share)					$ 15.50
Gross proceeds, offering amount					$ 15,000
Offering costs					200
Net proceeds, offering amount					$ 14,800
Treasury Stock [Member]
Shareholders' Equity Disclosure [Abstract]
Shares repurchase (in shares)				100,000
Shares repurchased				$ 1,400					725	668
Treasury stock			$ (700)						(100)		$ (300)
Retirement of treasury stock									1,393
Additional Paid in Capital [Member]
Shareholders' Equity Disclosure [Abstract]
Shares repurchased									1	$ 0
Retirement of treasury stock								$ (1,300)	$ (1,392)

Stock-Based Awards, Stock Option Valuation (Details) - Stock Options [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Stock Option Activity [Roll Forward]
Outstanding at beginning of period (in shares)	8,615,997	6,959,347
Assumed as part of merger (in shares)		523,456
Granted (in shares)	1,706,116	1,650,878
Exercised (in shares)	(110,325)	(370,753)
Forfeited/Cancelled (in shares)	(448,247)	(146,931)
Outstanding at end of period (in shares)	9,763,541	8,615,997	6,959,347
Options vested and exercisable at end of period (in shares)	7,307,751
Options unvested at end of period (in shares)	2,455,790
Weighted Average Exercise Price [Abstract]
Outstanding at beginning of period (in dollars per share)	$ 4.48	$ 1.06
Assumed as part of merger (in dollars per share)		2.01
Granted (in dollars per share)	14.47	17.82
Exercised (in dollars per share)	2.31	1.27
Forfeited/Cancelled (in dollars per share)	10.83	3.02
Outstanding at end of period (in dollars per share)	5.96	$ 4.48	$ 1.06
Options vested and exercisable at end of period (in dollars per share)	3.06
Options unvested at end of period (in dollars per share)	$ 14.61
Weighted-Average Remaining Contractual Term [Abstract]
Outstanding	6 years 11 months 16 days	7 years 6 months 4 days	8 years 2 months 1 day
Assumed as part of merger		6 years 9 months 11 days
Granted	9 years 3 months 14 days	9 years 3 months 4 days
Exercised		0 years
Options vested and exercisable	6 years 3 months 18 days
Options unvested	8 years 10 months 28 days
Aggregate Intrinsic Value [Abstract]
Outstanding at beginning of period	$ 94,474	$ 27,175
Exercised	1,429
Outstanding at end of period	164,021	$ 94,474	$ 27,175
Options vested and exercisable	$ 143,996
Weighted average grant date fair value of shares granted (in dollars per share)	$ 9.58	$ 13.21
Total fair value of options vested	$ 63,100	$ 91,300
Employees and Directors [Member]
Weighted-Average Assumptions [Abstract]
Risk-free interest rate	2.26%	2.64%
Expected term	5 years 9 months 22 days	5 years 10 months 6 days
Expected volatility	75.71%	87.70%
Expected dividend yield	0.00%	0.00%
Exercise price (in dollars per share)	$ 14.47	$ 17.82
Fair value of common stock (in dollars per share)	$ 14.47	$ 17.98

Stock-Based Awards, Stock-Based Compensation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Stock-Based Compensation [Abstract]
Stock-based compensation expense	$ 13,371	$ 13,601
Unrecognized share-based compensation cost	$ 19,300
Weighted average period expected to recognize unrecognized share-based compensation cost	1 year 8 months 26 days
Research and Development [Member]
Stock-Based Compensation [Abstract]
Stock-based compensation expense	$ 6,153	7,375
General and Administrative [Member]
Stock-Based Compensation [Abstract]
Stock-based compensation expense	$ 7,218	$ 6,226

Net Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Numerator [Abstract]
Net loss attributable to common stockholders	$ (77,270)	$ (74,518)
Denominator [Abstract]
Weighted-average common shares outstanding - basic and diluted (in shares)	49,010,358	39,377,666
Net loss per share attributable to common stockholders - basic and diluted (in dollars per share)	$ (1.58)	$ (1.89)
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Securities excluded from computation of diluted net loss per share (in shares)	11,376,283	26,232,483
Shares Issuable upon Conversion of the 2021 Convertible Notes [Member]
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Securities excluded from computation of diluted net loss per share (in shares)	1,620,948	1,620,948
Warrants Exercisable for Common Shares [Member]
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Securities excluded from computation of diluted net loss per share (in shares)	14,102	14,102
Warrants outstanding (in shares)	14,102	14,102
Exercise price of warrants (in dollars per share)	$ 24.82	$ 24.82
Warrants expiry date	Jun. 28, 2023
Options to Purchase Common Shares [Member]
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Securities excluded from computation of diluted net loss per share (in shares)	9,741,233	8,615,997

Income Taxes, Net Loss by Jurisdiction (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Domestic [Member]
Details of Income Taxes [Abstract]
Provision for income taxes	$ 0	$ 0
State [Member]
Details of Income Taxes [Abstract]
Provision for income taxes	$ 0	$ 0

Income Taxes, Reconciliation Between Effective Tax Rates and Statutory Rates (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of Income Tax Benefit Computed at Statutory Federal Income Tax Rate to Income Taxes [Abstract]
U.S. federal tax at statutory rate	21.00%	21.00%
Change in state tax apportionment	(17.40%)	15.80%
Stock Compensation	(0.70%)	0.00%
Section 382 limitation	0.00%	(38.70%)
Valuation allowance	(5.10%)	3.50%
Other	2.10%	(1.60%)
Effective tax rate	0.00%	0.00%

Income Taxes, Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Deferred income tax assets (liabilities) [Abstract]
Net operating losses ("NOL") and credit carryforwards	$ 20,988	$ 28,400
Capitalized research and development costs	27,652	17,098
Other	643	1,385
Stock-based compensation	3,896	4,563
Debt discount	(1,460)	(3,652)
Valuation allowance	(51,719)	(47,794)
Net deferred income tax asset	$ 0	$ 0

Income Taxes, NOL Carryforwards and Tax Credits (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Loss Carryforwards [Abstract]
Increase in valuation allowance	$ 3.9	$ 46.6
Annual limitations under section 382 of IRC	1.7
Uncertain Tax Positions [Abstract]
Uncertain tax positions	0.0
Income Tax Penalties and Interest Accrued [Abstract]
Accrued interest or penalties	0.0	$ 0.0
Federal [Member]
Operating Loss Carryforwards [Abstract]
NOL carryforwards	$ 62.4		$ 127.1
NOL carryforwards, expiration date	Dec. 31, 2025
Net operating loss not subject to expiration	$ 28.3
Net operating loss, subject to expiration	$ 34.1		$ 93.0
Cumulative limitation period	20 years
Federal [Member] \| Research and Development [Member]
Tax Credit Carryforward [Abstract]
Tax credit carryforwards, subject to expiration	$ 4.9
State [Member]
Operating Loss Carryforwards [Abstract]
NOL carryforwards	$ 2.2
NOL carryforwards, expiration date	Dec. 31, 2025

Commitments and Contingencies (Details) $ in Thousands	12 Months Ended
Commitments and Contingencies (Details) $ in Thousands	Dec. 31, 2019 USD ($) ft² LeaseAgreement	Dec. 31, 2018 USD ($)	Oct. 31, 2018 USD ($)	Jun. 07, 2018 USD ($)
Operating Leases [Abstract]
Restricted cash	$ 1,525	$ 1,436
Rental income received under sublease agreement	300	100
Rent expense	900	800
Lease cost [Abstract]
Operating lease cost	1,003
Total lease cost	1,003
Maturity of lease liabilities [Abstract]
2020	1,103
2021	894
2022	572
2023	73
Total lease payments	2,642
Less: interest	(242)
Total operating lease liabilities	2,400
Future annual minimum lease payment commitments [Abstract]
2020	2,742
2021	2,530
2022	2,253
2023	1,802
2024	1,783
Thereafter	20,361
Total	31,471
Leases [Abstract]
Operating lease, right-of-use assets	2,051	0
Operating lease liabilities, current	957	0
Operating lease liabilities, non-current	1,443	0
Operating lease, liability	2,400
Cash paid for amounts included in the measurement of lease liabilities [Abstract]
Operating cash flows from operating leases	$ 1,088
Weighted-average remaining lease term - operating leases	2 years 7 months 6 days
Weighted-average discount rate - operating leases	7.77%
Property Subject to Operating Lease [Member]
Operating Leases [Abstract]
Restricted cash	$ 1,000	900
NY Lease Agreement [Member]
Operating Leases [Abstract]
Term of lease agreement	1 year
Early exit from lease		100
Letter of credit	$ 200		$ 80
Letter of credit expiration date	Oct. 29, 2020
Number of days written notice	90 days
Lease expiration date	Feb. 28, 2023
Empire State Building, L.L.C [Member]
Operating Leases [Abstract]
Term of lease agreement	3 years
Term of renewal lease agreement	1 year
Letter of credit				$ 900
Letter of credit expiration date	Jun. 30, 2020
Renewal lease agreement expiration date	Jul. 31, 2021
Certificate of deposit				$ 900
NJ Lease Agreement [Member]
Operating Leases [Abstract]
Area of lease \| ft²	103,720
Term of lease agreement	15 years
Number of options to renew lease agreement \| LeaseAgreement	2
Term of renewal lease agreement	5 years
Estimated rent payments	$ 1,200
Percentage of annual increase in base rent	3.00%
Cash security deposit	$ 300
AAV Current Good Manufacturing Practice (cGMP) [Member]
Operating Leases [Abstract]
Area of lease \| ft²	50,000
ASU 2016-02 [Member]
Maturity of lease liabilities [Abstract]
Total operating lease liabilities		3,100
Leases [Abstract]
Operating lease, right-of-use assets		2,600
Operating lease, liability		3,100
Reclassification of deferred rent to right-of-use assets		$ 500
ASU 2016-02 [Member] \| NJ Lease Agreement [Member]
Maturity of lease liabilities [Abstract]
Total lease payments	$ 29,300

Agreements Related to Intellectual Property (Details) € in Thousands, $ in Thousands, $ / Vector in Millions	1 Months Ended			12 Months Ended
	Feb. 28, 2017 USD ($)	Aug. 31, 2016 USD ($)	Aug. 31, 2016 EUR (€)	Dec. 31, 2019 USD ($) Patent $ / Vector	Aug. 31, 2016 EUR (€)
Contract Research and Collaboration Agreement with Lund University and J. Richter [Member]
License Agreement [Abstract]
Research and development costs		$ 20	€ 20
Term of agreement				24 months
Agreement expiration date				Aug. 31, 2020
Contract Research and Collaboration Agreement with Lund University and J. Richter [Member] \| Maximum [Member]
License Agreement [Abstract]
Potential future obligation		$ 100			€ 100
License Agreement for Danon Disease [Member]
License Agreement [Abstract]
Research and development costs	$ 50
License Agreement for Danon Disease [Member] \| Maximum [Member]
License Agreement [Abstract]
Potential future obligation	$ 1,500
REGENXBIO, Inc. License [Member]
License Agreement [Abstract]
Research and development costs				$ 7,000
Potential future obligation				$ 13,000
Term of agreement				10 years
Termination notice period				6 months
Number of patents \| Patent				2
Options right expiry term				4 years
Fee payable (per additional vector) \| $ / Vector				2.0
Royalties payable on fees received				20.00%
Payment for License Fee				$ 1,000

Strategic Research Collaboration (Details) - USD ($) $ in Thousands		1 Months Ended	12 Months Ended
	May 16, 2018	Jan. 31, 2019	Dec. 31, 2019
Collaboration Agreement [Abstract]
Funding in strategic research collaboration	$ 3,500
Percentage of funding due upon execution of the agreement	40.00%
Funding in strategic research collaboration	$ 1,400	$ 1,400
Milestone payment made during period			$ (1,400)

CIRM Grant (Details) - USD ($) $ in Thousands	Oct. 15, 2019	Jul. 01, 2019	Apr. 30, 2019
Additional Information of CIRM Grant [Abstract]
Grant award for clinical development support			$ 6,500
Amount received from grant for eligible costs incurred	$ 400	$ 800

Related Party Transactions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Member of the Board of Directors - One [Member]
Related Party Transaction [Abstract]
Related party expenses	$ 3,600	$ 200
Member of the Board of Directors - Two [Member]
Related Party Transaction [Abstract]
Related party expenses	$ 100	$ 100

401(k) Savings Plan (Details) - USD ($) $ in Thousands	12 Months Ended
401(k) Savings Plan (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
401(k) Savings Plan [Abstract]
Percentage of matching employee contributions	4.00%
Matching employee contributions	$ 200	$ 100

Subsequent Events (Details)		12 Months Ended
Subsequent Events (Details)	Feb. 10, 2020 USD ($) Note $ / shares shares	Dec. 31, 2019 USD ($) $ / shares	Dec. 31, 2018 USD ($)
Convertible Notes Exchange Agreement [Abstract]
Aggregate principal amount remained outstanding		$ 45,049,000	$ 41,447,000
2021 Convertible Senior Notes [Member]
Convertible Notes Exchange Agreement [Abstract]
Convertible senior notes, interest rate, stated percentage		5.75%
Debt instrument, principal amount		$ 52,000,000	52,000,000
Aggregate principal amount remained outstanding		$ 45,049,000	$ 41,447,000
Debt conversion ratio		31.1876
Conversion per principal amount of debt		$ 1,000
Conversion price (in dollars per share) \| $ / shares		$ 32.08
Percentage of common stock conversion price		200.00%
Number of trading days immediately preceding notice of redemption		5 days
2021 Convertible Senior Notes [Member] \| Subsequent Event [Member]
Convertible Notes Exchange Agreement [Abstract]
Convertible senior notes, interest rate, stated percentage	5.75%
Debt instrument, aggregate principal amount exchanged	$ 39,400,000
Debt instrument, percentage of aggregate outstanding principal	76.00%
Accrued and unpaid interest amount to pay in cash	$ 119,416
Aggregate principal amount remained outstanding	$ 12,700,000
Number of common stock shares repurchased (in shares) \| shares	3,000
Aggregate amount of common stock shares repurchased	$ 71,670,000
2022 Convertible Senior Notes [Member] \| Subsequent Event [Member]
Convertible Notes Exchange Agreement [Abstract]
Convertible senior notes, interest rate, stated percentage	6.25%
Debt instrument, principal amount	$ 39,400,000
Number of notes issued \| Note	1
Debt conversion ratio	31.1876
Conversion per principal amount of debt	$ 1,000
Conversion price (in dollars per share) \| $ / shares	$ 32.06
Percentage of common stock conversion price	130.00%
Number of trading days immediately preceding notice of redemption	5 days