0001104659-21-035227 | 10-K | XBRL Viewer

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
Document and Entity Information - USD ($) $ in Millions	Dec. 31, 2020	Mar. 09, 2021	Jun. 30, 2020
Document and Entity Information
Entity Registrant Name	LEAP THERAPEUTICS, INC.
Title of 12(b) Security	Common Stock, par value $0.001
Trading Symbol	LPTX
Security Exchange Name	NASDAQ
Entity Central Index Key	0001509745
Document Type	10-K
Document Period End Date	Dec. 31, 2020
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Public Float			$ 108.6
Entity Common Stock, Shares Outstanding		59,657,742
Entity Interactive Data Current	Yes
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 52,071	$ 3,891
Research and development incentive receivable	73	185
Prepaid expenses and other current assets	130	165
Total current assets	52,274	4,241
Property and equipment, net	65	124
Right of use asset, net	528	1,026
Deferred tax assets	179	127
Deferred costs	345	831
Deposits	980	1,099
Total assets	54,371	7,448
Current liabilities:
Accounts payable	2,717	4,571
Accrued expenses	2,747	3,441
Deferred revenue - current portion	1,500
Lease liability - current portion	408	474
Total current liabilities	7,372	8,486
Non current liabilities:
Restricted stock liability	204	159
Lease liability, net of current portion	144	552
Total liabilities	7,720	9,197
Stockholders' equity (deficiency):
Common stock, $0.001 par value; 240,000,000 shares authorized; 59,657,742 and 24,194,877 shares issued and outstanding as of December 31, 2020 and 2019, respectively	60	24
Additional paid-in capital	270,155	193,319
Accumulated other comprehensive income (loss)	(579)	76
Accumulated deficit	(222,985)	(195,168)
Total stockholders' equity (deficiency)	46,651	(1,749)
Total liabilities and stockholders' equity (deficiency)	$ 54,371	$ 7,448

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2020	Dec. 31, 2019
CONSOLIDATED BALANCE SHEETS
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, authorized shares	240,000,000	240,000,000
Common stock, issued shares	59,657,742	24,194,877
Common stock, outstanding shares	59,657,742	24,194,877

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
CONSOLIDATED STATEMENTS OF OPERATIONS
License revenue	$ 1,500
Operating expenses:
Research and development	20,423	$ 24,366
General and administrative	9,616	9,085
Total operating expenses	30,039	33,451
Loss from operations	(28,539)	(33,451)
Interest income	93	313
Interest expense	(39)	(23)
Australian research and development incentives	231	132
Foreign currency gains	738	126
Loss before income taxes	(27,516)	(32,903)
Income taxes	2	3
Net loss	(27,514)	(32,900)
Dividend attributable to down round feature of warrants	(303)	(359)
Dividend attributable to Series A & B convertible preferred stock	(372)
Series A & B convertible preferred stock - beneficial conversion feature	(9,399)
Net loss attributable to common stockholders	$ (37,588)	$ (33,259)
Net loss per share
Basic (in dollars per share)	$ (0.63)	$ (1.47)
Diluted (in dollars per share)	$ (0.63)	$ (1.47)
Weighted average common shares outstanding
Basic (in shares)	59,327,713	22,582,687
Diluted (in shares)	59,327,713	22,582,687

CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS
Net loss	$ (27,514)	$ (32,900)
Other comprehensive loss:
Foreign currency translation adjustments	(655)	(226)
Comprehensive loss	$ (28,169)	$ (33,126)

- 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 STOCKHOLDERS' EQUITY (DEFICIENCY) - USD ($) $ in Thousands	Series A Convertible Preferred Stock	Series B Convertible Preferred Stock	Common Stock 2020 Public offering	Common Stock Common Stock Offering under the Lincoln Park Capital Registered Offering Purchase Agreement	Common Stock Lincoln Park Capital Commitment Purchase Agreement Offering Member	Common Stock	Additional Paid-in Capital 2020 Public offering	Additional Paid-in Capital Common Stock Offering under the Lincoln Park Capital Registered Offering Purchase Agreement	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	2020 Public offering	Common Stock Offering under the Lincoln Park Capital Registered Offering Purchase Agreement	Total
Balance at the beginning of the period at Dec. 31, 2018						$ 15			$ 162,393	$ 302	$ (153,535)			$ 9,175
Balance at the beginning of the period (in shares) at Dec. 31, 2018						14,703,159
Increase (Decrease) in Stockholders' Equity
Issuance of Series A & B Convertible Preferred Stock, net of underwriting discounts				$ 1		$ 7		$ 999	12,115				$ 1,000	12,122
Issuance of Series A & B Convertible Preferred Stock, net of underwriting discounts (in shares)				571,429	330,000	7,557,142
Issuance of common stock through ATM sales						$ 1			1,922					1,923
Issuance of common stock through ATM sales (in shares)						1,033,147
To record ATM issuance costs in Additional Paid-in Capital									(13)					(13)
To record Lincoln Park issuance costs in Additional Paid-in-Capital									(10)					(10)
Foreign currency translation adjustment										(226)				(226)
Reclassification of 2017 warrants from liability to equity									11,822		(8,374)			3,448
Dividend attributable to down round feature of warrants									359		(359)			(359)
Stock-based compensation									3,732					3,732
Net loss											(32,900)			(32,900)
Balance at the end of the period at Dec. 31, 2019						$ 24			193,319	76	(195,168)			(1,749)
Balance at the end of the period (in shares) at Dec. 31, 2019						24,194,877
Increase (Decrease) in Stockholders' Equity
Issuance of Series A & B Convertible Preferred Stock, net of underwriting discounts	$ 14,062	$ 11,260	$ 24				$ 48,252					$ 48,276
Issuance of Series A & B Convertible Preferred Stock, net of underwriting discounts (in shares)	1,421,801	1,137,442	23,625,000
Series A & B Convertible Preferred Stock discount - beneficial conversion feature	$ (5,226)	$ (4,173)							9,399					9,399
Series A & B Convertible Preferred Stock accrued	207	165							(372)					(372)
Conversion of Series A & B Convertible Preferred Stock dividends to prefunded warrants and common stock	(207)	(165)				$ 1			371					372
Conversion of Series A & B Convertible Preferred Stock dividends to prefunded warrants and common stock						156,713
Conversion of Series A convertible preferred stock to prefunded warrants	$ (8,836)								8,836					8,836
Conversion of Series A Convertible Preferred Stock to prefunded warrants (in shares)	(1,421,801)
Conversion of Series B Convertible Preferred Stock to common stock		$ (7,087)				$ 11			7,076					7,087
Conversion of Series B Convertible Preferred Stock to common stock (in shares)		(1,137,442)				11,374,420
Issuance of common stock upon exercise of warrants									348					348
Issuance of common stock upon exercise of warrants (in shares)						273,954
Issuance of common stock upon exercise of stock options									51					$ 51
Exercised (in shares)						32,778								32,778
Foreign currency translation adjustment										(655)				$ (655)
Dividend attributable to down round feature of warrants									303		(303)			(303)
Stock-based compensation									2,572					2,572
Net loss											(27,514)			(27,514)
Balance at the end of the period at Dec. 31, 2020						$ 60			$ 270,155	$ (579)	$ (222,985)			$ 46,651
Balance at the end of the period (in shares) at Dec. 31, 2020						59,657,742

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (DEFICIENCY) (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
2019 Public Offering
CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (DEFICIENCY)
Issuance of common stock, issuance costs		$ 1,102
2020 Public offering
CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (DEFICIENCY)
Issuance of common stock, issuance costs	$ 3,472

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities:
Net loss	$ (27,514)	$ (32,900)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation expense	34	47
Amortization of contract asset	135
Right-of-use asset	499	729
Stock-based compensation expense	2,572	3,732
Foreign currency (gain) loss	(738)	(126)
Change in fair value of restricted stock liability	45	159
Changes in operating assets and liabilities:
Prepaid expenses and other assets	774	302
Deferred tax assets	(36)	(3)
Research and development incentive receivable	117	643
Contract acquisition costs	(270)
Accounts payable and accrued expenses	(2,601)	1,084
Deferred revenue	1,500
Lease liability	(474)	(695)
Net cash used in operating activities	(25,957)	(26,902)
Cash flows from investing activities:
Purchases of property and equipment		(100)
Proceeds from sale of property and equipment	25	15
Net cash provided by (used in) investing activities	25	(85)
Cash flows from financing activities:
Proceeds from issuance of common stock - June 2020 Public Offering	48,518
Proceeds from issuance of common stock		12,331
Proceeds from issuance of common stock from ATM sales		1,923
Proceeds from issuance of common stock in connection with July 2019 Lincoln Park Capital Registered Offering Purchase Agreement, net of issuance costs		1,000
Proceeds from the exercise of common stock warrants	348
Proceeds from the exercise of stock options	51
Payment of deferred offering costs	(1,906)	(437)
Net cash provided by financing activities	73,997	14,817
Effect of exchange rate changes on cash and cash equivalents	115	(223)
Net decrease in cash and cash equivalents	48,180	(12,393)
Cash and cash equivalents at beginning of year	3,891	16,284
Cash and cash equivalents at end of year	52,071	3,891
Supplemental disclosure of non-cash financing activities:
Reclassification of 2017 Warrants from liability to equity		3,448
Dividend attributable to down round feature of warrants	303	359
Offering costs included in accounts payable and accrued expenses		444
Right-of-use asset recorded upon adoption of ASU 2016-02		1,755
Lease liability recorded upon adoption of ASU 2016-02		1,720
Accrued rent reclassified upon adoption of ASU 216-02		35
Reclassification of deferred offering costs to additional paid-in-capital		$ 23
Conversion of Series A convertible preferred stock to prefunded warrants	(8,836)
Series A Convertible Preferred Stock
Cash flows from financing activities:
Proceeds from issuance of convertible preferred stock	14,986
Supplemental disclosure of non-cash financing activities:
Conversion of Series A convertible preferred stock to prefunded warrants	8,836
Series A & B Convertible Preferred Stock discount - beneficial conversion feature	5,226
Series B Convertible Preferred Stock
Cash flows from financing activities:
Proceeds from issuance of convertible preferred stock	12,000
Supplemental disclosure of non-cash financing activities:
Conversion of Series B convertible preferred stock to common stock	7,087
Series A & B Convertible Preferred Stock discount - beneficial conversion feature	$ 4,173

Nature of Business, Basis of Presentation and Liquidity	12 Months Ended
Nature of Business, Basis of Presentation and Liquidity	Dec. 31, 2020
Nature of Business, Basis of Presentation and Liquidity
Nature of Business, Basis of Presentation and Liquidity	1. Nature of Business, Basis of Presentation and Liquidity Nature of Business Leap Therapeutics, Inc. was incorporated in the state of Delaware on January 3, 2011. During 2015, HealthCare Pharmaceuticals Pty Ltd. (“HCP Australia”) was formed and is a wholly owned subsidiary of the Company. On December 10, 2015, the Company entered into a merger agreement with GITR Inc. ("GITR"), an entity under common control, whereby a wholly owned subsidiary was merged with GITR and the surviving name of the wholly owned subsidiary was GITR Inc. On August 29, 2016, the Company entered into a merger agreement with Macrocure Ltd. ("Macrocure"), a publicly held, clinical-stage biotechnology company based in Petach Tikva, Israel. In connection with the merger, the Company applied to be listed on the Nasdaq Global Market. Nasdaq approved the listing, and trading in the Company’s common stock commenced on January 24, 2017, under the trading symbol "LPTX." On February 1, 2017, Macrocure's name was changed to Leap Therapeutics Ltd. In 2020, Leap Therapeutics Ltd. was dissolved. The Company is a biopharmaceutical company acquiring and developing novel therapeutics at the leading edge of cancer biology. The Company’s approach is designed to target compelling tumor-promoting and immuno-oncology pathways to generate durable clinical benefit and enhanced outcomes for patients. The Company’s programs are monoclonal antibodies that target key cellular pathways that enable cancer to grow and spread and specific mechanisms that activate the body’s immune system to identify and attack cancer. Basis of Presentation The accompanying consolidated financial statements of the Company include the accounts of its wholly owned subsidiaries and have been prepared in conformity with accounting principles generally accepted in the United States of America. All inter-company accounts and transactions are eliminated upon consolidation. Liquidity Since inception, the Company has been engaged in organizational activities, including raising capital, and research and development activities. The Company does not yet have a product that has been approved by the Food and Drug Administration (the “FDA”), has not generated any product sales revenues and has not yet achieved profitable operations, nor has it ever generated positive cash flows from operations. There is no assurance that profitable operations, if achieved, could be sustained on a continuing basis. Further, the Company’s future operations are dependent on the success of the Company’s efforts to raise additional capital, its research and commercialization efforts, regulatory approval, and, ultimately, the market acceptance of the Company’s products. In accordance with Accounting Standards Codification ("ASC") 205‑40, Going Concern, the Company has evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date that the consolidated financial statements are issued. As of December 31, 2020, the Company had cash and cash equivalents of $52,071. Additionally, the Company had an accumulated deficit of $222,985 at December 31, 2020, and during the year ended December 31, 2020, the Company incurred a net loss of $27,514. The Company expects to continue to generate operating losses for the foreseeable future. The Company believes that its cash and cash equivalents of $52,071 as of December 31, 2020, will be sufficient to fund its operating expenses for at least 12 months from the issuance of these financial statements. In addition, the Company will likely seek additional funding through public or private equity financings or government programs and will seek funding or development program cost-sharing through collaboration agreements or licenses with larger pharmaceutical or biotechnology companies. If the Company does not obtain additional funding or development program cost-sharing, or exceeds its current spending forecasts or fails to receive the research and development tax incentive payment, the Company has the ability and would be forced to: delay, reduce or eliminate certain clinical trials or research and development programs, reduce or eliminate discretionary operating expenses, and delay company and pipeline expansion, any of which could adversely affect its business prospects. The inability to obtain funding, as and when needed, could have a negative impact on the Company’s financial condition and ability to pursue its business strategies.

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2020

Summary of Significant Accounting Policies

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Principles of Consolidation

The accompanying consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany accounts and transactions are eliminated upon consolidation.

Use of Estimates

The presentation of consolidated financial statements in conformity with accounting principles generally accepted in the United States of America (“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 consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.

Cash and Cash Equivalents

The Company considers all highly liquid investments with maturities of three months or less when purchased to be cash equivalents.

Research and Development Expense

Research and development costs are expensed as incurred. Research and development expenses include personnel costs associated with research and development activities, including noncash share-based compensation and costs for third-party contractors to perform research, conduct clinical trials and manufacture drug supplies and materials. The Company accrues for costs incurred by external service providers, including contract research organizations and clinical investigators, based on its estimates of service performed and costs incurred. These estimates include the level of services performed by the third parties, patient enrollment in clinical trials, administrative costs incurred by the third parties, and other indicators of the services completed. Based on the timing of amounts invoiced by service providers, the Company may also record payments made to those providers as prepaid expenses that will be recognized as expense in future periods as the related services are rendered.

Research and development incentive income and receivable

The Company recognizes other income from Australian research and development incentives when there is reasonable assurance that the income will be received, the relevant expenditure has been incurred, and the consideration can be reliably measured. The research and development incentive is one of the key elements of the Australian Government’s support for Australia’s innovation system and is supported by legislative law primarily in the form of the Australian Income Tax Assessment Act 1997 as long as eligibility criteria are met.

Management has assessed the Company’s research and development activities and expenditures to determine which activities and expenditures are likely to be eligible under the research and development incentive regime described above. At each period end management estimates the refundable tax offset available to the Company based on available information at the time. This estimate is also reviewed by external tax advisors on an annual basis.

Under the program, a percentage of eligible research and development expenses incurred by the Company through its subsidiary in Australia are reimbursed. This percentage was 43.5% for the years ended December 31, 2020 and 2019.

The research and development incentive receivable represents an amount due in connection with the above program. The Company has recorded a research and development incentive receivable of $73 and $185 as of December 31, 2020 and 2019, respectively, in the consolidated balance sheets and other income from Australian research and development incentives of $231 and $132, in the consolidated statements of operations for the years ended December 31, 2020 and 2019, respectively, related to refundable research and development incentive program payments in Australia.

The following table shows the change in the research and development incentive receivable from January 1, 2019 to December 31, 2020:


Balance at January 1, 2019	$	836
Australian research and development incentive income, net		132
Cash received for 2018 eligible expenses		(757)
Foreign currency translation		(26)
Balance at December 31, 2019		185
Australian research and development incentive income, net		231
Cash received for 2019 eligible expenses		(331)
Foreign currency translation		(12)
Balance at December 31, 2020	$	73

Concentration of Credit Risk

Financial instruments which potentially subject the Company to credit risk consist principally of cash and cash equivalents. All cash and cash equivalents are held in United States financial institutions and money market funds. At times, the Company may maintain cash balances in excess of the federally insured amount.

Income Taxes

The Company accounts for income taxes using the asset and liability method. Under the asset and liability method, deferred income taxes are recognized for differences between the financial reporting and tax bases of assets and liabilities at enacted statutory tax rates in effect for the years in which the differences are expected to reverse. The effect on deferred taxes of a change in tax rates is recognized in income in the period that includes the enactment date. Valuation allowances are established when necessary to reduce deferred tax assets to the amount expected to be realized.

The Company follows accounting guidance concerning provisions for uncertainty in income tax positions. This guidance clarifies the accounting for income taxes by prescribing a minimum probability threshold that an uncertain tax position must meet before a financial statement benefit is recognized. The minimum threshold is defined as a tax position that is more likely than not to be sustained upon examination by the applicable taxing authority, of any related appeals or litigation processes, based on the technical merits of the position. The tax benefit to be recognized is measured as the largest amount of benefit that is greater than 50% likely of being realized upon ultimate settlement.

The Company recognizes accrued interest and penalties associated with uncertain tax position as part of the income tax provision. There were no uncertain tax positions or income tax related interest and penalties recorded for the years ended December 31, 2020 and 2019. The income tax returns of the Company for the year ended December 31, 2017 and subsequent years are subject to examination by the Internal Revenue Service and other taxing authorities, generally for three years after the work filed.

Foreign Currency Translation

The financial statements of the Company’s foreign subsidiary are measured using the local currency as the functional currency. Assets and liabilities of this subsidiary are translated into U.S. dollars at exchange rates as of the consolidated balance sheet date. Equity is translated at historical exchange rates. Revenues and expenses are translated into U.S. dollars at average rates of exchange in effect during the year. The resulting cumulative translation adjustments have been recorded as a separate component of stockholders’ deficiency. Foreign currency transaction gains and losses are included in the results of operations.

Property and Equipment

Property and equipment are stated at cost less accumulated depreciation. Depreciation expense is recognized using the straight-line method over the estimated useful life of each asset. Computer equipment is depreciated over three years. Laboratory equipment, office equipment and furniture and fixtures are depreciated over five years. Leasehold improvements are amortized over the shorter of the lease term or the estimated useful life of the asset. Upon retirement or sale, the cost of assets disposed of and the related accumulated depreciation are removed from the accounts and any resulting gain or loss is included in loss from operations. Expenditures for repairs and maintenance are charged to expense as incurred.

Impairment of Long-Lived Assets

Long-lived assets consist of property and equipment. Long-lived assets to be held and used are tested for recoverability whenever events or changes in business circumstances indicate that the carrying amount of the assets may not be fully recoverable. Factors that the Company considers in deciding when to perform an impairment review include significant underperformance of the business in relation to expectations, significant negative industry or economic trends and significant changes or planned changes in the use of the assets. If an impairment review is performed to evaluate a long-lived asset group for recoverability, the Company compares forecasts of undiscounted cash flows expected to result from the use and eventual disposition of the long-lived asset group to its carrying value. An impairment loss would be recognized when estimated undiscounted future cash flows expected to result from the use of an asset group are less than its carrying amount. The impairment loss would be based on the excess of the carrying value of the impaired asset group over its fair value. The Company did not record any impairment losses on long-lived assets during 2020 and 2019.

Deferred Costs

The Company capitalizes certain legal, professional, accounting and other third-party fees that are directly associated with in-process equity financings as deferred costs until such financings are consummated. After consummation of the equity financing, these costs are recorded in stockholders’ equity (deficiency) as a reduction of additional paid-in capital generated as a result of the offering.

The Company also capitalizes certain contract acquisition costs. During the year ended December 31, 2020, the Company incurred contract acquisition costs which were capitalized under ASC 340-40 as incremental costs of obtaining the contract with BeiGene. This cost is amortized on a straight-line basis over the performance period of the research and development services.

As of December 31, 2020 and December 31, 2019 there was $345 and $831, respectively, of deferred costs.

Deposits

Deposits as of December 31, 2020 and 2019 included $980 and $1,099, respectively, of deposits made by the Company with certain service providers that are to be applied to future payments due under the service agreements or returned to the Company if not utilized.

Warrants

On January 1, 2019, the Company adopted ASU No. 2017-11, Earnings Per Share (Topic 260), Distinguishing Liabilities from Equity (Topic 480), and Derivatives and Hedging (Topic 815) ("ASU 2017-11"), which changes the classification analysis of certain equity-linked financial instruments (or embedded features) with down round features. The amendments require entities that present earnings per share ("EPS") in accordance with Topic 260 to recognize the effect of the down round feature when triggered with the effect treated as a dividend and as a reduction of income available to common stockholders in basic EPS.

The Company concluded that the common stock warrants (the "2017 Warrants") issued in connection with the private placement of common stock completed in November 2017 (the "November 2017 Private Placement"), qualify for equity classification under ASU 2017-11. The adoption guidance of ASU 2017-11 provides for a modified retrospective adoption. The Company applied the guidance retrospectively to the 2017 Warrants by means of a cumulative-effect adjustment to its statement of financial position as of the beginning of the interim and annual period beginning January 1, 2019. The Company performed a final remeasurement of the warrant liability as of January 1, 2019 and reclassified $3,448 from warrant liability to equity.

The Company will recognize on a prospective basis the value of the effect of the down round feature in the 2017 Warrants when it is triggered (i.e., when the exercise price is adjusted downward). This value is measured as the difference between (1) the financial instrument's fair value (without the down round feature) using the pre-trigger exercise price and (2) the financial instrument's fair value (with the down round feature) using the reduced exercise price. The value of the effect of the down round feature will be treated as a dividend and a reduction to income available to common stockholders in the basic EPS calculation. In connection with the public offering, completed in February 2019 (the "2019 Public Offering"), when the 2017 Warrants were repriced from $6.085 to $1.75 as a result of a down round, the Company recorded a dividend of $359 during the year ended December 31, 2019. In connection with the private placement of common stock completed in January 2020 (the "January 2020 Private Placement"), when the 2017 Warrants were repriced from $1.75 to $1.055 as a result of a down round, the Company recorded a dividend of $303 during the year ended December 31, 2020.

Fair Value of Financial Instruments

Certain assets and liabilities are carried at fair value under GAAP. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable:

Level 1—Quoted prices in active markets for identical assets or liabilities.

Level 2—Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data.

Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques.

During the years presented, the Company has not changed the manner in which it values assets and liabilities that are measured at fair value using Level 3 inputs. The Company recognizes transfers between levels of the fair value hierarchy as of the end of the reporting period. There were no transfers within the hierarchy during the years ended December 31, 2020 and 2019.

A summary of the assets and liabilities carried at fair value in accordance with the hierarchy defined above is as follows (in thousands):


	Total		Level 1		Level 2		Level 3
December 31, 2020
Assets:
Cash equivalents	$	51,116	$	51,116	$	—	$	—
Total assets	$	51,116	$	51,116	$	—	$	—

Liabilities:
Restricted stock liability	$	204	$	—	$	204	$	—
Total liabilities	$	204	$	—	$	204	$	—

December 31, 2019
Assets:
Cash equivalents	$	3,891	$	3,891	$	—	$	—
Total assets	$	3,891	$	3,891	$	—	$	—

Liabilities:
Restricted stock liability	$	159	$	—	$	159	$	—
Total liabilities	$	159	$	—	$	159	$	—

Cash equivalents of $51,116 and $3,891 as of December 31, 2020 and 2019, respectively, consisted of overnight investments and money market funds and are classified within Level 1 of the fair value hierarchy because they are valued using quoted market prices in active markets.

The carrying value of the research and development incentive receivable, accounts payable and accrued expenses approximate their fair value due to the short-term nature of these assets and liabilities.

Leases

In February 2016, the Financial Accounting Standards Board, or FASB, issued ASU 2016-02, Leases, or ASU 2016-02, to enhance the transparency and comparability of financial reporting related to leasing arrangements. The Company adopted ASU 2016-02 on January 1, 2019, or the effective date, and used the effective date as its date of initial application.

At the inception of an arrangement, the Company determines whether the arrangement is or contains a lease based on the unique facts and circumstances present. Most leases with a term greater than one year are recognized on the balance sheet as right-of-use assets, lease liabilities and, if applicable, long-term lease liabilities. The Company has elected not to recognize on the balance sheet leases with terms of one year or less. Operating lease liabilities and their corresponding right-of-use assets are recorded based on the present value of lease payments over the expected remaining lease term. The Company has determined that the rate implicit in the lease is not determinable and the Company does not have borrowings with similar terms and collateral. Therefore, the Company considered a variety of factors, including observable debt yields from comparable companies and the volatility in the debt market for securities with similar terms, in determining that 8% was reasonable to use as the incremental borrowing rate for purposes of the calculation of lease liabilities.

In accordance with the guidance in ASU 2016-02, components of a lease should be split into three categories: lease components (e.g. land, building, etc.), non-lease components (e.g. common area maintenance, maintenance, consumables, etc.), and non-components (e.g. property taxes, insurance, etc.). Then the fixed and in-substance fixed contract consideration (including any related to non-components) must be allocated based on fair values to the lease components and non-lease components.

Although separation of lease and non-lease components is required, certain practical expedients are available. Entities may elect the practical expedient to not separate lease and non-lease components. Rather, they would account for each lease component and the related non-lease component together as a single component. The Company has elected to account for the lease and non-lease components of each of its operating leases as a single lease component and allocate all of the contract consideration to the lease component only. The lease component results in an operating right-of-use asset being recorded on the consolidated balance sheets and amortized such that lease expense is recorded on a straight line basis over the term of the lease.

Segment Information

The Company manages its operations as a single segment for the purposes of assessing performance and making operating decisions. The Company’s singular focus is developing novel, targeted drugs for the treatment of cancer. Substantially all of the Company’s tangible assets are held in the United States.

Patent Costs

All patent related costs incurred in connection with filing and prosecuting patent applications are expensed as incurred due to the uncertainty about the recovery of the expenditure. Amounts incurred are classified as general and administrative expenses.

Stock-Based Compensation

The Company measures all stock options and other stock-based awards granted to employees based on the fair value on the date of the grant and recognizes compensation expense of those awards, net of estimated forfeitures, over the requisite service period, which is generally the vesting period of the respective award. Generally, the Company issues stock options to employees with only service-based vesting conditions and records the expense for these awards using the straight-line method.

The Company measures stock-based awards granted to consultants and nonemployees based on the fair value of the award on the date on which the related service is complete. Compensation expense is recognized over the period during which services are rendered by such consultants and nonemployees until completed. At the end of each financial reporting period prior to completion of the service, the fair value of these awards is remeasured using the then current fair value of the Company’s common stock and updated assumption inputs in the Black-Scholes option-pricing model.

Stock-based compensation is classified in the accompanying consolidated statements of operations based on the function to which the related services are provided.

The fair value of each stock option grant is estimated on the date of grant using the Black-Scholes option-pricing model. The Company historically has been a private company and lacks company-specific historical and implied volatility information. Therefore, it estimates its expected stock volatility based on the historical volatility of a publicly traded set of peer companies and expects to continue to do so until such time as it has adequate historical data regarding the volatility of its own traded stock price. The expected term of the Company’s stock options granted to employees has been determined utilizing the “simplified” method for awards that qualify as “plain-vanilla” options. The expected term of stock options granted to nonemployees is equal to the contractual term of the option award. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. Expected dividend yield of zero is based on the fact that the Company has never paid cash dividends on common stock and does not expect to pay any cash dividends in the foreseeable future.

Revenue Recognition

The Company records revenue in accordance with Accounting Standards Codification, or ASC, Topic 606, Revenue From Contracts with Customers. This standard applies to all contracts with customers, except for contracts that are within the scope of other standards, such as leases, insurance, collaboration arrangements and financial instruments. Under Topic 606, an entity recognizes revenue when its customer obtains control of promised goods or services, in an amount that reflects the consideration that the entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements that an entity determines are within the scope of Topic 606, the entity performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. The Company only applies the five step model to contracts when it is probable that the entity will collect the consideration it is entitled to in exchange for the goods or services it transfers to the customer. At contract inception, once the contract is determined to be within the scope of Topic 606, the Company assesses the goods or services promised within each contract and determines those that are performance obligations, and assesses whether each promised good or service is distinct. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied.

License revenue. The Company's performance obligations under its license agreements may include providing intellectual property licenses, performing technology transfer, performing research and development consulting services and notifying the customer of any enhancements to licensed technology or new technology that it discovers, among others. The Company determined that its performance obligations under its license agreements as evaluated at contract inception were not distinct and represented a single performance obligation. Upfront payments are amortized to revenue on a straight line basis over the performance period. Upfront payment contract liabilities resulting from the Company's license agreements do not represent a financing component as the payment is not financing the transfer of goods or services, and the technology underlying the licenses granted reflects research and development expenses already incurred by the Company. Generally, all amounts received or due other than sales-based milestones and royalties are classified as license revenues. Sales-based milestones and royalties under the Company's license agreements will be recognized as royalty revenue in the period the related sale occurred. The Company generally invoices its licensees upon the completion of the effort or achievement of a milestone, based on the terms of each agreement. Deferred revenue arises from amounts received in advance of the culmination of the earnings process and is recognized as revenue in future periods as performance obligations are satisfied. Deferred revenue expected to be recognized within the next twelve months is classified as a current liability.

Research and Development Services. The promises under the Company's license agreements may include research and development services to be performed by the Company on behalf of the customer. Payments or reimbursements resulting from the Company's research and development efforts are recognized as the services are performed and presented on a gross basis because the Company is the principal for such efforts.

Customer Options. If an arrangement is determined to contain customer options that allow the customer to acquire additional goods or services, the goods and services underlying the customer options that are not determined to be material rights are not considered to be performance obligations at the outset of the arrangement, as they are contingent upon option exercise. The Company evaluates the customer options for material rights, or options to acquire additional goods or services for free or at a discount. If the customer options are determined to represent a material right, the material right is recognized as a separate performance obligation at the outset of the arrangement. The Company allocates the transaction price to material rights based on the relative standalone selling price, which is determined based on the identified discount and the probability that the customer will exercise the option. Amounts allocated to a material right are not recognized as revenue until (1) the option is exercised and the additional goods or services are transferred or (2) the option expires.

Milestone Payments. At the inception of each arrangement that includes research or development milestone payments, the Company evaluates whether the milestones are considered probable of being achieved and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the control of the Company or the licensee, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. The Company evaluates factors such as the scientific, clinical, regulatory, commercial, and other risks that must be overcome to achieve the particular milestone in making this assessment. There is considerable judgment involved in determining whether it is probable that a significant revenue reversal would not occur. At the end of each subsequent reporting period, the Company reevaluates the probability of achievement of all milestones subject to constraint and, if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect revenues and earnings in the period of adjustment.

Royalties. For arrangements that include sales-based royalties, including milestone payments upon first commercial sales and milestone payments based on a level of sales, which are the result of a customer-vendor relationship and for which the license is deemed to be the predominant item to which the royalties relate, the Company recognizes revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied or partially satisfied. To date, the Company has not recognized any royalty revenue resulting from any of its licensing arrangements.

Collaborative Arrangements

The Company analyzes its collaboration arrangements to assess whether such arrangements involve joint operating activities performed by parties that are both active participants in the activities and exposed to significant risks and rewards dependent on the commercial success of such activities and therefore within the scope of ASC Topic 808, Collaborative Arrangements (ASC 808). This assessment is performed throughout the life of the arrangement based on changes in the responsibilities of all parties in the arrangement. For collaboration arrangements within the scope of ASC 808 that contain multiple elements, the Company first determines which elements of the collaboration are deemed to be within the scope of ASC 808 and which elements of the collaboration are more reflective of a vendor-customer relationship and therefore within the scope of ASC 606. For elements of collaboration arrangements that are accounted for pursuant to ASC 808, an appropriate recognition method is determined and applied consistently, generally by analogy to ASC 606. Amounts that are owed to collaboration partners are recognized as an offset to collaboration revenues as such amounts are incurred by the collaboration partner. Where amounts owed to a collaboration partner exceed the Company's collaboration revenues in each quarterly period, such amounts are classified as research and development expense. Reimbursements from and payments to the customer that are the result of a collaborative relationship with a partner, instead of a customer relationship, such as co-development activities, are recorded as a reduction to research and development expense. For those elements of the arrangement that are accounted for pursuant to ASC 606, the Company applies the five-step model described above under ASC 606.

See Note 3 for a complete discussion of the revenue recognition for the Company's license agreement.

Net Loss per Share

Basic net loss per share is computed using the weighted average number of common shares outstanding during the period. Diluted net loss per share is computed using the weighted average number of common shares outstanding during the period and, if dilutive, the weighted average number of potential shares of common stock, including the assumed exercise of stock options and warrants.

Subsequent Events

The Company considers events or transactions that occur after the balance sheet date but prior to the issuance of the financial statements to provide additional evidence for certain estimates or to identify matters that require additional disclosure. Subsequent events have been evaluated as required.

Recent Accounting Pronouncements

From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board, or FASB, and are early adopted by the Company or adopted as of the specified effective date.

In July 2017, the FASB issued ASU No. 2017-11, Earnings Per Share (Topic 260), Distinguishing Liabilities from Equity (Topic 480), and Derivatives and Hedging (Topic 815) ("ASU 2017-11"), which changes the classification analysis of certain equity-linked financial instruments (or embedded features) with down round features. The amendments require entities that present earnings per share ("EPS") in accordance with Topic 260 to recognize the effect of the down round feature when triggered with the effect treated as a dividend and as a reduction of income available to common shareholders in basic EPS. The new standard is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. The Company adopted this standard effective January 1, 2019 and concluded that the 2017 Warrants qualified for equity classification. The Company applied the guidance retrospectively to the 2017 Warrants by means of a cumulative-effect adjustment to its statement of financial position as of the beginning of the interim and annual period beginning January 1, 2019. The Company performed a final remeasurement of the warrant liability as of January 1, 2019 and reclassified $3,448 to stockholders’ equity.

In February 2016, the FASB issued ASU 2016-02, Leases, or ASU 2016-02. ASU 2016-02 requires a lessee to recognize on its balance sheet (for both finance and operating leases) a liability to make lease payments and a right-of-use asset representing its right to use the underlying asset for the lease term. ASU 2016-02 is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. The Company adopted ASU 2016-02 on January 1, 2019, the effective date, and used the effective date as its date of initial application. As such, the Company did not adjust prior period amounts. The Company also elected to adopt the practical expedients upon transition, which permit companies to not reassess lease identification, classification, and initial direct costs under ASU 2016-02 for leases that commenced prior to the effective date (see Note 6).

BeiGene Exclusive Option and License Agreement

12 Months Ended

Dec. 31, 2020

BeiGene Exclusive Option and License Agreement

BeiGene Exclusive Option and License Agreement

3. BeiGene Exclusive Option and License Agreement

Terms of Agreement

On January 3, 2020, the Company entered into an exclusive option and license agreement (the "BeiGene Agreement") with BeiGene, Ltd. ("BeiGene") for the clinical development and commercialization of DKN-01, in Asia (excluding Japan), Australia, and New Zealand. The Company retains exclusive rights for the development, manufacturing, and commercialization of DKN-01 for the rest of the world.

Pursuant to the BeiGene Agreement, the Company received an upfront cash payment of $3,000 from BeiGene in exchange for granting BeiGene an option to an exclusive license to develop and commercialize DKN-01 in Asia (excluding Japan), Australia, and New Zealand. The Company is eligible to receive up to $132,000 in future option exercise and milestone payments, based upon the achievement of certain development, regulatory, and sales milestones, as well as tiered royalties on any product sales of DKN-01 in the licensed territory.

The Company is responsible for conducting development activities prior to the exercise of the option. After the option is exercised, BeiGene is solely responsible for the development and commercialization of DKN-01 in the licensed territory. The BeiGene Agreement continues in effect until the earlier of: (i) 120 days after the end of the option period, if BeiGene has not exercised the option by such date; and (ii) on a country-by country and Licensed Product-by-Licensed Product (as defined in the BeiGene Agreement) basis, the expiration of the Royalty Term (as defined in the BeiGene Agreement) applicable to such licensed product in such country. At any time, BeiGene may terminate the BeiGene Agreement by providing at least 60 days written notice of termination to the Company. Upon termination of the License Agreement, all rights granted by the Company to BeiGene terminate.

Revenue Recognition

The Company evaluated the BeiGene Agreement to determine whether it is a collaborative arrangement for purposes of ASC 808. The Company concluded that because both parties were active participants and were exposed to the risks and rewards of the BeiGene Agreement, that such activities are under the scope of ASC 808. The Company concluded that BeiGene was a customer with regard to the combined license and research and development activities and as such the contract should be evaluated under ASC 606.

In determining the appropriate amount of revenue to be recognized under ASC 606 as the Company fulfills its obligations under the Agreement, the Company performs the following steps: (i) identifies the promised goods or services in the contract; (ii) determines whether the promised goods or services are performance obligations including whether they are distinct in the context of the contract; (iii) measures the transaction price, including any constraints on variable consideration; (iv) allocates the transaction price to the performance obligations; and (v) recognizes revenue when (or as) the Company satisfies each performance obligation.

The Company identified the following material promises under the BeiGene Agreement: (1) option to an exclusive license to develop and commercialize DKN-01 in Asia (excluding Japan), Australia, and New Zealand, (2) participation in a joint development committee, (3) technology transfer services and (4) pre-option research and development services. The Company determined that the option to an exclusive license in the territory does not represent a material right. Additionally, the Company determined that the participation in the joint development committee, research and development services and technology transfer services are not distinct from each other, as each has limited value without the other. As such, for the purposes of ASC 606, the Company determined that these four material promises, described above, should be combined into a single performance obligation.

The Company determined the transaction price is equal to the up-front fee of $3,000. The transaction price was fully allocated to the single performance obligation and is recognized as revenue on a straight-line basis over the performance period of the research and development services. During the year ended December 31, 2020, the Company recognized $1,500 of license revenue related to the up-front fee received from BeiGene. The Company did not have any such license revenue during the year ended December 31, 2019.

Cost of Contract Acquisition

The Company incurred contract acquisition costs of $270 which were capitalized under ASC 340-40 as incremental costs of obtaining the contract with BeiGene. This cost is amortized on a straight-line basis over the performance period of the research and development services. The total amount of amortization expense during the year ended December 31, 2020 was $135 and the closing balance recorded in deferred costs as of December 31, 2020 was $135.

Royalties

As the license is deemed to be the predominant item to which sales-based royalties relate, the Company will recognize revenue when the related sales occur. No royalty revenue was recognized during the year ended December 31, 2020.

The following table presents a summary of the activity in the Company's contract liabilities, related to the upfront cash payment received of $3,000, during the year ended December 31, 2020 (in thousands):


	Balance at						Balance at
	January 1, 2020		Additions		Revenue recognized		December 31, 2020
Total contract liabilities	$	—	$	3,000	$	(1,500)	$	1,500

Property and Equipment, Net

12 Months Ended

Dec. 31, 2020

Property and Equipment, Net

Property and Equipment, Net

4. Property and Equipment, Net

Property and equipment, net consisted of the following:


	December 31,
	2020		2019
Computer office equipment	$	51	$	51
Leasehold improvements		69		69
Lab equipment		76		113
Furnitures and fixtures		30		30
		226		263
Less: accumulated depreciation		(161)		(139)
Property and equipment, net	$	65	$	124

Depreciation expense was $34 and $47 for the years ended December 31, 2020 and 2019, respectively.

Accrued Expenses

12 Months Ended

Dec. 31, 2020

Accrued Expenses

Accrued Expenses

5. Accrued Expenses

Accrued expenses consist of the following:


	December 31,
	2019		2018
Clinical trials	$	795	$	1,828
Professional fees		255		609
Payroll and related expenses		1,697		1,004
Accrued expenses	$	2,747	$	3,441

Leases

12 Months Ended

Dec. 31, 2020

Leases

Leases

6. Leases

In February 2016, the FASB issued ASU 2016-02, Leases , or ASU 2016-02. ASU 2016-02 requires a lessee to recognize on its balance sheet (for both finance and operating leases) a liability to make lease payments and a right-of-use asset representing its right to use the underlying asset for the lease term. The Company adopted ASU 2016-02 on January 1, 2019, on the effective date, and used the effective date as its date of initial application. As such, the Company did not adjust prior period amounts. The Company also elected to adopt the practical expedients upon transition, which permit companies to not reassess lease identification, classification, and initial direct costs under ASU 2016-02 for leases that commenced prior to the effective date.

The Company has operating leases for real estate in the United States and does not have any finance leases. The Company’s leases may contain options to renew and extend lease terms and options to terminate leases early. Reflected in the right-of-use asset and lease liability on the Company’s consolidated balance sheets are the periods provided by renewal and extension options that the Company is reasonably certain to exercise, as well as the periods provided by termination options that the Company is reasonably certain to not exercise.

The Company has existing leases that include variable lease and non-lease components that are not included in the right-of-use asset and lease liability and are reflected as an expense in the period incurred. Such payments primarily include common area maintenance charges and increases in rent payments that are driven by factors such as future changes in an index (e.g., the Consumer Price Index).

In calculating the present value of future lease payments, the Company utilized its incremental borrowing rate based on the remaining lease term at the date of adoption. The Company has elected to account for each lease component and its associated non-lease components as a single lease component and has allocated all of the contract consideration across lease components only. This will potentially result in the initial and subsequent measurement of the balances of the right-of-use asset and lease liability for leases being greater than if the policy election was not applied. The Company has existing net leases in which the non-lease components (e.g. common area maintenance, maintenance, consumables, etc.) are paid separately from rent based on actual costs incurred and therefore are not included in the right-of-use asset and lease liability and are reflected as an expense in the period incurred. On January 1, 2019, the Company recorded a right-of-use asset of $1,720 and a lease liability of $1,720 on its consolidated balance sheets and reclassified prepaid rent to the right-of-use asset of $35. As of December 31, 2020, a right-of-use asset of $528 and lease liability of $552 are reflected on the consolidated balance sheet. The Company recorded rent expense of $549 and $837, respectively, during the years ended December 31, 2020 and 2019.

Future lease payments under non-cancelable operating leases as of December 31, 2020 are detailed as follows:


Future Operating Lease Payments
2021		434
2022		146
Total Lease Payments		580
Less: imputed interest		(28)
Total operating lease liabilities	$	552

Warrants

12 Months Ended

Dec. 31, 2020

Warrants

Warrants

7. Warrants

As of December 31, 2020, outstanding warrants to purchase common stock, all of which are classified as equity warrants, consisted of the following:


December 31, 2020
	Number of Shares
Date Exercisable	Issuable	Exercise Price
1/23/2017	54,516	$	0.01
11/14/2017	2,549,840	$	1.055
2/5/2019	7,491,442	$	1.95
3/5/2020	14,413,902	$	0.001
3/5/2020	25,945,035	$	2.11
6/22/2020	2,250,000	$	0.001
	52,704,735

2017 Warrants

The 2017 Warrants contain full ratchet anti-dilution protection provisions. Prior to January 1, 2019, the Company classified the 2017 Warrants as a liability on its consolidated balance sheet because each warrant represented a freestanding financial instrument that, due to the potential variable nature of the exercise price, is not considered to be indexed to the Company’s own shares. The warrant liability was initially recorded at fair value upon entering into the November 2017 Private Placement and has been subsequently remeasured to fair value at each reporting date. Changes in the fair value of the warrant liability were recognized as gains (losses) in the Company’s consolidated statement of operations.

On January 1, 2019, the Company adopted ASU 2017-11 and concluded that the 2017 Warrants now qualify for equity classification. The Company applied the guidance retrospectively to the 2017 Warrants by means of a cumulative-effect adjustment to its statement of financial position as of the beginning of the interim and annual period beginning January 1, 2019. The Company performed a final remeasurement of the warrant liability as of January 1, 2019 and reclassified $3,448 to additional paid in capital.

The Company will recognize on a prospective basis the value of the effect of the down round feature in the warrant when it is triggered (i.e., when the exercise price is adjusted downward). This value is measured as the difference between (1) the financial instrument’s fair value (without the down round feature) using the pre-trigger exercise price and (2) the financial instrument’s fair value (with the down round feature) using the reduced exercise price. The value of the effect of the down round feature will be treated as a dividend and a reduction to income available to common shareholders in the basic EPS calculation. In connection with the 2019 Public Offering, when the 2017 Warrants were repriced from $6.085 to $1.75, the Company recorded a dividend of $359 during the year ended December 31, 2019. In connection with the January 2020 Private Placement, when the 2017 Warrants were repriced from $1.75 to $1.055, the Company recorded a dividend of $303 during the year ended December 31, 2020.

During the year ended December 31, 2020, 208,254 of the 2017 Warrants were exercised for cash resulting in gross proceeds to the Company of $220.

2019 Warrants

On February 5, 2019, in connection with the 2019 Public Offering, the Company issued immediately exercisable warrants (the “2019 Warrants”) to purchase 7,557,142 shares of common stock to investors. The 2019 Warrants have an exercise price of $1.95 per share and expire on February 5, 2026. The 2019 Warrants qualify for equity classification.

During the year ended December 31, 2020, 65,700 of the 2019 Warrants were exercised for cash resulting in gross proceeds to the Company of $128.

March 2020 Warrants

On January 3, 2020, the Company entered into a Securities Purchase Agreement with investors, providing for a private placement transaction exempt from the Securities Act of 1933, as amended, pursuant to which the Company issued and sold 1,421,801 shares of its Series A Preferred Stock, at a purchase price of $10.54 per share, 1,137,442 shares of its Series B Preferred Stock at a purchase price of $10.55 per share, and one (1) share of the Company's Special Voting Stock entitling the purchaser of Series A Preferred Stock to elect one member of the Company's board of directors.

On March 5, 2020, the Company's stockholders approved the conversion of the Series A Preferred Stock into a pre-funded warrant to purchase 14,413,902 shares of common stock at an exercise price of $0.001 (the “March 2020 Pre-funded Warrants”) and the conversion of the Series B Preferred Stock into 11,531,133 shares of common stock. Each investor also received a warrant to purchase an equal number of shares of common stock at an exercise price of $2.11 per share (the “Coverage Warrants”). The March 2020 Pre-funded Warrants and the Coverage Warrants expire on March 5, 2027 and qualify for equity classification.

June 2020 Warrants

On June 22, 2020, the Company completed a Public Offering (“the 2020 Public Offering”) whereby the Company issued 20,250,000 shares of its common stock, at $2.00 per share and, in lieu of common stock, offered pre-funded warrants (the “June 2020 Pre-funded Warrants”) to purchase up to 2,250,000 shares of its common stock to certain investors. The June 2020 Pre-funded Warrants have an exercise price of $0.001 per share, expire on June 22, 2027 and qualify for equity classification.

Common Stock	12 Months Ended
Common Stock	Dec. 31, 2020
Common Stock
Common Stock	8. Common Stock Each share of common stock entitles the holder to one vote on all matters submitted to a vote of the Company’s stockholders. Common stockholders are entitled to receive dividends, as may be declared by the board of directors, if any, subject to the preferential dividend rights of the preferred stockholders. Through December 31, 2020, no dividends have been declared for shares of common stock. Public Offering of Common Stock—February 2019 On February 5, 2019, the Company completed the 2019 Public Offering whereby the Company issued 7,557,142 shares of its common stock at a price of $1.75 per share, which included 985,714 shares issued pursuant to the underwriters’ exercise of their option to purchase additional shares of common stock, each share issued with a warrant to purchase one share of common stock. Each warrant has an exercise price of $1.95 per share with an exercise period expiring seven years from the date of issuance. The aggregate net proceeds received by the Company from the 2019 Public Offering were approximately $12,122, net of underwriting discounts and commissions and estimated offering expenses payable by the Company. Issuance of Common Stock under Distribution Agreement—2019 On September 7, 2018, the Company filed a Prospectus Supplement to register the offer and sale of shares of common stock having an aggregate offering price of up to $30,000 pursuant to the terms of a distribution agreement, or the Distribution Agreement, with Raymond James & Associates, Inc. During the year ended December 31, 2019, the Company issued 1,033,147 shares under the Distribution Agreement, for net proceeds of $1,923. In June 2020, the Company terminated the Distribution Agreement and did not issue any shares under the Distribution Agreement during the year ended December 31, 2020. Lincoln Park Purchase Agreements On July 10, 2019, the Company entered into a Commitment Purchase Agreement and a Registration Rights Agreement with Lincoln Park, pursuant to which the Company has the right to sell to Lincoln Park up to $20,000 in shares of its common stock, $0.001 par value per share, subject to certain limitations and conditions set forth in the Commitment Purchase Agreement. As consideration for Lincoln Park’s commitment to purchase shares of common stock pursuant to the Commitment Purchase Agreement, the Company issued to Lincoln Park 330,000 shares of common stock. The Company did not receive any cash proceeds from the issuance of such shares. During the year ended December 31, 2020, the Company did not issue any shares under the Commitment Purchase Agreement. On July 11, 2019, the Company entered into a Registered Offering Purchase Agreement, under which the Company agreed to sell to Lincoln Park, and Lincoln Park agreed to purchase 571,429 shares of common stock, at a price of $1.75 per share for an aggregate purchase price of $1,000. January 2020 Private Placement On January 3, 2020, the Company issued and sold 1,421,801 shares of its Series A Preferred Stock at a purchase price of $10.54 per share, 1,137,442 shares of its Series B Preferred Stock at a purchase price of $10.55 per share, and one (1) share of its Special Voting Stock, entitling the purchaser of Series A Preferred Stock to elect one member of the Company’s board of directors, for aggregate net proceeds to the Company of approximately $25,322. On March 5, 2020, the Company’s stockholders approved the conversion of the Series A Preferred Stock into a pre-funded warrant to purchase 14,413,902 shares of common stock at an exercise price of $0.001 per share and the conversion of the Series B Preferred Stock into 11,531,133 shares of its common stock, par value $0.001 per share. Each investor also received the Coverage Warrants to purchase an equal number of shares at an exercise price of $2.11 per share. In connection with the January 2020 Private Placement, Series A Preferred Stock holders and Series B Preferred Stock holders were entitled to cash dividends at a fixed cumulative percentage of 8% per annum plus any dividends declared on outstanding common stock on an as-converted basis, effective on the issuance date of the Series A Preferred Stock and Series B Preferred Stock. The cash dividends were converted to shares of common stock upon the conversion of the Series A Preferred Stock to pre-funded warrants and Series B Preferred Stock to common stock. During the year ended December 31, 2020, the Company recorded $372 of Series A Preferred Stock and Series B Preferred Stock dividends, which qualify as cumulative dividends, and in the calculation of EPS are subtracted from net income in arriving at income attributable to common stockholders. The Company determined that the embedded conversion features of the Series A Preferred Stock and Series B Preferred Stock to receive the Coverage Warrants each met the definition of a contingent beneficial conversion feature and should be accounted for separately as a derivative. The recognition of the beneficial conversion feature occurred upon the conversion of the Series A Preferred Stock into pre-funded warrants and Series B Preferred Stock into common stock and the issuance of the Coverage Warrants. The Company measured the contingent beneficial conversion features’ intrinsic values on January 3, 2020 and determined that the beneficial conversion features were valued at $5,226 for Series A and $4,173 for Series B, respectively. Upon conversion, the discount originated by the contingent beneficial conversion feature, at its intrinsic value for Series A Preferred Stock and Series B Preferred Stock, was immediately recognized as a dividend. The dividend is reflected as an adjustment to basic and diluted net loss per share attributable to common stockholders. Public Offering of Common Stock — June 2020 On June 22, 2020, the Company completed the 2020 Public Offering, whereby the Company issued 20,250,000 shares of its common stock at $2.00 per share and, in lieu of common stock, issued certain investors 2,250,000 of its June 2020 Pre-funded Warrants. The June 2020 Pre-funded Warrants have an exercise price of $0.001 per share, expire on June 22, 2027 and qualify for equity classification. On June 25, 2020, the underwriters exercised their right to purchase 3,375,000 additional shares of the Company’s common stock at the public offering price per share of common stock, less underwriting discounts and commissions. The aggregate net proceeds received by the Company from the 2020 Public Offering were approximately $48,276, net of underwriting discounts and commissions and offering expenses payable by the Company.

Stock-Based Compensation

12 Months Ended

Dec. 31, 2020

Stock-Based Compensation

Stock-Based Compensation

9. Stock-Based Compensation

Equity Incentive Plans

In September 2012, the Company adopted the 2012 Equity Incentive Plan, as amended, which provides designated employees of the Company and its affiliates, certain consultants and advisors who perform services for the Company and its affiliates, and nonemployee members of the Board of Directors of the Company and its affiliates with the opportunity to receive grants of incentive stock options, nonqualified stock options and stock awards.

On January 20, 2017, the Company's stockholders approved the 2016 Equity Incentive Plan (the "2016 Plan"). Beginning on January 1, 2018, the number of shares of common stock authorized for issuance pursuant to the 2016 Plan was increased each January 1 by an amount equal to four percent (4%) of the Company's outstanding common stock as of the end of the immediately preceding calendar year or such other amount as determined by the compensation committee of the Company's board of directors. During the year ended December 31, 2019, the compensation committee of the board of directors authorized an additional 3,000,000 shares of common stock to be added to the shares authorized for issuance under the 2016 Plan.

As of December 31, 2020, there were 340,144 shares available for grant under the Company’s Equity Incentive Plans.

A summary of stock option activity under the Company’s Equity Incentive Plans is as follows:


		Weighted
		Average		Weighted	Aggregate
		Exercise Price		Average Remaining	Intrinsic
	Options	Per Share		Life in Years	Value
Outstanding at December 31, 2018	2,761,912	$	11.30	8.01	$	—
Granted	1,481,975	$	1.48
Forfeited	(219,321)	$	15.14
Outstanding at December 31, 2019	4,024,566	$	7.48	7.98	$	2
Granted	2,662,500	$	2.10
Exercised	(32,778)	$	1.53
Forfeited	(260,435)	$	6.95
Outstanding at December 31, 2020	6,393,853	$	5.29	7.96	$	1,961
Options exercisable at December 31, 2020	3,482,169	$	7.83	7.07	$	722
Options vested and expected to vest at December 31, 2020	6,393,853	$	5.29	7.96	$	1,961

The assumptions that the Company used to determine the grant-date fair value of stock options granted to employees and directors during the years ended December 31, 2020 and 2019 were as follows, presented on a weighted average basis:


	Year Ended December 31,
	2020		2019
Expected volatility	66.94	%	66.94	%
Weighted average risk-free interest rate	0.66	%	2.07	%
Expected dividend yield	0.00	%	0.00	%
Expected term (in years)	6.85		6.77

Stock options generally vest over a three or four year period, as determined by the compensation committee of the board of directors at the time of grant. The options expire ten years from the grant date. As of December 31, 2020, there was approximately $3,947 of unrecognized compensation cost related to non-vested stock options, which is expected to be recognized over a remaining weighted-average period of approximately 2.08 years.

The Company recognized stock-based compensation expense related to the issuance of stock option awards to employees and non-employees in the consolidated statements of operations as follows:


	Year Ended
	December 31,
	2020		2019
Research and development	$	1,028	$	714
General and administrative		1,296		3,018
Total	$	2,324	$	3,732

Restricted Stock Units

During the years ended December 31, 2020 and 2019, the Company issued 92,500 and 181,000 restricted stock units (“RSUs”), respectively, to employees under the 2016 Plan. Upon vesting of the RSUs, the Company has the option to settle the award by either issuing shares of the Company's common stock or paying an amount of cash equal to the fair value of the Company's common stock on the settlement date. During the years ended December 31, 2020 and 2019, the Company recorded stock based compensation expense related to liability classified RSUs of $204 and $265, respectively. In each of October 2019 and January 2020, the Company cash settled 90,500 RSUs. In January 2021, the Company cash settled 92,500 RSUs. As of December 31, 2020 and 2019, these RSUs are classified as restricted stock liability in the consolidated balance sheets of $204 and $159, respectively, as they contain a cash settlement option.

During the year ended December 31, 2020, the Company granted 660,606 RSUs to an executive officer that will cliff vest and will be settled after three years of continuous service, or upon a change of control of the Company, whichever is earlier, pursuant to the 2016 Plan. During the year ended December 31, 2020, the Company recognized $248 of stock based compensation expense related to equity classified RSUs, as they do not contain a cash settlement option.

The following table presents a summary of outstanding RSUs under the 2016 Plan as of December 31, 2020:


		Weighted
	Number of	Average
	Shares	Fair Value
Outstanding at December 31, 2018	—	$	—
Awarded	181,000	$	1.74
Settled in cash	(90,500)	$	1.17
Outstanding at December 31, 2019	90,500	$	1.76
Awarded	753,106	$	1.49
Settled in cash	(90,500)	$	1.76
Outstanding at December 31, 2020	753,106	$	1.52

As of December 31, 2020, there were 753,106 shares outstanding covered by RSUs that were vested and expected to vest. The weighted average grant date fair value of these shares of restricted stock was $1.49 per share and the aggregate grant date fair value of these shares of restricted stock was approximately $1,112. As of December 31, 2020, there was approximately $690 of unrecognized compensation costs related to RSUs granted to employees, which are expected to be recognized as expense over a remaining weighted average period of 2.21 years.

Income Taxes

12 Months Ended

Dec. 31, 2020

Income Taxes

Income Taxes

10. Income Taxes

During the year end December 31, 2020, the Company’s Israeli operations were dissolved and as a result, the Company wrote off all existing deferred tax assets related to the Israeli operations which consisted primarily of net operating loss carryforwards. The write off of the deferred tax assets was offset by an equal reduction in the valuation allowance.

As of December 31, 2020, the Company had federal and state net operating loss carryforwards of approximately $160,531 and $141,751, respectively, which begin to expire in 2030 for federal and state purposes. The Company’s federal net operating losses include $79,223 which can be also carried forward indefinitely.

The Company may be able to utilize its net operating loss carryforwards to reduce future federal and State income tax liabilities. However, these net operating losses are subject to various limitations under Internal Revenue Code (“IRC”) section 382, which limit the use of net operating loss carryforwards to the extent there has been an ownership change of more than 50 percentage points. In addition, the net operating loss carryforwards are subject to examination by taxing authorities and could be adjusted or disallowed due to such exams. Although the Company has not undergone an IRC section 382 analysis, it is possible that the utilization of the Company’s net operating loss carryforwards may be limited.

In addition, the Company has federal and state research and development tax credits of approximately $3,770 and $645, respectively, that begin to expire in 2030 for federal and state tax purposes.

There is no provision for income taxes in the United States or Israel, because the Company has historically incurred operating losses and maintains a full valuation allowance against its deferred tax assets in these jurisdictions. The deferred tax asset recorded in the consolidated balance sheet relates to our Australian operations.

Income (loss) before income taxes consisted of the following:


	Year Ended
	December 31,
	2020		2019
U.S.	$	(28,699)	$	(32,875)
Foreign		1,183		(28)
Loss before income taxes	$	(27,516)	$	(32,903)

A summary of the Company’s current and deferred expense for income tax is as follows:


	Year Ended
	December 31,
	2020		2019
Current expense (benefit):
Federal	$	—	$	—
State		—		—
Foreign		40		—
Total current expense (benefit):	$	40	$	—
Deferred expense (benefit):
Federal	$	—	$	—
State		—		—
Foreign		(42)		(3)
Total deferred expense (benefit):	$	(42)	$	(3)
Total income tax expense (benefit):	$	(2)	$	(3)

A reconciliation of the Company’s statutory income tax rate to the Company’s effective income tax rate is as follows:


	Year Ended
	December 31,
	2020		2019
Income at US Statutory Rate	21.00	%	21.00	%
State Taxes, net of Federal benefit	6.97	%	6.79	%
Permanent Differences	(1.09)	%	(0.33)	%
Tax Credits	5.98	%	3.30	%
Tax Law Change	(0.04)	%	0.00	%
Foreign Rate Differential	(0.46)	%	0.07	%
Israel DTA write-off	(70.15)	%	0.00	%
Valuation Allowance	36.56	%	(40.18)	%
Other	1.23	%	9.35	%
	0.00	%	0.00	%

The significant components of the Company’s deferred tax assets as of December 31, 2020 and 2019 were as follows:


	Year Ended
	December 31,
	2020		2019
Accrued expenses		455		277
License Fees		1,168		1,332
Stock Options		3,759		2,584
Other		228		115
State net operating loss carryforwards		8,959		7,431
State research tax credits		625		510
Federal net operating loss carryforwards		33,711		47,845
Federal research tax credits		4,943		3,770
Total deferred tax assets		53,848		63,864
Valuation allowance		(53,669)		(63,737)
Net deferred tax asset (liability)		179		127

As of December 31, 2020 and 2019, the Company had provided a full valuation allowance against its net deferred tax assets, except for its Australian deferred tax assets, because realization of any future tax benefit cannot be reasonably assured. The valuation allowance increased during the year ended December 31, 2019 by $13,220 and decreased during the year ended December 31, 2020 by $10,068. The decrease for the year ended December 31, 2020 is primarily attributed to the write-off of the Israel net operating loss carryforwards.

The Company follows the authoritative guidance on accounting for and disclosure of uncertainty in tax positions, which requires the Company to determine whether a tax position of the Company is more likely than not to be sustained upon examination, including resolution of any related appeals of litigation processes, based on the technical merits of the position. For tax positions meeting the more likely than not threshold, the tax amount recognized in the financial statements is reduced by the largest benefit that has a greater than 50% likelihood of being realized upon the ultimate settlement with the relevant taxing authority. As of December 31, 2020 the Company has not recorded any uncertain tax positions.

The Company files tax returns as prescribed by the tax laws of the jurisdictions in which it operates. In the normal course of business the Company is subject to examination by federal and state jurisdictions, where applicable. There are currently no pending tax examinations. The earliest tax years that may be subject to examination by jurisdiction are 2016 for both federal and state purposes. The Company’s policy is to record interest and penalties related to income taxes as part of the tax provision. There were no interest and penalties pertaining to uncertain tax positions for the years ended December 31, 2020 or 2019.

Net Loss Per Share

12 Months Ended

Dec. 31, 2020

Net Loss Per Share

Net Loss Per Share

11. Net Loss Per Share

Basic and diluted net loss per share for the years ended December 31, 2020 and 2019 was calculated as follows:



	Year Ended December 31,
	2020		2019
Numerator:
Net loss	$	(27,514)	$	(32,900)
Dividend attributable to down round feature of warrants		(303)		(359)
Dividend attributable to Series A & B convertible preferred stock		(372)		—
Series A & B convertible preferred stock - beneficial conversion feature		(9,399)		—
Net loss attributable to common stockholders for basic and diluted loss per share	$	(37,588)	$	(33,259)
Denominator:
Weighted average number of common shares outstanding - basic and diluted		59,327,713		22,582,687
Net loss per share attributable to common stockholders - basic and diluted	$	(0.63)	$	(1.47)

Included within weighted average common shares outstanding are 16,718,418 common shares issuable upon the exercise of the pre-funded warrants and penny warrants, as the warrants are exercisable at any time for nominal consideration, and as such, the shares are considered outstanding for the purpose of calculating basic and diluted net loss per share attributable to common stockholders.

The Company's potentially dilutive securities include RSUs, stock options and warrants. These securities were excluded from the computations of diluted net loss per share for the years ended December 31, 2020 and 2019, as the effect would be to reduce the net loss per share. The following table includes the potential common shares of common stock, presented based on amounts outstanding at each period end, that were excluded 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:


	Year Ended December 31,
	2020	2019
Restricted stock units to purchase common stock	753,106	90,500
Options to purchase common stock	6,393,853	4,024,566
Warrants to purchase common stock	35,986,317	10,369,752
	43,133,276	14,484,818

Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Dec. 31, 2020
Commitments and Contingencies
Commitments and Contingencies	12. Commitments and Contingencies Manufacturing Agreements—The Company is party to manufacturing agreements with vendors to manufacture DKN‑01, its lead product candidate, for use in clinical trials. As of December 31, 2020, noncancelable commitments under these agreements totaled $636. License and Service Agreements—On January 3, 2011, the Company entered into a license agreement with Eli Lilly and Company (“Lilly”), a shareholder, to grant a license to the Company for certain intellectual property rights relating to pharmaceutically active compounds that may be useful in the treatment of bone healing, cancer and, potentially, other medical conditions. As defined in the license agreement, the Company would be required to pay royalties to Lilly based upon a percentage in the low single digits of net sales of developed products, if and when achieved. However, there can be no assurance that clinical or commercialization success of developed products will occur, and no royalties have been paid or accrued through December 31, 2020. License Agreement—On May 28, 2015, the Company entered into a license agreement with Lonza Sales AG (“Lonza”), pursuant to which Lonza granted the Company a world-wide, non-exclusive license for certain intellectual property relating to a gene expression system for manufacturing DKN‑01. As defined in the license agreement, the Company would be required to pay royalties to Lonza based on a percentage in the low single digits of net sales of DKN‑01, if and when achieved. However, there can be no assurance that clinical or commercialization success will occur, and no royalties have been paid or accrued through December 31, 2020. Legal Proceedings—At each reporting date, the Company evaluates whether or not a potential loss amount or a potential range of loss is probable and reasonably estimable under the provisions of the authoritative guidance that addresses accounting for contingencies. The Company expenses as incurred the costs related to its legal proceedings. A patent covering the TRX518 antibody and its uses in methods of inducing or enhancing an immune response in a subject was granted in 2013 to the Company by the European Patent Office (EPO). Three notices of opposition to this patent were filed: two by major pharmaceutical companies and a third by an individual, possibly on behalf of a major pharmaceutical company. At the conclusion of the opposition proceedings before the Opposition Division of the EPO, the Opposition Division issued a decision indicating that the Company’s patent was maintained with modified claims that differ from the claims as originally granted. These narrowed claims cover the TRX518 antibody and uses of the TRX518 antibody in methods of inducing or enhancing an immune response in a subject. The Company filed an appeal of the decision of the Opposition Division seeking to obtain broader claims that more closely reflect the claims as granted in the patent. A hearing before the EPO Boards of Appeal took place on September 16, 2020, which resulted in the Boards of Appeal dismissing the appeal and maintaining the Decision of the Opposition Division. A written Decision by the Boards of Appeal was issued on September 25, 2020. In 2016, a patent covering the use of the TRX518 antibody in combination with a chemotherapeutic agent for treating cancer was granted to the Company by the EPO. In March 2017, notices of opposition to this patent were filed at the EPO by ten different entities, including several major pharmaceutical companies. Oral proceedings at the EPO took place on December 4 and 5, 2018. At the conclusion of the oral proceedings, the Opposition Division decided that the patent should be revoked in its entirety on the ground that the claims as granted contained added matter. Subsequently, the Opposition Division issued an interlocutory decision restating its conclusion that the claims as granted contained added matter and revoking the patent. The Company has filed an appeal of the decision of the Opposition Division seeking to obtain a reversal of the Opposition Division’s decision on added matter. The EPO Board of Appeal has not yet scheduled the appeal hearing. In December of 2019, a patent covering the use of the TRX518 antibody in combination with the chemotherapeutic agent, gemcitabine, for treating a colon tumor or adenocarcinoma of the colon, was granted to the Company by the EPO. A Notice of Opposition was filed against the patent by a single opponent, Sanofi, on September 25, 2020. The EPO issued a Communication on October 9, 2020 setting a deadline of February 9, 2021 for the Patentee to file a response to the Notice of Opposition. The Company filed a timely reply to the opponent's Notice of Opposition on February 9, 2021. Oral proceedings at the EPO have not yet been scheduled. Indemnification Agreements—In the ordinary course of business, the Company may provide indemnification of varying scope and terms to vendors, lessors, business partners and other parties with respect to certain matters including, but not limited to, losses arising out of breach of such agreements or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with members of its board of directors that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors or officers. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is, in many cases, unlimited. To date, the Company has not incurred any material costs as a result of such indemnifications. The Company is not aware of any claims under indemnification arrangements, and it has not accrued any liabilities related to such obligations in its consolidated financial statements as of December 31, 2020 and 2019.

Defined Contribution Plan	12 Months Ended
Defined Contribution Plan	Dec. 31, 2020
Defined Contribution Plan
Defined Contribution Plan	13. Defined Contribution Plan The Company has a 401(k) defined contribution plan (the "401(k) Plan") for substantially all of its employees. Eligible employees may make pretax contributions to the 401(k) Plan up to statutory limits. The Company makes matching employee contributions in cash to the 401(k) Plan at a rate of 100% of the first 3% of earnings contributed and 50% of the next 2% of earnings contributed. Employees participating in the 401(k) Plan are fully vested in the Company matching contributions, and investments are directed by participants. The Company made matching contributions of $195 and $170 for the years ended December 31, 2020 and 2019, respectively.

Related Party Transactions	12 Months Ended
Related Party Transactions	Dec. 31, 2020
Related Party Transactions
Related Party Transactions	14. Related Party Transactions The Company has a license agreement with a stockholder (See Note 12). On February 5, 2019, the Company completed the 2019 Public Offering pursuant to which the Company issued 7,557,142 shares of its common stock at a price of $1.75 per share, which included 985,714 shares issued pursuant to the underwriters’ exercise of their option to purchase additional shares of common stock, each share issued with a warrant to purchase one share of common stock. Each warrant has an exercise price of $1.95 per share with an exercise period expiring seven years from the date of issuance. The aggregate net proceeds received by the Company from the offering were approximately $12,122, net of underwriting discounts and commissions and estimated offering expenses payable by the Company. HealthCare Ventures IX, L.P. purchased common stock and warrants in the 2019 Public Offering on the same terms and conditions as the other Purchasers. Three of the Company’s directors and executive officers are affiliated with HealthCare Ventures IX, L.P. and its affiliates.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2020

Summary of Significant Accounting Policies

Principles of Consolidation

The accompanying consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany accounts and transactions are eliminated upon consolidation.

Use of Estimates

Cash and Cash Equivalents

The Company considers all highly liquid investments with maturities of three months or less when purchased to be cash equivalents.

Research and Development Expense

Research and development incentive income and receivable

The following table shows the change in the research and development incentive receivable from January 1, 2019 to December 31, 2020:


Balance at January 1, 2019	$	836
Australian research and development incentive income, net		132
Cash received for 2018 eligible expenses		(757)
Foreign currency translation		(26)
Balance at December 31, 2019		185
Australian research and development incentive income, net		231
Cash received for 2019 eligible expenses		(331)
Foreign currency translation		(12)
Balance at December 31, 2020	$	73

Concentration of Credit Risk

Income Taxes

Foreign Currency Translation

Property and Equipment

Impairment of Long-Lived Assets

Deferred Costs

As of December 31, 2020 and December 31, 2019 there was $345 and $831, respectively, of deferred costs.

Deposits

Warrants

Fair Value of Financial Instruments

Level 1—Quoted prices in active markets for identical assets or liabilities.

A summary of the assets and liabilities carried at fair value in accordance with the hierarchy defined above is as follows (in thousands):


	Total		Level 1		Level 2		Level 3
December 31, 2020
Assets:
Cash equivalents	$	51,116	$	51,116	$	—	$	—
Total assets	$	51,116	$	51,116	$	—	$	—

Liabilities:
Restricted stock liability	$	204	$	—	$	204	$	—
Total liabilities	$	204	$	—	$	204	$	—

December 31, 2019
Assets:
Cash equivalents	$	3,891	$	3,891	$	—	$	—
Total assets	$	3,891	$	3,891	$	—	$	—

Liabilities:
Restricted stock liability	$	159	$	—	$	159	$	—
Total liabilities	$	159	$	—	$	159	$	—

Leases

Segment Information

Patent Costs

Stock-Based Compensation

Stock-based compensation is classified in the accompanying consolidated statements of operations based on the function to which the related services are provided.

Revenue Recognition

Collaborative Arrangements

See Note 3 for a complete discussion of the revenue recognition for the Company's license agreement.

Net Loss per Share

Subsequent Events

Recent Accounting Pronouncements

From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board, or FASB, and are early adopted by the Company or adopted as of the specified effective date.

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2020

Summary of Significant Accounting Policies

Schedule of change in the research and development incentive receivable

The following table shows the change in the research and development incentive receivable from January 1, 2019 to December 31, 2020:


Balance at January 1, 2019	$	836
Australian research and development incentive income, net		132
Cash received for 2018 eligible expenses		(757)
Foreign currency translation		(26)
Balance at December 31, 2019		185
Australian research and development incentive income, net		231
Cash received for 2019 eligible expenses		(331)
Foreign currency translation		(12)
Balance at December 31, 2020	$	73

Summary of assets and liabilities carried at fair value in accordance with the hierarchy

A summary of the assets and liabilities carried at fair value in accordance with the hierarchy defined above is as follows (in thousands):


	Total		Level 1		Level 2		Level 3
December 31, 2020
Assets:
Cash equivalents	$	51,116	$	51,116	$	—	$	—
Total assets	$	51,116	$	51,116	$	—	$	—

Liabilities:
Restricted stock liability	$	204	$	—	$	204	$	—
Total liabilities	$	204	$	—	$	204	$	—

December 31, 2019
Assets:
Cash equivalents	$	3,891	$	3,891	$	—	$	—
Total assets	$	3,891	$	3,891	$	—	$	—

Liabilities:
Restricted stock liability	$	159	$	—	$	159	$	—
Total liabilities	$	159	$	—	$	159	$	—

BeiGene Exclusive Option and License Agreement (Tables)

12 Months Ended

Dec. 31, 2020

BeiGene Exclusive Option and License Agreement

Summary of activity in Company's contract liabilities


	Balance at						Balance at
	January 1, 2020		Additions		Revenue recognized		December 31, 2020
Total contract liabilities	$	—	$	3,000	$	(1,500)	$	1,500

Property and Equipment, Net (Tables)

12 Months Ended

Dec. 31, 2020

Property and Equipment, Net

Schedule of property and equipment, net


	December 31,
	2020		2019
Computer office equipment	$	51	$	51
Leasehold improvements		69		69
Lab equipment		76		113
Furnitures and fixtures		30		30
		226		263
Less: accumulated depreciation		(161)		(139)
Property and equipment, net	$	65	$	124

Accrued Expenses (Tables)

12 Months Ended

Dec. 31, 2020

Accrued Expenses

Schedule of accrued expenses


	December 31,
	2019		2018
Clinical trials	$	795	$	1,828
Professional fees		255		609
Payroll and related expenses		1,697		1,004
Accrued expenses	$	2,747	$	3,441

Leases (Tables)

12 Months Ended

Dec. 31, 2020

Leases

Schedule of future minimum lease payments


Future Operating Lease Payments
2021		434
2022		146
Total Lease Payments		580
Less: imputed interest		(28)
Total operating lease liabilities	$	552

Warrants (Tables)

12 Months Ended

Dec. 31, 2020

Warrants

Schedule of warrants


December 31, 2020
	Number of Shares
Date Exercisable	Issuable	Exercise Price
1/23/2017	54,516	$	0.01
11/14/2017	2,549,840	$	1.055
2/5/2019	7,491,442	$	1.95
3/5/2020	14,413,902	$	0.001
3/5/2020	25,945,035	$	2.11
6/22/2020	2,250,000	$	0.001
	52,704,735

Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2020

Stock-Based Compensation

Schedule of stock option activity under the Company's Equity Incentive Plans


		Weighted
		Average		Weighted	Aggregate
		Exercise Price		Average Remaining	Intrinsic
	Options	Per Share		Life in Years	Value
Outstanding at December 31, 2018	2,761,912	$	11.30	8.01	$	—
Granted	1,481,975	$	1.48
Forfeited	(219,321)	$	15.14
Outstanding at December 31, 2019	4,024,566	$	7.48	7.98	$	2
Granted	2,662,500	$	2.10
Exercised	(32,778)	$	1.53
Forfeited	(260,435)	$	6.95
Outstanding at December 31, 2020	6,393,853	$	5.29	7.96	$	1,961
Options exercisable at December 31, 2020	3,482,169	$	7.83	7.07	$	722
Options vested and expected to vest at December 31, 2020	6,393,853	$	5.29	7.96	$	1,961

Schedule of assumptions used to determine grant-date fair value of stock options


	Year Ended December 31,
	2020		2019
Expected volatility	66.94	%	66.94	%
Weighted average risk-free interest rate	0.66	%	2.07	%
Expected dividend yield	0.00	%	0.00	%
Expected term (in years)	6.85		6.77

Schedule of stock-based compensation expense related to issuance of stock option awards recognized in condensed consolidated statements of operations


	Year Ended
	December 31,
	2020		2019
Research and development	$	1,028	$	714
General and administrative		1,296		3,018
Total	$	2,324	$	3,732

Summary of outstanding RSU's under the 2016 Plan


		Weighted
	Number of	Average
	Shares	Fair Value
Outstanding at December 31, 2018	—	$	—
Awarded	181,000	$	1.74
Settled in cash	(90,500)	$	1.17
Outstanding at December 31, 2019	90,500	$	1.76
Awarded	753,106	$	1.49
Settled in cash	(90,500)	$	1.76
Outstanding at December 31, 2020	753,106	$	1.52

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2020

Income Taxes

Schedule of income (loss) before income taxes


	Year Ended
	December 31,
	2020		2019
U.S.	$	(28,699)	$	(32,875)
Foreign		1,183		(28)
Loss before income taxes	$	(27,516)	$	(32,903)

Schedule of Company's current and deferred expense for income tax


	Year Ended
	December 31,
	2020		2019
Current expense (benefit):
Federal	$	—	$	—
State		—		—
Foreign		40		—
Total current expense (benefit):	$	40	$	—
Deferred expense (benefit):
Federal	$	—	$	—
State		—		—
Foreign		(42)		(3)
Total deferred expense (benefit):	$	(42)	$	(3)
Total income tax expense (benefit):	$	(2)	$	(3)

Schedule of reconciliation of the Company's statutory income tax rate to the Company's effective income tax rate


	Year Ended
	December 31,
	2020		2019
Income at US Statutory Rate	21.00	%	21.00	%
State Taxes, net of Federal benefit	6.97	%	6.79	%
Permanent Differences	(1.09)	%	(0.33)	%
Tax Credits	5.98	%	3.30	%
Tax Law Change	(0.04)	%	0.00	%
Foreign Rate Differential	(0.46)	%	0.07	%
Israel DTA write-off	(70.15)	%	0.00	%
Valuation Allowance	36.56	%	(40.18)	%
Other	1.23	%	9.35	%
	0.00	%	0.00	%

Schedule of significant components of the Company's deferred tax assets


	Year Ended
	December 31,
	2020		2019
Accrued expenses		455		277
License Fees		1,168		1,332
Stock Options		3,759		2,584
Other		228		115
State net operating loss carryforwards		8,959		7,431
State research tax credits		625		510
Federal net operating loss carryforwards		33,711		47,845
Federal research tax credits		4,943		3,770
Total deferred tax assets		53,848		63,864
Valuation allowance		(53,669)		(63,737)
Net deferred tax asset (liability)		179		127

Net Loss Per Share (Tables)

12 Months Ended

Dec. 31, 2020

Net Loss Per Share

Schedule of basic and diluted net loss per share



	Year Ended December 31,
	2020		2019
Numerator:
Net loss	$	(27,514)	$	(32,900)
Dividend attributable to down round feature of warrants		(303)		(359)
Dividend attributable to Series A & B convertible preferred stock		(372)		—
Series A & B convertible preferred stock - beneficial conversion feature		(9,399)		—
Net loss attributable to common stockholders for basic and diluted loss per share	$	(37,588)	$	(33,259)
Denominator:
Weighted average number of common shares outstanding - basic and diluted		59,327,713		22,582,687
Net loss per share attributable to common stockholders - basic and diluted	$	(0.63)	$	(1.47)

Schedule of potentially anti-dilutive securities excluded from calculation of diluted net loss per share


	Year Ended December 31,
	2020	2019
Restricted stock units to purchase common stock	753,106	90,500
Options to purchase common stock	6,393,853	4,024,566
Warrants to purchase common stock	35,986,317	10,369,752
	43,133,276	14,484,818

Nature of Business, Basis of Presentation and Liquidity - Liquidity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Nature of Business, Basis of Presentation and Liquidity
Accumulated deficit	$ 222,985	$ 195,168
Net loss	27,514	32,900
Cash and cash equivalents	$ 52,071	$ 3,891

- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669619-108580

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=109239629&loc=SL4573702-111684

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669625-108580

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (c)(1)
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599

Reference 6: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 55
-Paragraph 4J
-URI http://asc.fasb.org/extlink&oid=116874947&loc=SL4591551-111686

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3000-108585

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 19
-URI http://asc.fasb.org/extlink&oid=108774443&loc=SL4569616-111683

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8933-108599

Reference 10: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 55
-Paragraph 4K
-URI http://asc.fasb.org/extlink&oid=116874947&loc=SL4591552-111686

+ Details

Summary of Significant Accounting Policies - Significant Accounting Policies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Accounting policies:
Eligible for reimbursement (as a percent of R&D expense)	43.50%	43.50%
Research and development incentive income and receivable
Balance at the beginning of the year	$ 185	$ 836
Australian research and development incentive income, net	231	132
Cash received for eligible expenses	(331)	(757)
Foreign currency translation	(12)	(26)
Balance at the end of the year	73	185
Other Assets
Deferred costs	345	831
Deposits	980	1,099
Uncertain tax positions	$ 0	0
Incremental borrowing rate	8.00%
Service agreements
Other Assets
Deposits	$ 980	$ 1,099
Computer equipment
Other Assets
Useful life (in years)	3 years
Lab equipment
Other Assets
Useful life (in years)	5 years
Computer office equipment
Other Assets
Useful life (in years)	5 years
Furnitures and fixtures
Other Assets
Useful life (in years)	5 years

Summary of Significant Accounting Policies - Warrants and Fair Value of Financial Instruments (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Jan. 01, 2019	Dec. 31, 2020	Dec. 31, 2019	Mar. 05, 2020	Jan. 31, 2019
Warrants
Warrant, equity component	$ 3,448		$ 3,448
Dividend attributable to down round feature of warrants		$ 303	359
Assets:
Cash equivalents		51,116	3,891
Total assets		51,116	3,891
Liabilities:
Restricted stock liability		204	159
Total liabilities		204	159
2019 Public Offering
Warrants
Dividend attributable to down round feature of warrants			$ 359
Exercise price of warrant			$ 1.75		$ 6.085
January 2020 Private Placement
Warrants
Dividend attributable to down round feature of warrants		$ 303
Exercise price of warrant		$ 1.055		$ 2.11	$ 1.75
Level 1
Assets:
Cash equivalents		$ 51,116	$ 3,891
Total assets		51,116	3,891
Level 2
Liabilities:
Restricted stock liability		204	159
Total liabilities		$ 204	$ 159

BeiGene Exclusive Option and License Agreement - Additional information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Jan. 03, 2020
BeiGene Exclusive Option and License Agreement
Up-front fee	$ 3,000
Revenue recognized	1,500
Contract acquisition costs	270
Amortization expense	135
Deferred Costs	135
Exclusive Option and License Agreement
BeiGene Exclusive Option and License Agreement
Upfront cash payment		$ 3,000
Future option exercise and milestone payments, maximum		$ 132,000
License Agreement
BeiGene Exclusive Option and License Agreement
Revenue recognized	1,500
Royalty
BeiGene Exclusive Option and License Agreement
Revenue recognized	$ 0

BeiGene Exclusive Option and License Agreement (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($)
Deferred revenue - current
Balance at December 31, 2020	$ 1,500
Total contract liabilities
Additions	3,000
Revenue recognized	(1,500)
Contract liabilities	$ 1,500

Property and Equipment, Net (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Property and Equipment, Net
Property and equipment, gross	$ 226	$ 263
Less: accumulated depreciation	(161)	(139)
Property and equipment, net	65	124
Depreciation expense	34	47
Computer office equipment
Property and Equipment, Net
Property and equipment, gross	51	51
Leasehold improvements
Property and Equipment, Net
Property and equipment, gross	69	69
Lab equipment
Property and Equipment, Net
Property and equipment, gross	76	113
Furnitures and fixtures
Property and Equipment, Net
Property and equipment, gross	$ 30	$ 30

Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Accrued Expenses
Clinical trials	$ 795	$ 1,828
Professional fees	255	609
Payroll and related expenses	1,697	1,004
Accrued expenses	$ 2,747	$ 3,441

Leases (Details) - USD ($) $ in Thousands	12 Months Ended
Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Right of use asset	$ 528	$ 1,026
Lease liability	552
Rent expense	$ 549	$ 837
Accounting Standards Update 2016-02 \| Restatement Adjustment
Right of use asset			$ 1,720
Lease liability			1,720
Reclassification of rent liability against right-of-use asset			$ 35

Leases - Future minimum lease payments (Details) $ in Thousands	Dec. 31, 2020 USD ($)
Leases
2021	$ 434
2022	146
Total Lease Payments	580
Less: imputed interest	(28)
Total operating lease liabilities	$ 552

Warrants (Details) $ / shares in Units, $ in Thousands						12 Months Ended
Warrants (Details) $ / shares in Units, $ in Thousands	Jun. 22, 2020 $ / shares shares	Mar. 05, 2020 $ / shares shares	Jan. 03, 2020 Vote item $ / shares shares	Feb. 05, 2019 $ / shares shares	Jan. 01, 2019 USD ($) $ / shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares
Warrants
Number of Shares Issuable						52,704,735
Warrant, equity component \| $					$ 3,448		$ 3,448
Dividend attributable to down round feature of warrants \| $						$ 303	$ 359
Common stock issued				7,557,142
Common Stock
Warrants
Common stock issued							7,557,142
Series A Convertible Preferred Stock
Warrants
Common stock issued						1,421,801
Series B Convertible Preferred Stock
Warrants
Common stock issued						1,137,442
2017 Warrants
Warrants
Exercise price of warrant \| $ / shares					$ 6.085	$ 1.055	$ 1.75
Warrant, equity component \| $					$ 3,448
Dividend attributable to down round feature of warrants \| $						$ 303	$ 359
Number of warrants or rights exercised						208,254
Class of Warrant or Right, Exercised \| $						$ 220
2019 Warrants
Warrants
Exercise price of warrant \| $ / shares				$ 1.95
Warrant to purchase shares of common stock				7,557,142
Number of warrants or rights exercised						65,700
Class of Warrant or Right, Exercised \| $						$ 128
January 2020 Warrants \| Series A Convertible Preferred Stock
Warrants
Exercise price of warrant \| $ / shares		$ 0.001
Warrant to purchase shares of common stock		14,413,902
Common stock issued			1,421,801
Purchase price \| $ / shares			$ 10.54
Number of special voting stock \| Vote			1
Number of members to elect of board of directors \| item			1
January 2020 Warrants \| Series B Convertible Preferred Stock
Warrants
Exercise price of warrant \| $ / shares		$ 2.11
Common stock issued			1,137,442
Purchase price \| $ / shares			$ 10.55
Conversion of Stock, Shares Issued		11,531,133
June 2020 Warrants
Warrants
Exercise price of warrant \| $ / shares	$ 0.001
Warrant to purchase shares of common stock	2,250,000
June 2020 Warrants \| Common Stock
Warrants
Common stock issued	20,250,000
Purchase price \| $ / shares	$ 2.00
1/23/2017
Warrants
Number of Shares Issuable						54,516
Exercise price of warrant \| $ / shares						$ 0.01
11/14/2017
Warrants
Number of Shares Issuable						2,549,840
Exercise price of warrant \| $ / shares						$ 1.055
2/5/2019
Warrants
Number of Shares Issuable						7,491,442
Exercise price of warrant \| $ / shares						$ 1.95
3/5/2020
Warrants
Number of Shares Issuable						14,413,902
Exercise price of warrant \| $ / shares						$ 0.001
3/5/2020
Warrants
Number of Shares Issuable						25,945,035
Exercise price of warrant \| $ / shares						$ 2.11
6/22/2020
Warrants
Number of Shares Issuable						2,250,000
Exercise price of warrant \| $ / shares						$ 0.001

Common Stock - Public Offering (Details) $ / shares in Units, $ in Thousands					12 Months Ended
	Jun. 25, 2020 USD ($) shares	Jun. 22, 2020 $ / shares shares	Jul. 11, 2019 USD ($) $ / shares shares	Feb. 05, 2019 USD ($) item $ / shares shares	Dec. 31, 2020 USD ($) Vote $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares
Common stock, par value (in dollars per share) \| $ / shares					$ 0.001	$ 0.001
Issuance of common stock (value) \| $				$ 12,122		$ 12,122
Common stock issued \| shares				7,557,142
Price per share (in dollars per share) \| $ / shares				$ 1.75
Proceeds from issuance of common stock from ATM sales \| $						1,923
Proceeds from issuance of common stock in connection with July 2019 Lincoln Park Capital Registered Offering Purchase Agreement, net of issuance costs \| $						1,000
Number of Vote on Common Shares \| Vote					1
Dividends, Common Stock \| $					$ 0
2019 Warrants
Exercise price of warrant \| $ / shares				$ 1.95
Warrant to purchase shares of common stock \| shares				7,557,142
Warrants and Rights Outstanding, Term				7 years
Number of share for warrant to purchase of common stock \| item				1
June 2020 Warrants
Exercise price of warrant \| $ / shares		$ 0.001
Warrant to purchase shares of common stock \| shares		2,250,000
Distribution Agreement
Common stock issued \| shares					1,033,147
Commons Stock Value Maximum Right To Sell \| $					$ 30,000
Proceeds from issuance of common stock from ATM sales \| $					$ 1,923
Lincoln Park Purchase Agreements
Common stock, par value (in dollars per share) \| $ / shares			$ 0.001
Common stock issued \| shares			571,429
Price per share (in dollars per share) \| $ / shares			$ 1.75
Commons Stock Value Maximum Right To Sell \| $			$ 20,000
Stock Issued During Period, Shares, Issued for Services \| shares			330,000
Proceeds from issuance of common stock in connection with July 2019 Lincoln Park Capital Registered Offering Purchase Agreement, net of issuance costs \| $			$ 1,000
Underwriters' exercise
Common stock issued \| shares				985,714
Common Stock
Issuance of common stock (value) \| $						$ 7
Common stock issued \| shares						7,557,142
Common Stock \| June 2020 Warrants
Common stock issued \| shares		20,250,000
Share Price \| $ / shares		$ 2.00
Net proceeds from issuance of common stock \| $	$ 48,276
Common Stock \| Underwriters' exercise \| June 2020 Warrants
Common stock issued \| shares	3,375,000

Common Stock - Private Placement of Common Stock (Details) $ / shares in Units, $ in Thousands			12 Months Ended
	Jan. 03, 2020 USD ($) Vote item $ / shares shares	Feb. 05, 2019 $ / shares shares	Dec. 31, 2020 USD ($) $ / shares	Mar. 05, 2020 $ / shares shares	Dec. 31, 2019 $ / shares	Jan. 31, 2019 $ / shares
Private Placement of Common Stock
Common stock issued \| shares		7,557,142
Price per share (in dollars per share)		$ 1.75
Common Stock, Par or Stated Value Per Share			$ 0.001		$ 0.001
January 2020 Private Placement
Private Placement of Common Stock
Exercise price of warrant			$ 1.055	$ 2.11		$ 1.75
Fixed cumulative percentage per annum			8.00%
Cumulative Dividends \| $			$ 372
Series A Preferred \| January 2020 Private Placement
Private Placement of Common Stock
Common stock issued \| shares	1,421,801
Price per share (in dollars per share)	$ 10.54
Net proceeds from issuance of stock in private placement \| $	$ 25,322
Convertible Preferred Stock, Shares Issued upon Conversion \| shares				14,413,902
Common Stock, Par or Stated Value Per Share				$ 0.001
Value of beneficial conversion features \| $	$ 5,226
Number of special voting stock \| Vote	1
Number of members to elect of board of directors \| item	1
Series B Preferred \| January 2020 Private Placement
Private Placement of Common Stock
Common stock issued \| shares	1,137,442
Price per share (in dollars per share)	$ 10.55
Convertible Preferred Stock, Shares Issued upon Conversion \| shares				11,531,133
Common Stock, Par or Stated Value Per Share				$ 0.001
Value of beneficial conversion features \| $	$ 4,173

Stock-Based Compensation - Equity Incentive Plans (Details) - 2016 Plan - shares		12 Months Ended
	Jan. 20, 2017	Dec. 31, 2020	Dec. 31, 2019
Stock-Based Compensation
Annual increase (as percent of outstanding common stock)	4.00%
Number of options or stock awards available for grant under the Plan		340,144
Common Stock
Stock-Based Compensation
Additional shares authorized (in shares)			3,000,000
Restricted Stock Units (RSUs)
Stock-Based Compensation
Number of options issued under the plan		92,500	181,000

Stock-Based Compensation - Stock options (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Options
Outstanding balance at the beginning of the period (in shares)	4,024,566	2,761,912
Granted (in shares)	2,662,500	1,481,975
Exercised (in shares)	(32,778)
Forfeited (in shares)	(260,435)	(219,321)
Outstanding balance at the end of the period (in shares)	6,393,853	4,024,566	2,761,912
Options exercisable at the end of the period (in shares)	3,482,169
Options vested and expected to vest at end of period (in shares)	6,393,853
Weighted Average Exercise Price Per Share
Outstanding balance at the beginning of the period (in dollars per share)	$ 7.48	$ 11.30
Granted (in dollars per share)	2.10	1.48
Exercised (in dollars per share)	1.53
Forfeited (in dollars per share)	6.95	15.14
Outstanding balance at the end of the period (in dollars per share)	5.29	$ 7.48	$ 11.30
Exercisable at the end of the period (in dollars per share)	7.83
Options vested and expected to vest at end of the period (in dollars per share)	$ 5.29
Weighted Average Remaining Life in Years
Outstanding balance	7 years 11 months 16 days	7 years 11 months 23 days	8 years 4 days
Options exercisable at end of period	7 years 26 days
Options vested and expected to vest at end of the period	7 years 11 months 16 days
Aggregate Intrinsic Value
Outstanding balance	$ 1,961	$ 2
Options exercisable at the end of the period	722
Options vested and expected to vest at end of the period	1,961
Stock-based compensation expense	2,572	3,732
Stock-based compensation	$ 2,324	$ 3,732
Assumptions used to determine grant-date fair value
Expected Volatility	66.94%	66.94%
Weighted average risk-free interest rate	0.66%	2.07%
Expected dividend yield (as a percentage)	0.00%	0.00%
Expected term (in years)	6 years 10 months 6 days	6 years 9 months 7 days
Expiration period	10 years
Unrecognized costs	$ 3,947
Research and development
Aggregate Intrinsic Value
Stock-based compensation expense	1,028	$ 714
General and administrative
Aggregate Intrinsic Value
Stock-based compensation expense	$ 1,296	$ 3,018
Weighted average
Assumptions used to determine grant-date fair value
Weighted average period for recognition of compensation cost	2 years 29 days
Minimum
Assumptions used to determine grant-date fair value
Vesting period	3 years
Maximum
Assumptions used to determine grant-date fair value
Vesting period	4 years

Stock-Based Compensation - Outstanding RSU's under the 2016 Plan (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended			12 Months Ended
	Jan. 31, 2021	Jan. 31, 2020	Oct. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Weighted Average Fair Value
Restricted stock liability				$ 204	$ 159
Restricted Stock Units (RSUs)
Number of Shares
Settled in cash	(92,500)	(90,500)	(90,500)
Weighted Average Fair Value
Fair value				1,112
Unrecognized costs				$ 690
Unrecognized costs weighted-average period				2 years 2 months 16 days
Stock-based compensation expense				$ 204	$ 265
Restricted Stock Units (RSUs) \| Executive Officer [Member]
Number of Shares
Awarded				660,606
Weighted Average Fair Value
Vesting period				3 years
Stock-based compensation expense				$ 248
2016 Plan \| Restricted Stock Units (RSUs)
Number of Shares
Outstanding at the beginning	753,106	90,500		90,500
Awarded				753,106	181,000
Settled in cash				(90,500)	(90,500)
Outstanding at the end				753,106	90,500
Weighted Average Fair Value
Outstanding at the beginning (in dollars per share)	$ 1.52	$ 1.76		$ 1.76
Awarded (in dollars per share)				1.49	$ 1.74
Settled in cash (in dollars per share)				1.76	1.17
Outstanding at the end (in dollars per share)				$ 1.52	$ 1.76

Income Taxes - Operating Loss Carryforwards (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($)
Federal
Operating Loss Carryforwards
Operating loss carryforward	$ 160,531
Research tax credits	3,770
State
Operating Loss Carryforwards
Operating loss carryforward	141,751
Research tax credits	645
Foreign
Operating Loss Carryforwards
Indefinite federal net operating loss carryforward	$ 79,223

Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
Income Taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Income (Loss) before income taxes
U.S.	$ (28,699)	$ (32,875)
Foreign	1,183	(28)
Loss before income taxes	$ (27,516)	$ (32,903)

Income Taxes - Current and deferred expense for income tax (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Current expense (benefit):
Foreign	$ 40
Total current expense (benefit):	40
Deferred expense (benefit):
Foreign	(42)	$ (3)
Total deferred expense (benefit):	(42)	(3)
Total income tax expense (benefit):	$ (2)	$ (3)

Income Taxes - Reconciliation of Statutory and Effective Tax Rates (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Reconciliation of the statutory tax rate to the Company's effective tax rate
Income at US Statutory Rate	21.00%	21.00%
State Taxes, net of Federal benefit	6.97%	6.79%
Permanent Differences	(1.09%)	(0.33%)
Tax Credits	5.98%	3.30%
Tax Law change	(0.04%)	0.00%
Foreign Rate Differential	(0.46%)	0.07%
Israel DTA write-off	(70.15%)	0.00%
Valuation Allowance	36.56%	(40.18%)
Other	1.23%	9.35%
Effective income tax rate	0.00%	0.00%

Income Taxes - Components of Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred Tax Assets
Accrued expenses	$ 455	$ 277
License fees	1,168	1,332
Stock Options	3,759	2,584
Other	228	115
State net operating loss carryforwards	8,959	7,431
Federal net operating loss carryforwards	33,711	47,845
Total deferred tax assets	53,848	63,864
Valuation allowance	(53,669)	(63,737)
Net deferred tax asset (liability)	179	127
Federal
Deferred Tax Assets
Research tax credits	4,943	3,770
State
Deferred Tax Assets
Research tax credits	$ 625	$ 510

Income Taxes - Valuation Allowance and Tax Reforms (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Taxes
Increase/decreased in valuation allowance	$ 10,068	$ 13,220
Interest and penalties pertaining to uncertain tax positions	$ 0	$ 0

Net Loss Per Share - Basic and Diluted (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Numerator:
Net loss	$ (27,514)	$ (32,900)
Dividend attributable to down round feature of warrants	(303)	(359)
Dividend attributable to Series A & B convertible preferred stock	(372)
Series A & B convertible preferred stock - beneficial conversion feature	(9,399)
Net loss attributable to common stockholders for diluted loss per share	$ (37,588)	$ (33,259)
Denominator:
Weighted average number of common shares outstanding - basic and diluted (in shares)	59,327,713	22,582,687
Net loss per share attributable to common stockholders - basic and diluted (in dollars per share)	$ (0.63)	$ (1.47)
Exercise of the pre-funded warrants and penny warrants	16,718,418

Net Loss Per Share - Antidilutive (Details) - shares	12 Months Ended
Net Loss Per Share - Antidilutive (Details) - shares	Dec. 31, 2020	Dec. 31, 2019
Securities excluded from computation of diluted net loss per share
Anti-dilutive securities excluded from calculation of diluted net loss per share	43,133,276	14,484,818
Restricted Stock Units (RSUs)
Securities excluded from computation of diluted net loss per share
Anti-dilutive securities excluded from calculation of diluted net loss per share	753,106	90,500
Options to purchase common stock
Securities excluded from computation of diluted net loss per share
Anti-dilutive securities excluded from calculation of diluted net loss per share	6,393,853	4,024,566
Warrants to purchase common stock
Securities excluded from computation of diluted net loss per share
Anti-dilutive securities excluded from calculation of diluted net loss per share	35,986,317	10,369,752

Commitments and Contingencies - Manufacturing, License and Other Agreements (Details) $ in Thousands	Dec. 31, 2020 USD ($)
Commitments and Contingencies
Manufacturing commitments	$ 636
License And Service Agreements
Commitments and Contingencies
Royalties paid or accrued	0
Licensing Agreement
Commitments and Contingencies
Royalties paid or accrued	$ 0

Commitments and Contingencies - Legal Proceedings (Details)	1 Months Ended	12 Months Ended
	Mar. 31, 2017 entity	Dec. 31, 2020 company claim
Commitments and Contingencies
Number filing notice of opposition	10	2
Notices of opposition		3

Defined Contribution Plan (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Defined Contribution Plan
Contributions to the 401(k) Plan	$ 195	$ 170
Layering first
Defined Contribution Plan
Eligible Employees to contribute (as a percent)	3.00%
Company's match (as a percent)	100.00%
Layering second
Defined Contribution Plan
Eligible Employees to contribute (as a percent)	2.00%
Company's match (as a percent)	50.00%

Related Party Transactions (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Feb. 05, 2019	Dec. 31, 2019
Related Party Transactions
Issuance of Series A & B Convertible Preferred Stock, net of underwriting discounts (in shares)	7,557,142
Price per share (in dollars per share)	$ 1.75
Number of warrants issued per common stock	1
Issuance of common stock (value)	$ 12,122	$ 12,122
Underwriters' exercise
Related Party Transactions
Issuance of Series A & B Convertible Preferred Stock, net of underwriting discounts (in shares)	985,714
2019 Warrants
Related Party Transactions
Exercise price (per warrant)	$ 1.95
Warrant expiring period	7 years