Axsome Therapeutics (AXSM) 10-Q 5 Nov 20 2020 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2020	Oct. 30, 2020
Document and Entity Information [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Sep. 30, 2020
Entity File Number	001-37635
Entity Registrant Name	AXSOME THERAPEUTICS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	45-4241907
Entity Address, Address Line One	22 Cortlandt Street
Entity Address, Address Line Two	16th Floor
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10007
City Area Code	212
Local Phone Number	332-3241
Title of 12(b) Security	Common Stock, Par Value $0.0001 Per Share
Trading Symbol	AXSM
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Shell Company	false
Entity Ex Transition Period	true
Entity Common Stock, Shares Outstanding		37,344,201
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Entity Central Index Key	0001579428
Amendment Flag	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Current assets:
Cash	$ 202,360,292	$ 219,966,167
Prepaid and other current assets	911,992	413,095
Total current assets	203,272,284	220,379,262
Equipment, net	39,745	30,623
Other assets	317,375	139,875
Total assets	203,629,404	220,549,760
Current liabilities:
Accounts payable	11,315,126	10,943,325
Accrued expenses and other current liabilities	9,026,412	10,949,128
Loan payable, current portion		2,602,292
Total current liabilities	20,341,538	24,494,745
Loan payable, long-term	48,026,108	17,332,626
Total liabilities	68,367,646	41,827,371
Stockholders' equity:
Preferred stock, $0.0001 par value per share (10,000,000 shares authorized, none issued and outstanding at March 31, 2020 and December 31, 2019, respectively)
Common stock, $0.0001 par value per share (150,000,000 shares authorized, 37,075,422 and 36,933,217 shares issued and outstanding at March 31, 2020 and December 31, 2019, respectively)	3,733	3,693
Additional paid-in capital	384,889,471	354,614,189
Accumulated deficit	(249,631,446)	(175,895,493)
Total stockholders' equity	135,261,758	178,722,389
Total liabilities and stockholders' equity	$ 203,629,404	$ 220,549,760

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	37,344,201	36,933,217
Common stock, shares outstanding	37,334,201	36,933,217

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Operating expenses:
Research and development	$ 14,795,493	$ 15,835,573	$ 52,859,850	$ 34,441,796
General and administrative	6,331,308	3,111,662	18,537,242	8,375,131
Total operating expenses	21,126,801	18,947,235	71,397,092	42,816,927
Loss from operations	(21,126,801)	(18,947,235)	(71,397,092)	(42,816,927)
Interest income (expense)	(551,002)	(327,825)	(1,091,849)	(860,723)
Tax credit		139,448		139,448
Loss on extinguishment of debt	(1,247,012)		(1,247,012)
Net loss	$ (22,924,815)	$ (19,135,612)	$ (73,735,953)	$ (43,538,202)
Net loss per common share, basic and diluted	$ (0.61)	$ (0.56)	$ (1.98)	$ (1.29)
Weighted average common shares outstanding, basic and diluted	37,311,726	34,445,489	37,158,513	33,771,671

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($)	Common Stock	Additional paid-in capital	Accumulated deficit	Total
Beginning balance at Dec. 31, 2018	$ 3,009	$ 108,485,219	$ (107,550,307)	$ 937,921
Balance (in shares) at Dec. 31, 2018	30,087,213
Stock-based compensation		1,256,310		1,256,310
Issuance of common stock upon exercise of options	$ 5	410,157		410,162
Issuance of common stock upon exercise of options (in shares)	52,819
Issuance of warrants upon debt financing		426,000		426,000
Issuance of common stock upon financing	$ 316	24,983,366		24,983,682
Issuance of common stock upon financing (in shares)	3,164,015
Net loss			(10,640,376)	(10,640,376)
Ending balance at Mar. 31, 2019	$ 3,330	135,561,052	(118,190,683)	17,373,699
Balance (in shares) at Mar. 31, 2019	33,304,047
Beginning balance at Dec. 31, 2018	$ 3,009	108,485,219	(107,550,307)	937,921
Balance (in shares) at Dec. 31, 2018	30,087,213
Net loss				(43,538,202)
Ending balance at Sep. 30, 2019	$ 3,450	157,907,655	(151,088,509)	6,822,596
Balance (in shares) at Sep. 30, 2019	34,496,846
Beginning balance at Mar. 31, 2019	$ 3,330	135,561,052	(118,190,683)	17,373,699
Balance (in shares) at Mar. 31, 2019	33,304,047
Stock-based compensation		888,556		888,556
Issuance of common stock upon exercise of options	$ 6	205,330		205,336
Issuance of common stock upon exercise of options (in shares)	59,720
Issuance of common stock upon exercise of warrants	$ 2	144,868		144,870
Issuance of common stock upon exercise of warrants (in shares)	24,389
Issuance of warrants upon debt financing		(39,000)		(39,000)
Issuance of common stock upon financing	$ 95	19,471,603		19,471,698
Issuance of common stock upon financing (in shares)	942,285
Net loss			(13,762,214)	(13,762,214)
Ending balance at Jun. 30, 2019	$ 3,433	156,232,409	(131,952,897)	24,282,945
Balance (in shares) at Jun. 30, 2019	34,330,441
Stock-based compensation		1,156,435		1,156,435
Issuance of common stock upon exercise of options	$ 13	483,825		483,838
Issuance of common stock upon exercise of options (in shares)	129,218
Issuance of common stock upon exercise of warrants	$ 4	34,986		34,990
Issuance of common stock upon exercise of warrants (in shares)	37,187
Net loss			(19,135,612)	(19,135,612)
Ending balance at Sep. 30, 2019	$ 3,450	157,907,655	(151,088,509)	6,822,596
Balance (in shares) at Sep. 30, 2019	34,496,846
Beginning balance at Dec. 31, 2019	$ 3,693	354,614,189	(175,895,493)	$ 178,722,389
Balance (in shares) at Dec. 31, 2019	36,933,217			36,933,217
Stock-based compensation		2,133,530		$ 2,133,530
Issuance of common stock upon exercise of options	$ 6	629,750		629,756
Issuance of common stock upon exercise of options (in shares)	60,186
Issuance of common stock upon financing	$ 8	7,155,329		7,155,337
Issuance of common stock upon financing (in shares)	82,019
Net loss			(32,484,146)	(32,484,146)
Ending balance at Mar. 31, 2020	$ 3,707	364,532,798	(208,379,639)	156,156,866
Balance (in shares) at Mar. 31, 2020	37,075,422
Beginning balance at Dec. 31, 2019	$ 3,693	354,614,189	(175,895,493)	$ 178,722,389
Balance (in shares) at Dec. 31, 2019	36,933,217			36,933,217
Issuance of common stock upon exercise of options (in shares)				123,456
Net loss				$ (73,735,953)
Ending balance at Sep. 30, 2020	$ 3,733	384,889,471	(249,631,446)	$ 135,261,758
Balance (in shares) at Sep. 30, 2020	37,344,201			37,344,201
Beginning balance at Mar. 31, 2020	$ 3,707	364,532,798	(208,379,639)	$ 156,156,866
Balance (in shares) at Mar. 31, 2020	37,075,422
Stock-based compensation		4,148,025		4,148,025
Issuance of common stock upon exercise of options	$ 2	190,407		190,409
Issuance of common stock upon exercise of options (in shares)	20,428
Issuance of common stock upon exercise of warrants	$ 3			3
Issuance of common stock upon exercise of warrants (in shares)	29,982
Issuance of warrants upon debt financing (in shares)	141,678
Issuance of common stock upon financing	$ 14	12,074,985		12,074,999
Net loss			(18,326,992)	(18,326,992)
Ending balance at Jun. 30, 2020	$ 3,726	380,946,215	(226,706,631)	154,243,310
Balance (in shares) at Jun. 30, 2020	37,267,510
Stock-based compensation		2,868,818		2,868,818
Issuance of common stock upon exercise of options	$ 4	190,222		190,226
Issuance of common stock upon exercise of options (in shares)	42,842
Issuance of common stock upon exercise of warrants	$ 3			3
Issuance of common stock upon exercise of warrants (in shares)	33,849
Issuance of warrants upon debt financing		884,216		884,216
Net loss			(22,924,815)	(22,924,815)
Ending balance at Sep. 30, 2020	$ 3,733	$ 384,889,471	$ (249,631,446)	$ 135,261,758
Balance (in shares) at Sep. 30, 2020	37,344,201			37,344,201

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($)	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Cash flows from operating activities
Net loss	$ (73,735,953)	$ (43,538,202)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	9,150,373	3,301,301
Non-cash research and development license expense	7,155,337
Amortization of debt discount	491,009	471,742
Loss on extinguishment of debt	1,247,012
Depreciation	16,482	31,938
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(498,897)	652,015
Other assets	(177,500)	(56,624)
Accounts payable	371,801	5,760,114
Accrued expenses and other current liabilities	(1,922,716)	4,569,808
Net cash used in operating activities	(57,903,052)	(28,807,908)
Cash flows from investing activities
Purchases of equipment	(25,604)	(14,660)
Net cash used in investing activities	(25,604)	(14,660)
Cash flows from financing activities
Procceds from issuance of common stock upon financing, net	12,074,999	44,455,380
Proceeds from issuance of term loan	50,000,000	20,000,000
Payment of debt financing costs	(1,102,609)
Repayment of principal on term loan	(21,660,000)	(7,238,889)
Proceeds from issuance of common stock upon exercise of options	1,010,391	1,099,336
Proceeds issuance of common stock upon exercise of warrants		179,860
Net cash (used in) provided by financing activities	40,322,781	58,495,687
Net (decrease) increase in cash	(17,605,875)	29,673,119
Cash at beginning of period	219,966,167	13,968,742
Cash at end of period	202,360,292	43,641,861
Supplemental disclosures of cash flow information:
Interest paid	1,179,337	979,167
Supplemental disclosures of non-cash financing activity:
Issuance of warrants in connection with debt financing	884,216	$ 387,000
Shares of common stock issued in connection with license agreement with Pfizer, Inc.	$ 8,000,000

Nature of Business and Basis of

Nature of Business and Basis of Presentation	9 Months Ended
	Sep. 30, 2020
Nature of Business and Basis of Presentation
Nature of Business and Basis of Presentation	Note 1. Nature of Business and Basis of Presentation Axsome Therapeutics, Inc. (“Axsome” or the “Company”) is a biopharmaceutical company developing novel therapies for central nervous system (“CNS”) disorders for which there are limited treatment options. By focusing on this therapeutic area, the Company is addressing significant and growing markets where current treatment options are limited or inadequate. The Company’s core CNS portfolio includes five product candidates, AXS-05, AXS-07, AXS-09, AXS-12, and AXS-14, which are being developed for multiple indications. The Company aims to become a fully integrated biopharmaceutical company that develops and commercializes differentiated therapies that expand the treatment options available to caregivers and improve the lives of patients living with CNS disorders. The Company was incorporated on January 12, 2012 in the State of Delaware. The accompanying unaudited interim consolidated financial statements have been prepared by the Company in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”) for interim information and pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”) for reporting on Form 10-Q. Accordingly, certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to such rules and regulations. These unaudited interim consolidated financial statements should be read in conjunction with the audited financial statements and related notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2019 filed with the SEC on March 12, 2020. In the opinion of management, the unaudited interim consolidated financial statements reflect all adjustments, which are normal recurring adjustments, necessary for the fair presentation of the financial information for the interim periods. The results of operations for the three and nine months ended September 30, 2020 are not necessarily indicative of the operating results for the full fiscal year or any future period. Liquidity and Capital Resources The Company has incurred operating losses since its inception, and expects to continue to incur operating losses for the foreseeable future and may never become profitable. As of September 30, 2020, the Company had an accumulated deficit of $249.6 million. The Company’s primary sources of cash have been proceeds from the issuance and sale of its common stock in public offerings. The Company has not yet commercialized any of its product candidates and cannot be sure if it will ever be able to do so. The Company’s ability to achieve profitability depends on a number of factors, including its ability to obtain regulatory approval for its product candidates, successfully complete any post-approval regulatory obligations and successfully commercialize its product candidates alone or in partnership. The Company may continue to incur substantial operating losses even if it begins to generate revenues from its product candidates. The Company believes its existing cash will be sufficient to fund its anticipated operating cash requirements for at least twelve months following the date of this filing. The actual amount of cash that the Company will need to operate is subject to many factors, including, but not limited to, the timing, design and conduct of clinical trials for its product candidates. The Company may use a combination of public and private equity offerings, debt financings, other third-party funding, strategic alliances, licensing arrangements or marketing and distribution arrangements if market conditions are favorable or in light of other strategic considerations to finance its future cash needs. The Company’s common stock is listed on Impact of COVID-19 In December 2019, a novel (new) coronavirus known as SARS-CoV-2 was first detected in Wuhan, Hubei Province, People’s Republic of China, causing outbreaks of the coronavirus disease, known as COVID-19, that has now spread globally. On January 30, 2020, the World Health Organization (WHO) declared COVID-19 a public health emergency. The Secretary of Health and Human Services declared a public health emergency in the United States on January 31, 2020, under section 319 of the Public Health Service Act (42 U.S.C. 247d), in response to the COVID-19 outbreak. On March 11, 2020, the WHO declared COVID-19 a pandemic. The full impact of the COVID-19 pandemic is unknown and rapidly evolving. While the potential economic impact brought by and over the duration of the COVID-19 pandemic may be difficult to assess or predict, the COVID-19 pandemic has resulted in significant disruption of global financial markets, which could in the future negatively affect the Company’s liquidity. In addition, a recession or market volatility resulting from the COVID-19 pandemic could affect the Company’s business. Given the nature and type of the Company’s short-term investments, the Company does not believe the COVID-19 pandemic has had or will have a material impact on the Company’s current investment liquidity.

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2020
Summary of Significant Accounting Policies
Summary of Significant Accounting Policies	Note 2. Summary of Significant Accounting Policies Significant Risks and Uncertainties The Company’s operations are subject to a number of factors that can affect its operating results and financial condition. Such factors include, but are not limited to: the results of clinical testing and trial activities of the Company’s product candidates; the Company’s ability to obtain regulatory approval to market its products, if approved; competition from products manufactured and sold or being developed by other companies; the price of, and demand for, the Company’s products, if approved; the Company’s ability to negotiate favorable licensing or other manufacturing and marketing agreements for its products, if approved; and the Company’s ability to raise additional financing. If the Company does not successfully commercialize any of its product candidates, it will be unable to generate recurring product revenue or achieve and maintain profitability. Use of Estimates Management considers many factors in developing the estimates and assumptions that are used in the preparation of these financial statements. Management must apply significant judgment in this process. In addition, other factors may affect estimates, including expected business and operational changes, sensitivity and volatility associated with the assumptions used in developing estimates, and whether historical trends are expected to be representative of future trends. The estimation process often may yield a range of potentially reasonable estimates of the ultimate future outcomes and management must select an amount that falls within that range of reasonable estimates. This process may result in actual results differing materially from those estimated amounts used in the preparation of the financial statements if these results differ from historical experience, or other assumptions do not turn out to be substantially accurate, even if such assumptions are reasonable when made. In preparing these financial statements, management used significant estimates in the following areas, among others: stock-based compensation expense; the determination of the fair value of the warrants; the accounting for research and development costs; and the recoverability of the Company’s net deferred tax assets and related valuation allowance. Foreign Currency Translation Expenses denominated in foreign currency are translated into U.S. dollars at the exchange rate on the date the expense is incurred. Assets and liabilities of foreign operations are translated at period-end exchange rates. The effect of exchange rate fluctuations on translating foreign currency into U.S. dollars is included in the Statements of Operations and is not material to the Company’s financial statements. Segment and Geographic Information Operating segments are defined as components of an enterprise for which separate discrete information is available for evaluation by the chief operating decision maker or decision-making group, in deciding how to allocate resources and in assessing performance. The Company views its operations and manages its business as one operating segment, which is the business of developing novel therapies for the management of CNS disorders. Cash Equivalents The Company considers all highly liquid investments that have maturities of three months or less when acquired to be cash equivalents. The Company’s cash and cash equivalents includes holdings in checking and overnight sweep accounts. The Company’s cash equivalents, which are money market funds held in a sweep account, are measured at fair value on a recurring basis. As of September 30, 2020, the balance of cash and cash equivalents was $202.4 million, which approximates fair value and was determined based upon Level 1 inputs. The sweep account is valued using quoted market prices with no valuation adjustments applied. Accordingly, these securities are categorized as Level 1. Concentration of Credit Risk Fair Value of Financial Instruments 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 at the measurement date. Assets and liabilities that are measured at fair value are reported using a three-level fair value hierarchy that prioritizes the inputs used to measure fair value. This hierarchy maximizes the use of observable inputs and minimizes the use of unobservable inputs. The three levels of inputs used to measure fair value are as follows: Level 1 Level 2 Level 3 To the extent that valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. Debt Issuance Costs Debt issuance costs consist of costs incurred in obtaining long-term financing. These costs are classified on the consolidated balance sheet as a direct deduction from the carrying amount of the related debt liability. These expenses are deferred and amortized as part of interest expense in the consolidated statement of operations using the effective interest rate method over the term of the debt agreement. Equipment Equipment consists primarily of computer equipment and is recorded at cost. Equipment is depreciated on a straight-line basis over its estimated useful life, which the Company estimates to be three years . When equipment is sold or otherwise disposed of, the cost and related accumulated depreciation are removed from the accounts and the resulting gain or loss is included in operating expenses. Research and Development Costs Research and development expenses primarily consist of costs incurred in performing research and development activities, including preclinical studies, clinical trials, manufacturing costs, regulatory costs, employee salaries and benefits, stock-based compensation expense, contract services, including external research and development expenses incurred under arrangements with third parties, such as contract research organizations (“CROs”), facilities costs, overhead costs, depreciation, and other related costs. Generally, research and development costs are expensed as incurred. Nonrefundable advance payments for goods or services that will be used or rendered for future research and development activities are deferred and amortized over the period that the goods are delivered or the related services are performed, subject to an assessment of recoverability. The Company makes estimates of costs incurred in relation to clinical site costs. The Company analyzes the progress of clinical trials, including levels of patient enrollment, invoices received and contracted costs when evaluating the adequacy of the amount expensed and the related prepaid asset and accrued liability. Significant judgments and estimates must be made and used in determining the accrued balance and expense in any accounting period. The Company reviews and accrues clinical trial study expenses based on work performed and relies upon estimates of those costs applicable to the stage of completion of a study. With respect to clinical site costs, the financial terms of these agreements are subject to negotiation and vary from contract to contract. Payments under these contracts may be uneven, and depend on factors such as the achievement of certain events, the successful recruitment of patients, the completion of portions of the clinical trial or similar conditions. The objective of the Company’s policy is to match the recording of expenses in its financial statements to the actual services received and efforts expended. As such, expense accruals related to clinical site costs are recognized based on the Company’s estimate of the degree of completion of the event or events specified in the specific clinical study or trial contract. Income Taxes Income taxes are accounted for under the asset and liability method. Under this method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to the differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases, operating losses, and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date. Valuation allowances are provided if, based upon the weight of available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. The Company estimates an annual effective tax rate of 0% for the year ending December 31, 2020 and has not recorded an income tax benefit for the nine months ended September 30, 2020 and 2019 since it determined that a full valuation allowance is required against the Company’s deferred tax assets. The Company recognizes the tax benefit from an uncertain tax position only if it is more likely than not to be sustained upon examination based on the technical merits of the position as well as consideration of the available facts and circumstances. When uncertain tax positions exist, the Company recognizes the tax benefit of tax positions to the extent that the benefit will more likely than not be realized. As of September 30, 2020, the Company does not believe any material uncertain tax positions are present. In the event the Company determines that accrual of interest or penalties are necessary in the future, the amount will be presented as a component of income tax expense. Stock-Based Compensation For stock options issued, the Company estimates the grant date fair value of each option using the Black-Scholes option pricing model. The Black-Scholes model takes into account the expected volatility of the Company’s common stock, expected dividends of the Company’s common stock, the risk-free interest rate, the estimated life of the option, the closing market price of the Company’s common stock and the exercise price. The estimates utilized in the Black-Scholes calculation involve inherent uncertainties and the application of management’s judgment. In addition, the Company recognizes expense for equity awards forfeitures as they occur. For restricted stock units (“RSUs”) issued, the Company issues them in the form of Company common stock. The fair value of these awards is based on the market close price per share on the grant date. Prior to January 1, 2020, the Company only granted stock options. Beginning in 2020, for grants to employees, the Company granted a mix of stock options and RSUs. For awards subject to service-based vesting conditions, the Company recognizes stock-based compensation expense on a straight-line basis over the requisite service period, which is generally the vesting term. For awards subject to performance-based vesting conditions, the Company recognizes stock-based compensation expense using the accelerated attribution method when it is probable that the performance condition will be achieved. The expense related to the stock-based compensation is recorded within the same financial statement line item as the grantee’s cash compensation. The Company’s policy upon exercise of stock options and RSUs is that shares will be issued as new shares from the Company’s 2015 Omnibus Incentive Compensation Plan available share pool. Basic and Diluted Net Loss per Common Share Basic net loss per share of common stock is computed by dividing net loss by the weighted average number of shares of common stock outstanding during the period. Diluted net loss per share of common stock includes the effect, if any, from the potential exercise or conversion of securities, such as warrants, stock options, and RSUs, which would result in the issuance of incremental shares of common stock. As the impact of these items is anti-dilutive during periods of net loss, there was no difference between basic and diluted net loss per share of common stock for the three and nine months ended September 30, 2020 and 2019. Recent Accounting Pronouncements In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, ​

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	9 Months Ended
	Sep. 30, 2020
Accrued Expenses and Other Current Liabilities
Accrued Expenses and Other Current Liabilities	Note 3. Accrued Expenses and Other Current Liabilities At September 30, 2020 and December 31, 2019 accrued expenses and other current liabilities consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ ​ 2020 ​ 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ Research and development ​ $ 5,472,963 ​ $ 8,209,594 ​ Accrued compensation ​ ​ 2,522,556 ​ ​ 2,056,356 ​ Other ​ 1,030,893 ​ 683,178 ​ Total ​ $ 9,026,412 ​ $ 10,949,128 ​ ​

Loan and Security Agreement

Loan and Security Agreement	9 Months Ended
	Sep. 30, 2020
Debt Disclosure [Abstract]
Loan and Security Agreement	Note 4. Loan and Security Agreement Silicon Valley Bank Hercules Capital, Inc. a Loan and Security Agreement (the “Loan Agreement”) with Hercules Capital, Inc., in its capacity as administrative agent and collateral agent and as a lender (in such capacity, the “Agent” or “Hercules”) and the other financial institutions that from time to time become parties to the Loan Agreement as lenders (collectively, the “Lenders”). The Loan Agreement provides for term loans in an aggregate principal amount of up to $225.0 million under multiple tranches (the “2020 Term Loan”). The tranches consist of (i) a first tranche consisting of term loans in an aggregate principal amount of $60.0 million, of which $50.0 million was funded to the Company on the Closing Date (the “First Advance”), and of which the remaining $10.0 million is available at the Company’s option at any time through September 15, 2021; (ii) subject to the approval of the Company’s AXS-05 product candidate for the treatment of major depressive disorder (the “First Milestone”), a second tranche consisting of additional term loans in an aggregate principal amount of up to $35.0 million, available at the Company’s option beginning on the date that the First Milestone is achieved through the earlier of (A) 181 days following such date and (B) June 30, 2022; (iii) subject to the approval of the Company’s AXS-07 product candidate for the treatment of migraine (the “Second Milestone”), a third tranche consisting of additional term loans in an aggregate principal amount of up to $20.0 million, available at the Company’s option beginning on the date that the Second Milestone is achieved through the earlier of (A) 181 days following such date and (B) June 30, 2022; (iv) subject to the achievement of either the First Milestone or the Second Milestone and so long as the Company is in compliance with a required ratio of Lender indebtedness to net product revenue, a fourth tranche consisting of additional term loans in an aggregate principal amount of up to $60.0 million, available at the Company’s option beginning on January 1, 2022 and continuing through March 31, 2023; and (v) subject to approval by the Lenders’ in their discretion, a fifth tranche of additional term loans in an aggregate principal amount of up to $50.0 million, available through December 31, 2023. The Company intends to use the proceeds of the Term Loan Advances for working capital and general corporate purposes. In addition, approximately $21.5 million of the proceeds from the First Advance was used to satisfy in full and retire the Company’s indebtedness under the 2019 Term Loan, as amended. The outstanding principal balance of the term loans bears interest at an annual rate equal to the greater of either (i) the prime rate as reported in The Wall Street Journal plus 5.90% or (ii) 9.15% , subject to an ability by the Company, during certain periods (each, a “PIK Deferral Period”), to request a reduction of the then-effective cash-pay interest rate by up to 1.00% per annum (the “Cash Interest Reduction Amount”). Accrued interest is payable monthly following the funding of each term loan. During each PIK Deferral Period, the term loans will bear cash-pay interest, at the reduced amount, and will accrue paid-in-kind interest at a rate equal to the Cash Interest Reduction Amount multiplied by 1.15 , which amount will be capitalized and added to the outstanding principal balance of the term loans on each monthly interest payment date during the PIK Deferral Period. The Company is required to repay the term loans in equal installments of principal and interest commencing on May 1, 2023 through October 1, 2025 (the “Maturity Date”). However, if either the First Milestone or the Second Milestone are achieved prior to May 1, 2023, and no default exists, the amortization commencement date will be automatically extended to November 1, 2023; if both the First Milestone and the Second Milestone are achieved prior to November 1, 2023, and no default exists, the amortization commencement date will be further automatically extended to May 1, 2024 and if any term loans are funded under the fourth tranche noted above prior to May 1, 2024, and no default exists, the amortization commencement date will be further automatically extended to November 1, 2024. On the Maturity Date, all unpaid term loans will be due and payable. As collateral for the obligations, the Company has granted to Hercules a senior security interest in all of Company’s right, title, and interest in, to and under all of Company’s property, inclusive of intellectual property, which includes one of the Company’s existing license agreements (the “License Agreement”) with Antecip Bioventures II LLC (“Antecip”) , subject to limited exceptions . T he Loan Agreement contains customary representations, warranties and covenants, including covenants by the Company limiting additional indebtedness, liens (including a negative pledge on intellectual property and other assets), guaranties, mergers and consolidations, substantial asset sales, investments and loans, certain corporate changes, transactions with affiliates and fundamental changes. At the initial closing, there were no applicable financial covenants contained in the Loan Agreement. Only after additional amounts are drawn down by the Company in the future, if the Company decides to do so, under the terms set forth in the Loan Agreement, there will be certain limited financial covenants that will apply, including: ● E ffective upon the date the outstanding principal amount of the advances under the Loan Agreement equals or exceeds $55.0 million, which has not yet occurred, the Company at all times thereafter must maintain cash in an account or accounts in which Hercules has a first priority security interest, in an aggregate amount greater than or equal to $15.0 million, plus the amount of the Company’s accounts payable under U.S. GAAP not paid after the 180 th day following the invoice for such account payable (such amount, the “Qualified Cash A/P Amount”). ​ ● E ffective upon the later of (i) the last calendar month of the calendar quarter that is twelve months following the earlier of (x) the date that the First Milestone is achieved and (y) the date that the Second Milestone is achieved, or (ii) the date on which the outstanding principal amount of the term loan advances under the Loan Agreement is equal to or greater than $65.0 million, the Company is required to (A) ensure that at all times its market capitalization exceeds $2.0 billion, and that it maintains cash in an account which Hercules has a first priority security interest in an amount not less than 65% of the sum of the outstanding principal amount of the term loan advances plus the Qualified Cash A/P Amount, (B) ensure that at all times that it maintains cash in an account which Hercules has a first priority security interest in an amount not less than 100% of the sum of the outstanding principal amount of the term loan advances plus the Qualified Cash A/P Amount, or (C) achieve at least 60% of the net product revenue solely from the sale of AXS-05 and AXS-07 (which may include royalty, profit sharing, or sales-based milestone revenue recognized in accordance with GAAP, but will not include any upfront or non-sales-based milestone payments under business development or licensing transactions), measured on a trailing six-month basis as of the date of the Company’s most recent quarterly financial statement, determined on a quarterly basis. ​ ● R estrictions on the Company’s ability to incur additional indebtedness, pay dividends, encumber its intellectual property, or engage in certain fundamental business transactions, such as mergers or acquisitions of other businesses, with certain exceptions. The Company’s obligations under the Loan Agreement are subject to acceleration upon the occurrence of specified events of default, including payment default, insolvency and a material adverse change in the Borrower’s business, operations or financial or other condition. In addition, the Company is required to pay a final payment fee equal to the greater of (A) $2,910,000 and (B) 4.85% of the aggregate amount of all term loan advances minus the aggregate amount of repayments made. The final payment fee is being accreted and amortized into interest expense using the effective interest rate method over the term of the loan. The Company may, at its option prepay the term loans in full or in part, subject to a prepayment penalty equal to (i) 2.0% of the principal amount prepaid if the prepayment occurs prior to the first anniversary of the Closing Date, (ii) 1.5% of the principal amount prepaid if the prepayment occurs on or after the first anniversary and prior to the second anniversary of the Closing Date, and (iii) 1.0% of the principal amount prepaid if the prepayment occurs on or after the second anniversary and prior to the third anniversary of the Closing Date. Debt – Modifications and Extinguishments Loan Interest Expense and Amortization The Company incurred interest expense of $421,004 and $1,179,338 for the three and nine months ended September 30, 2020, respectively, as compared to $383,334 and $979,167 for the three and nine months ended September 30, 2019, respectively. In addition, amortization of the final payment fee was $87,425 and $325,453 for the three and nine months ended September 30, 2020, respectively, as compared to $120,322 and $316,246 for the three and nine months ended September 30, 2019, respectively. The outstanding debt and unamortized debt discount balances are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2020 ​ 2019 ​ ​ ​ ​ ​ ​ ​ Total Outstanding Debt ​ $ 50,000,000 ​ $ 20,000,000 Add: accreted liability of final payment fee ​ ​ 7,690 ​ ​ 404,364 Less: unamortized debt discount, long-term ​ ​ (1,981,582) ​ ​ (405,071) Less: current portion of long-term debt ​ ​ — ​ ​ (2,666,667) Loan payable, long-term ​ $ 48,026,108 ​ $ 17,332,626 ​ ​ ​ ​ ​ ​ ​ Current portion of long-term debt ​ $ — ​ $ 2,666,667 Less: current portion of unamortized debt discount ​ ​ — ​ ​ (64,375) Loan payable, current portion ​ $ — ​ $ 2,602,292 ​ In connection with the entry into the Hercules Term Loan, the Company issued to Hercules a warrant to purchase a number of shares of the Company’s common stock equal to 2.5% of the aggregate amount of the Term Loan Advances that are funded. Further information on warrants issued related to this loan and prior debt financings and amendments are disclosed in Note 6 - Stockholders’ Equity under the “Warrants” section. ​ Amortization of the debt discount in relation to warrants issued as described above was $46,920 and $165,556 for the three and nine months ended September 30, 2020, as compared to $56,602 and $155,496 for the three and nine months ended September 30, 2019, respectively. ​ Scheduled Principal Payments on Outstanding Debt, as of September 30, 2020, are as follows: ​ ​ ​ ​ ​ ​ 2020 ​ ​ — ​ 2021 ​ ​ — ​ 2022 ​ ​ — ​ 2023 ​ ​ 12,239,903 ​ 2024 ​ ​ 19,812,629 ​ 2025 ​ ​ 17,947,468 ​ Total principal payments outstanding ​ $ 50,000,000 ​ ​ ​ The Company was in compliance with all covenants and requirements of its financing arrangements as of and during the nine months ended September 30, 2020.

Net Loss per Common Share

Net Loss per Common Share	9 Months Ended
	Sep. 30, 2020
Net Loss per Common Share
Net Loss per Common Share	Note 5. Net Loss per Common Share The following table sets forth the computation of basic and diluted net loss per common share: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended September 30, Nine months ended September 30, ​ 2020 2019 2020 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic and diluted net loss per common share: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net loss ​ $ (22,924,815) ​ $ (19,135,612) ​ $ (73,735,953) ​ $ (43,538,202) Weighted average common shares outstanding—basic and diluted ​ 37,311,726 ​ 34,445,489 ​ 37,158,513 ​ 33,771,671 Net loss per common share—basic and diluted ​ $ (0.61) ​ $ (0.56) ​ $ (1.98) ​ $ (1.29) ​ The following potentially dilutive securities outstanding at September 30, 2020 and 2019 have been excluded from the computation of diluted weighted average shares outstanding, as they would be anti-dilutive: ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ 2020 2019 ​ ​ ​ ​ ​ Stock options 3,909,855 3,184,842 ​ Restricted stock units ​ 155,922 ​ — ​ Warrants 15,541 110,603 ​ Total 4,081,318 3,295,445 ​ ​

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2020
Stockholders' Equity
Stockholders' Equity	Note 6. Stockholders’ Equity Capital Structure In May 2019, the Company entered into a Sales Agreement with SVB Leerink (the “May 2019 Sales Agreement”), pursuant to which the Company could sell up to $50 million in shares of its common stock from time to time through SVB Leerink, acting as the Company’s sales agent, in one or more at-the-market offerings utilizing the 2016 Shelf Registration Statement (as defined below). SVB Leerink was entitled to receive a commission of 3.0% of the gross proceeds for any shares sold under the May 2019 Sales Agreement. The shares that were unsold under the May 2019 Sales Agreement at the time of the expiration of the 2016 Shelf Registration Statement were rolled over to the December 2019 Sales Agreement (see below). In December 2019, the Company entered into a new Sales Agreement with SVB Leerink (the “December 2019 Sales Agreement”), pursuant to which the Company may sell up to $80 million in shares of the Company’s common stock from time to time through SVB Leerink, acting as the Company’s sales agent, in one or more at-the-market offerings utilizing the 2019 Shelf Registration Statement. SVB Leerink is entitled to receive a commission of 3.0% of the gross proceeds for any shares sold under the December 2019 Sales Agreement. The Company received approximately $12.4 million in gross proceeds through the sale of 141,678 shares, of which net proceeds were approximately $12.1 million during the nine months ended September 30, 2020. In December 2019, the Company completed an underwritten public offering, whereby the Company sold 2,300,000 shares of common stock at a public offering price of $87.00 per share. The Company received gross proceeds of approximately $200.1 million and net proceeds of approximately $187.1 million, after deducting underwriting discounts and offering expenses. The holders of shares of common stock are entitled to one vote for each share of common stock held at all meetings of stockholders and written actions in lieu of meetings. The holders of shares of common stock are entitled to receive dividends, if and when declared by the board of directors. Shelf Registration Statement On December 5, 2019, the Company filed an automatic shelf registration statement (“2019 Shelf Registration Statement”) with the Securities and Exchange Commission (“SEC”) for the issuance of common stock, preferred stock, warrants, rights, debt securities and units. The 2019 Shelf Registration Statement was automatically effective upon filing with the SEC and is currently the Company’s only active shelf registration statement. The 2019 Shelf Registration Statement was filed in part to replace the Company’s previous non-automatic shelf registration statement, which became effective on December 16, 2016, and provided for the issuance of common stock, preferred stock, warrants, rights, debt securities and units up to an aggregate amount of $150.0 million (the “2016 Shelf Registration Statement”). The 2016 Shelf Registration Statement expired on December 16, 2019. Through the date of this report, the Company has issued common stock of approximately $219.8 million pursuant to the 2019 Shelf Registration Statement. ​ Equity Incentive Plans ​ There were 4,134,138 shares available for the issuance of stock options or stock-based awards under the Company’s 2015 Omnibus Incentive Compensation Plan at September 30, 2020. Stock Options The following table sets forth the stock option activity for the nine months ended September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ Weighted ​ average ​ Aggregate ​ ​ Number ​ average ​ contractual ​ intrinsic ​ ​ of shares ​ exercise price ​ term ​ value Outstanding at December 31, 2019 3,458,447 ​ $ 10.19 ​ ​ ​ ​ ​ Granted ​ 642,509 ​ ​ 54.27 ​ ​ ​ ​ ​ ​ Exercised ​ (123,456) ​ ​ 8.18 ​ ​ ​ ​ ​ ​ Forfeited ​ (67,645) ​ ​ 41.57 ​ ​ ​ ​ ​ ​ Expired ​ — ​ ​ — ​ ​ ​ ​ ​ ​ Outstanding at September 30, 2020 3,909,855 ​ $ 16.95 7.5 ​ $ 213,789,330 ​ Vested and expected to vest at September 30, 2020 3,903,686 ​ $ 16.98 7.5 ​ $ 213,357,801 ​ Exercisable at September 30, 2020 2,319,685 ​ $ 9.99 6.2 ​ $ 142,292,294 ​ ​ The fair value of each stock option grant is estimated on the date of grant using the Black-Scholes option pricing model. The expected term of the Company’s stock options has been determined utilizing the “simplified” method as described in the SEC’s Staff Accounting Bulletin No. 107 relating to stock-based compensation. The simplified method was chosen because the Company has limited historical option exercise experience due to its short operating history. The risk-free interest rate is based on the U.S. Treasury yield in effect at the time of grant for a period approximately equal to the expected term of the award. Expected dividend yield is based on the fact that the Company has never paid cash dividends and does not expect to pay any cash dividends in the foreseeable future. Expected volatility is based on historical volatilities of similar entities within the Company’s industry which were commensurate with the Company’s expected term assumption. The weighted average grant date fair value of options granted was $34.73 per option for the nine months ended September 30, 2020. As of September 30, 2020, there was $26.9 million of total unrecognized compensation cost related to non-vested stock options which is expected to be recognized over a weighted average period of 3.0 years. These amounts do not include 11,222 options outstanding as of September 30, 2020, which are performance-based and vest upon the achievement of certain corporate milestones. Stock‑based compensation will be measured and recorded if and when it is probable that the milestone will occur. Restricted Stock Units ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ average ​ ​ ​ Number ​ grant date ​ ​ ​ of shares ​ fair value ​ Outstanding at December 31, 2019 — ​ $ — Granted ​ 156,378 ​ ​ 34.67 ​ Released ​ — ​ ​ — ​ Forfeited ​ (456) ​ ​ 45.14 ​ Outstanding at September 30, 2020 155,922 ​ $ 34.64 ​ Stock-based compensation expense recognized for the three and nine months ended September 30, 2020 and 2019 was allocated as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended September 30, ​ Nine months ended September 30, ​ ​ 2020 ​ 2019 ​ 2020 ​ 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Research and development ​ $ 860,744 ​ $ 286,234 ​ $ 2,532,649 ​ $ 652,666 ​ General and administrative ​ 2,008,074 ​ 870,201 ​ 6,617,724 ​ 2,648,635 ​ Total ​ $ 2,868,818 ​ $ 1,156,435 ​ $ 9,150,373 ​ $ 3,301,301 ​ ​ ​ Warrants The following table summarizes warrant activity for the nine months ended September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ average ​ ​ Warrants ​ exercise price Outstanding at December 31, 2019 69,656 ​ $ 7.21 Issued ​ 15,541 ​ ​ 80.43 Exercised ​ (69,656) ​ ​ 7.21 Outstanding at September 30, 2020 15,541 ​ $ 80.43 ​ Outstanding Warrants ​ In connection with the first advance of the 2020 Term Loan, Hercules Capital Inc. received warrants to purchase an aggregate 15,541 shares of the Company’s common stock at an exercise price of $80.43 per share, which was the volume weighted average price of the Company’s common stock over the ten -day trading period immediately preceding the initial closing, subject to certain limited adjustments as specified in the warrant. The warrants are exercisable for seven years from the date of issuance. The warrants were classified as a component of stockholders’ equity. T he relative fair value of the warrants of approximately $0.9 million at the time of issuance, which was determined using the Black-Scholes option-pricing model, was recorded as additional paid-in capital and reduced the carrying value of the debt. The discount on the debt is being amortized to interest expense over the term of the debt utilizing the effective interest rate method. ​ Fully Exercised Warrants ​ In connection with the 2016 Original Term Loan, SVB and Life Science Loans, LLC (“Life Science”) received warrants to purchase an aggregate of 65,228 shares of the Company’s common stock at an exercise price of $7.41 per share, which were exercisable for seven years from the date of issuance. The warrants were classified as a component of stockholders’ equity. In September 2019, SVB exercised in full the 32,614 warrants it received in connection with the 2016 Original Term Loan via a cashless exercise. The Company issued SVB 24,328 shares of its common stock in connection with the warrant exercise, and did not receive any cash proceeds. In addition, in May 2020, Life Science exercised in full the 32,614 warrants it received in connection with the 2016 Original Term Loan via a cashless exercise. The Company issued Life Science 29,982 shares of its common stock in connection with the warrant exercise and did not receive any cash proceeds. As of September 30, 2020, none of the warrants issued in connection with the 2016 Original Term Loan were outstanding. ​ Additionally, in connection with the 2016 Amended Term Loan, SVB and WestRiver received warrants to purchase an aggregate 15,750 shares of the Company’s common stock at an exercise price of $3.06 per share, which were exercisable for seven years from the date of issuance. Both warrants issued in connection with the 2016 Original Term Loan and the 2016 Amended Term Loan were classified as a component of stockholders’ equity. Prior to entering into the 2019 Term Loan, the fair value of these warrants and the closing costs were recorded as debt discounts and were being amortized using the effective interest rate method over the term of the loan. In August 2019, SVB exercised in full the 7,875 warrants it received in connection with the 2016 Amended Term Loan via a cashless exercise. The Company issued SVB 6,969 shares of its common stock in connection with the warrant exercise, and did not receive any cash proceeds. In August 2020, WestRiver exercised in full the 7,875 warrants it received in connection with the 2016 Amended Term Loan via a cashless exercise. The Company issued SVB 7,579 shares of its common stock in connection with the warrant exercise, and did not receive any cash proceeds. As of September 30, 2020, none of the warrants issued in connection with the 2016 Amended Term Loan were outstanding. ​ Due to the debt modification upon entry of the 2019 Term Loan, the unamortized balance of the deferred debt issuance costs incurred with the 2016 Amended Term Loan continued to be amortized through maturity in February 2023 along with the debt issuance costs of the 2019 Term Loan utilizing the effective interest rate method. ​ In connection with the 2019 Term Loan, SVB and WestRiver received warrants to purchase an aggregate of 70,000 shares of the Company’s common stock at a price per share equal to $8.10 (the “March 2019 Warrants”). The warrants would initially be earned based upon the usage of the facility and are exercisable until March 4, 2026. The warrants were classified as a component of stockholder’s equity, of which 58,332 warrants were immediately exercisable and the remaining 11,668 warrants could be earned based on usage of the second tranche of the 2019 Term Loan. The additional warrants were initially immediately exercisable if and when the Term B Loan Advance was funded (however, the March 2019 Warrants were amended in connection with the First Amendment to the 2019 Term Loan, as discussed below). T he relative fair value of the warrants of approximately $0.4 million at the time of issuance, which was determined using the Black-Scholes option-pricing model, was recorded as additional paid-in capital and reduced the carrying value of the debt. The discount on the debt is being amortized to interest expense over the term of the debt utilizing the effective interest rate method. ​ In connection with the First Amendment to the 2019 Term Loan, the March 2019 Warrants were amended to fix the number of shares that may be issued upon exercise of each such March 2019 Warrant at 29,167 shares of common stock, and SVB and WestRiver were issued new warrants (the “July 2019 Warrants”), which were to become exercisable only upon funding of the Term B Loan Advance, to purchase 5,750 shares of the Company’s common stock at a price per share equal to $25.71. The July 2019 Warrants replaced the portion of the March 2019 Warrants that could originally be earned by SVB and WestRiver upon funding of the Term B Loan Advance. Because the Company did not draw down on the Term B Loan Advance by December 31, 2019, the July 2019 Warrants have been terminated. In December 2019, SVB exercised in full its portion of 29,167 warrants it received in connection with the 2019 Term Loan via a cashless exercise. The Company issued SVB 24,185 shares of its common stock in connection with the warrant exercise and did not receive any cash proceeds. In August 2020, WestRiver exercised in full its portion of 29,167 warrants it received in connection with the 2019 Term Loan via a cashless exercise. The Company issued SVB 26,270 shares of its common stock in connection with the warrant exercise and did not receive any cash proceeds. As of September 30, 2020, none of the warrants issued in connection with the First Amendment to the 2019 Term Loan were outstanding. ​ In relation to the retirement of the 2019 Term Loan, the unamortized portion of the debt issuance costs from the issuance of these warrants were fully extinguished and are included in the $1.2 million loss on extinguishment of debt on the statement of operations.

License Agreements

License Agreements	9 Months Ended
	Sep. 30, 2020
License Agreements.
License Agreements	Note 7. License Agreements ​ Exclusive License Agreement with Pfizer ​ In January 2020, the Company entered into an exclusive license agreement with Pfizer Inc. (“Pfizer”) for Pfizer’s clinical and nonclinical data, and intellectual property for reboxetine, the active pharmaceutical ingredient in AXS-12 which the Company is developing for the treatment of narcolepsy. The agreement also provides the Company exclusive rights to develop and commercialize esreboxetine, a new late-stage product candidate now referred to as AXS-14, in the U.S. for the treatment of fibromyalgia. ​ Under the terms of the agreement, Pfizer received 82,019 shares of the Company’s common stock having a stated value of $8.0 million, based on the average closing price of the Company’s common stock for the ten prior trading days of $97.54 , in consideration for the license and rights and also received an upfront cash payment of $3.0 million. The Company determined that the fair value of each share of common stock granted to Pfizer on the closing date of January 9, 2020 was $87.24 , based on the closing price of the Company’s stock on that date. As a result, the fair value of the stock issued was $7.2 million and therefore, the total research and development expense recognized was $10.2 million related to the Pfizer license agreement during the nine months ended September 30, 2020. ​ Pfizer can also receive up to $323 million in regulatory and sales milestones, and tiered mid-single to low double-digit royalties on future sales. Pfizer will also have a right of first negotiation on any potential future strategic transactions involving AXS-12 and AXS-14. During the nine months ended September 30, 2020, no milestone payments or royalties were paid to Pfizer by the Company. ​ Exclusive License Agreements with Antecip ​ In 2012, the Company entered into three exclusive license agreements with Antecip, in which it was granted exclusive licenses to develop, manufacture, and commercialize Antecip’s patents and applications related to the development of AXS-02, AXS-05, and AXS-04, a product candidate that is currently in early stage development, anywhere in the world for human therapeutic, veterinary, and diagnostic use. Pursuant to the agreements, the Company is required to use commercially reasonable efforts to develop, obtain regulatory approval for and commercialize AXS-02, AXS-05, and AXS-04. Under the terms of the agreements, the Company is required to pay to Antecip a royalty equal to 4.5% for AXS-02, 3.0% for AXS-05, and 1.5% for AXS-04, of net sales of products containing the licensed technology by the Company, its affiliates, or permitted sublicensees. These royalty payments are subject to reduction by an amount up to 50.0% of any required payments to third parties. Unless earlier terminated by a party for cause or by the Company for convenience, the agreements shall remain in effect on a product-by-product and country-by-country basis until the later to occur of (i) the applicable product is no longer covered by a valid claim in that country or (ii) 10 years from the first commercial sale of the applicable product in that country. Upon expiration of the agreements with respect to a product in a country, the Company’s license grant for that product in that country will become a fully paid-up, royalty-free, perpetual non-exclusive license. If Antecip terminates any of the agreements for cause, or if the Company exercises its right to terminate any of the agreements for convenience, the rights granted to the Company under such terminated agreement will revert to Antecip. To date, the Company has not been required to make any payments to Antecip under any of the license agreements. ​ In connection with the 2020 Term Loan, the Company entered into a Direct Agreement with Antecip pursuant to which Antecip consented to the collateral assignment of the License Agreement to Hercules, among other things. ​ ​

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2020
Summary of Significant Accounting Policies
Significant Risks and Uncertainties	Significant Risks and Uncertainties The Company’s operations are subject to a number of factors that can affect its operating results and financial condition. Such factors include, but are not limited to: the results of clinical testing and trial activities of the Company’s product candidates; the Company’s ability to obtain regulatory approval to market its products, if approved; competition from products manufactured and sold or being developed by other companies; the price of, and demand for, the Company’s products, if approved; the Company’s ability to negotiate favorable licensing or other manufacturing and marketing agreements for its products, if approved; and the Company’s ability to raise additional financing. If the Company does not successfully commercialize any of its product candidates, it will be unable to generate recurring product revenue or achieve and maintain profitability.
Use of Estimates	Use of Estimates Management considers many factors in developing the estimates and assumptions that are used in the preparation of these financial statements. Management must apply significant judgment in this process. In addition, other factors may affect estimates, including expected business and operational changes, sensitivity and volatility associated with the assumptions used in developing estimates, and whether historical trends are expected to be representative of future trends. The estimation process often may yield a range of potentially reasonable estimates of the ultimate future outcomes and management must select an amount that falls within that range of reasonable estimates. This process may result in actual results differing materially from those estimated amounts used in the preparation of the financial statements if these results differ from historical experience, or other assumptions do not turn out to be substantially accurate, even if such assumptions are reasonable when made. In preparing these financial statements, management used significant estimates in the following areas, among others: stock-based compensation expense; the determination of the fair value of the warrants; the accounting for research and development costs; and the recoverability of the Company’s net deferred tax assets and related valuation allowance.
Foreign Currency Translation	Foreign Currency Translation Expenses denominated in foreign currency are translated into U.S. dollars at the exchange rate on the date the expense is incurred. Assets and liabilities of foreign operations are translated at period-end exchange rates. The effect of exchange rate fluctuations on translating foreign currency into U.S. dollars is included in the Statements of Operations and is not material to the Company’s financial statements.
Segment and Geographic Information	Segment and Geographic Information Operating segments are defined as components of an enterprise for which separate discrete information is available for evaluation by the chief operating decision maker or decision-making group, in deciding how to allocate resources and in assessing performance. The Company views its operations and manages its business as one operating segment, which is the business of developing novel therapies for the management of CNS disorders.
Cash Equivalents	Cash Equivalents The Company considers all highly liquid investments that have maturities of three months or less when acquired to be cash equivalents. The Company’s cash and cash equivalents includes holdings in checking and overnight sweep accounts. The Company’s cash equivalents, which are money market funds held in a sweep account, are measured at fair value on a recurring basis. As of September 30, 2020, the balance of cash and cash equivalents was $202.4 million, which approximates fair value and was determined based upon Level 1 inputs. The sweep account is valued using quoted market prices with no valuation adjustments applied. Accordingly, these securities are categorized as Level 1.
Concentration of Credit Risk	Concentration of Credit Risk
Fair Value of Financial Instruments	Fair Value of Financial Instruments 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 at the measurement date. Assets and liabilities that are measured at fair value are reported using a three-level fair value hierarchy that prioritizes the inputs used to measure fair value. This hierarchy maximizes the use of observable inputs and minimizes the use of unobservable inputs. The three levels of inputs used to measure fair value are as follows: Level 1 Level 2 Level 3 To the extent that valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement.
Debt Issuance Costs	Debt Issuance Costs Debt issuance costs consist of costs incurred in obtaining long-term financing. These costs are classified on the consolidated balance sheet as a direct deduction from the carrying amount of the related debt liability. These expenses are deferred and amortized as part of interest expense in the consolidated statement of operations using the effective interest rate method over the term of the debt agreement.
Equipment	Equipment Equipment consists primarily of computer equipment and is recorded at cost. Equipment is depreciated on a straight-line basis over its estimated useful life, which the Company estimates to be three years . When equipment is sold or otherwise disposed of, the cost and related accumulated depreciation are removed from the accounts and the resulting gain or loss is included in operating expenses.
Research and Development Costs	Research and Development Costs Research and development expenses primarily consist of costs incurred in performing research and development activities, including preclinical studies, clinical trials, manufacturing costs, regulatory costs, employee salaries and benefits, stock-based compensation expense, contract services, including external research and development expenses incurred under arrangements with third parties, such as contract research organizations (“CROs”), facilities costs, overhead costs, depreciation, and other related costs. Generally, research and development costs are expensed as incurred. Nonrefundable advance payments for goods or services that will be used or rendered for future research and development activities are deferred and amortized over the period that the goods are delivered or the related services are performed, subject to an assessment of recoverability. The Company makes estimates of costs incurred in relation to clinical site costs. The Company analyzes the progress of clinical trials, including levels of patient enrollment, invoices received and contracted costs when evaluating the adequacy of the amount expensed and the related prepaid asset and accrued liability. Significant judgments and estimates must be made and used in determining the accrued balance and expense in any accounting period. The Company reviews and accrues clinical trial study expenses based on work performed and relies upon estimates of those costs applicable to the stage of completion of a study. With respect to clinical site costs, the financial terms of these agreements are subject to negotiation and vary from contract to contract. Payments under these contracts may be uneven, and depend on factors such as the achievement of certain events, the successful recruitment of patients, the completion of portions of the clinical trial or similar conditions. The objective of the Company’s policy is to match the recording of expenses in its financial statements to the actual services received and efforts expended. As such, expense accruals related to clinical site costs are recognized based on the Company’s estimate of the degree of completion of the event or events specified in the specific clinical study or trial contract.
Income Taxes	Income Taxes Income taxes are accounted for under the asset and liability method. Under this method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to the differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases, operating losses, and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date. Valuation allowances are provided if, based upon the weight of available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. The Company estimates an annual effective tax rate of 0% for the year ending December 31, 2020 and has not recorded an income tax benefit for the nine months ended September 30, 2020 and 2019 since it determined that a full valuation allowance is required against the Company’s deferred tax assets. The Company recognizes the tax benefit from an uncertain tax position only if it is more likely than not to be sustained upon examination based on the technical merits of the position as well as consideration of the available facts and circumstances. When uncertain tax positions exist, the Company recognizes the tax benefit of tax positions to the extent that the benefit will more likely than not be realized. As of September 30, 2020, the Company does not believe any material uncertain tax positions are present. In the event the Company determines that accrual of interest or penalties are necessary in the future, the amount will be presented as a component of income tax expense.
Stock Based Compensation	Stock-Based Compensation For stock options issued, the Company estimates the grant date fair value of each option using the Black-Scholes option pricing model. The Black-Scholes model takes into account the expected volatility of the Company’s common stock, expected dividends of the Company’s common stock, the risk-free interest rate, the estimated life of the option, the closing market price of the Company’s common stock and the exercise price. The estimates utilized in the Black-Scholes calculation involve inherent uncertainties and the application of management’s judgment. In addition, the Company recognizes expense for equity awards forfeitures as they occur. For restricted stock units (“RSUs”) issued, the Company issues them in the form of Company common stock. The fair value of these awards is based on the market close price per share on the grant date. Prior to January 1, 2020, the Company only granted stock options. Beginning in 2020, for grants to employees, the Company granted a mix of stock options and RSUs. For awards subject to service-based vesting conditions, the Company recognizes stock-based compensation expense on a straight-line basis over the requisite service period, which is generally the vesting term. For awards subject to performance-based vesting conditions, the Company recognizes stock-based compensation expense using the accelerated attribution method when it is probable that the performance condition will be achieved. The expense related to the stock-based compensation is recorded within the same financial statement line item as the grantee’s cash compensation. The Company’s policy upon exercise of stock options and RSUs is that shares will be issued as new shares from the Company’s 2015 Omnibus Incentive Compensation Plan available share pool.
Basic and Diluted Net Loss per Common Share	Basic and Diluted Net Loss per Common Share Basic net loss per share of common stock is computed by dividing net loss by the weighted average number of shares of common stock outstanding during the period. Diluted net loss per share of common stock includes the effect, if any, from the potential exercise or conversion of securities, such as warrants, stock options, and RSUs, which would result in the issuance of incremental shares of common stock. As the impact of these items is anti-dilutive during periods of net loss, there was no difference between basic and diluted net loss per share of common stock for the three and nine months ended September 30, 2020 and 2019.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes,

Accrued Expenses and Other Cu_2

Accrued Expenses and Other Current Liabilities (Tables)	9 Months Ended
	Sep. 30, 2020
Accrued Expenses
Schedule of accrued expenses	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ ​ 2020 ​ 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ Research and development ​ $ 5,472,963 ​ $ 8,209,594 ​ Accrued compensation ​ ​ 2,522,556 ​ ​ 2,056,356 ​ Other ​ 1,030,893 ​ 683,178 ​ Total ​ $ 9,026,412 ​ $ 10,949,128 ​

Loan and Security Agreement (Ta

Loan and Security Agreement (Tables)	9 Months Ended
	Sep. 30, 2020
Debt Disclosure [Abstract]
Schedule of outstanding debt and unamortized debt discount balances	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2020 ​ 2019 ​ ​ ​ ​ ​ ​ ​ Total Outstanding Debt ​ $ 50,000,000 ​ $ 20,000,000 Add: accreted liability of final payment fee ​ ​ 7,690 ​ ​ 404,364 Less: unamortized debt discount, long-term ​ ​ (1,981,582) ​ ​ (405,071) Less: current portion of long-term debt ​ ​ — ​ ​ (2,666,667) Loan payable, long-term ​ $ 48,026,108 ​ $ 17,332,626 ​ ​ ​ ​ ​ ​ ​ Current portion of long-term debt ​ $ — ​ $ 2,666,667 Less: current portion of unamortized debt discount ​ ​ — ​ ​ (64,375) Loan payable, current portion ​ $ — ​ $ 2,602,292
Schedule of principal payments	​ ​ ​ ​ ​ ​ 2020 ​ ​ — ​ 2021 ​ ​ — ​ 2022 ​ ​ — ​ 2023 ​ ​ 12,239,903 ​ 2024 ​ ​ 19,812,629 ​ 2025 ​ ​ 17,947,468 ​ Total principal payments outstanding ​ $ 50,000,000 ​

Net Loss per Common Share (Tabl

Net Loss per Common Share (Tables)	9 Months Ended
	Sep. 30, 2020
Net Loss per Common Share
Computation of basic and diluted net loss per common share	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended September 30, Nine months ended September 30, ​ 2020 2019 2020 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic and diluted net loss per common share: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net loss ​ $ (22,924,815) ​ $ (19,135,612) ​ $ (73,735,953) ​ $ (43,538,202) Weighted average common shares outstanding—basic and diluted ​ 37,311,726 ​ 34,445,489 ​ 37,158,513 ​ 33,771,671 Net loss per common share—basic and diluted ​ $ (0.61) ​ $ (0.56) ​ $ (1.98) ​ $ (1.29)
Schedule of potentially dilutive securities	​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ 2020 2019 ​ ​ ​ ​ ​ Stock options 3,909,855 3,184,842 ​ Restricted stock units ​ 155,922 ​ — ​ Warrants 15,541 110,603 ​ Total 4,081,318 3,295,445 ​

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	9 Months Ended
	Sep. 30, 2020
Stockholders' Equity
Schedule of stock option activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ Weighted ​ average ​ Aggregate ​ ​ Number ​ average ​ contractual ​ intrinsic ​ ​ of shares ​ exercise price ​ term ​ value Outstanding at December 31, 2019 3,458,447 ​ $ 10.19 ​ ​ ​ ​ ​ Granted ​ 642,509 ​ ​ 54.27 ​ ​ ​ ​ ​ ​ Exercised ​ (123,456) ​ ​ 8.18 ​ ​ ​ ​ ​ ​ Forfeited ​ (67,645) ​ ​ 41.57 ​ ​ ​ ​ ​ ​ Expired ​ — ​ ​ — ​ ​ ​ ​ ​ ​ Outstanding at September 30, 2020 3,909,855 ​ $ 16.95 7.5 ​ $ 213,789,330 ​ Vested and expected to vest at September 30, 2020 3,903,686 ​ $ 16.98 7.5 ​ $ 213,357,801 ​ Exercisable at September 30, 2020 2,319,685 ​ $ 9.99 6.2 ​ $ 142,292,294 ​
Schedule of RSU activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ average ​ ​ ​ Number ​ grant date ​ ​ ​ of shares ​ fair value ​ Outstanding at December 31, 2019 — ​ $ — Granted ​ 156,378 ​ ​ 34.67 ​ Released ​ — ​ ​ — ​ Forfeited ​ (456) ​ ​ 45.14 ​ Outstanding at September 30, 2020 155,922 ​ $ 34.64
Schedule of stock-based compensation expense	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended September 30, ​ Nine months ended September 30, ​ ​ 2020 ​ 2019 ​ 2020 ​ 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Research and development ​ $ 860,744 ​ $ 286,234 ​ $ 2,532,649 ​ $ 652,666 ​ General and administrative ​ 2,008,074 ​ 870,201 ​ 6,617,724 ​ 2,648,635 ​ Total ​ $ 2,868,818 ​ $ 1,156,435 ​ $ 9,150,373 ​ $ 3,301,301 ​
Schedule of warrant activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ average ​ ​ Warrants ​ exercise price Outstanding at December 31, 2019 69,656 ​ $ 7.21 Issued ​ 15,541 ​ ​ 80.43 Exercised ​ (69,656) ​ ​ 7.21 Outstanding at September 30, 2020 15,541 ​ $ 80.43

Nature of Business and Basis _2

Nature of Business and Basis of Presentation (Details)	Sep. 30, 2020USD ($)product$ / sharesshares	Dec. 31, 2019USD ($)$ / sharesshares
Nature of Business and Basis of Presentation
Number of late-stage candidates in Company's product candidate portfolio | product	5
Common stock, shares authorized | shares	150,000,000	150,000,000
Common stock, par value | $ / shares	$ 0.0001	$ 0.0001
Preferred stock, shares authorized | shares	10,000,000	10,000,000
Preferred stock, par value | $ / shares	$ 0.0001	$ 0.0001
Accumulated deficit | $	$ 249,631,446	$ 175,895,493

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Details)	9 Months Ended
	Sep. 30, 2020USD ($)Institutionsegment	Dec. 31, 2019USD ($)
Segment and Geographic Information
Number of operating segments | segment	1
Cash Equivalents
Cash Equivalents | $	$ 202,360,292	$ 219,966,167
Concentration of Credit Risk
Number of financial institutions that hold the Company's cash | Institution	1
Equipment
Estimated useful life	3 years
Income Taxes
Effective tax rate	0.00%

Accrued Expenses and Other Cu_3

Accrued Expenses and Other Current Liabilities (Details) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Accrued Expenses and Other Current Liabilities
Research and development	$ 5,472,963	$ 8,209,594
Accrued compensation	2,522,556	2,056,356
Other	1,030,893	683,178
Total	$ 9,026,412	$ 10,949,128

Loan and Security Agreement - A

Loan and Security Agreement - Additional Information (Details)	1 Months Ended			3 Months Ended		9 Months Ended
	Sep. 30, 2020USD ($)	Mar. 31, 2019USD ($)	Nov. 30, 2016USD ($)tranche	Sep. 30, 2020USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2019USD ($)
Repayment of principal on term loan						$ 21,660,000	$ 7,238,889
Loss on extinguishment of debt				$ (1,247,012)		(1,247,012)
Interest expense				421,004	$ 383,334	1,179,338
Amortization of debt issuance costs				$ 87,425	$ 120,322		316,246
Term Loan
Interest expense							$ 979,167
Amortization of debt issuance costs						$ 325,453
Term Loan 2020
First advance used to repay previous debt	$ 21,500,000
Cash pay interest rate	1.00%
Cash pay interest multiplier	1.15			1.15		1.15
Percentage of final payment fee	4.85%
Final payment fee	$ 2,910,000
Base interest rate	9.15%			9.15%		9.15%
Loss on extinguishment of debt						$ 1,200,000
Term Loan 2020 | Prepayment Occurs Prior to First Anniversary of Closing Date
Maximum loan amount	$ 225,000,000			$ 225,000,000		225,000,000
Percentage of prepayment penalty	2.00%
Term Loan 2020 | Prepayment Occurs on or After First Anniversary and Prior to Second Anniversary of the Closing Date
Percentage of prepayment penalty	1.50%
Term Loan 2020 | Prepayment Occurs on or After Second Anniversary and Prior to Third Anniversary of Closing Date
Percentage of prepayment penalty	1.00%
Term Loan 2020 | Outstanding principle and advances under the loans agreement exceeds 55 million
Minimum cash to be maintain as a first priority security interest	$ 15,000,000			15,000,000		15,000,000
Period of unpaid invoices amount maintain as security	180 days
Term Loan 2020 | Outstanding principle and advances under the loans agreement exceeds 65 million
Minimum amount of market capital to be maintained	$ 2,000,000,000
Minimum percentage of cash to be maintained as a security following market capitalization condition	65.00%
Minimum percentage of cash to be maintained as a security	100.00%
Term Loan 2020 | Outstanding principle and advances under the loans agreement exceeds 65 million | AXS-05 and AXS-07
Minimum product revenue percent	60.00%
Term Loan 2020 | Prime Rate
Interest rate basis	5.90%
Term loan 2020 tranche one
Maximum loan amount	$ 60,000,000			60,000,000		60,000,000
Proceeds from debt	50,000,000
Remaining credit facility to be drawn	10,000,000			10,000,000		10,000,000
Term loan 2020 tranche two
Maximum loan amount	$ 35,000,000			35,000,000		35,000,000
Period to achieve first milestone	181 days
Term loan 2020 tranche three
Maximum loan amount	$ 20,000,000			20,000,000		20,000,000
Period to achieve second milestone	181 days
Term loan 2020 tranche four
Maximum loan amount	$ 60,000,000			60,000,000		60,000,000
Term loan 2020 tranche five
Maximum loan amount	50,000,000			50,000,000		50,000,000
2019 Term Loan
Maximum loan amount		$ 24,000,000
Interest rate basis		7.50%
Repayment of principal on term loan		$ 1,260,000
Loss on extinguishment of debt						(1,200,000)
Term Loan 2019, Tranche One
Loan amount		20,000,000
Final payment fee		850,000
Repayment of principal on term loan		5,600,000
Term Loan 2019, Tranche Two
Remaining credit facility to be drawn		$ 4,000,000
Original Term Loan 2016
Maximum loan amount			$ 20,000,000
Number of loan tranches | tranche			3
Term Loan 2016, Tranche One
Maximum loan amount			$ 10,000,000
Term Loan 2016, Tranche Two and Three
Maximum loan amount			10,000,000
Amended Term Loan 2016
Remaining credit facility to be drawn			$ 4,000,000
Minimum | Term Loan 2020 | Outstanding principle and advances under the loans agreement exceeds 55 million
Outstanding amount	55,000,000			55,000,000		55,000,000
Minimum | Term Loan 2020 | Outstanding principle and advances under the loans agreement exceeds 65 million
Outstanding amount	$ 65,000,000			$ 65,000,000		$ 65,000,000
Warrants
Percentage of aggregate amount of loan						2.50%

Loan and Security Agreement - O

Loan and Security Agreement - Outstanding Debt and Unamortized Debt Discount (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Total Outstanding Debt	$ 50,000,000		$ 50,000,000		$ 20,000,000
Add: accreted liability of final payment fee	7,690		7,690		404,364
Less: unamortized debt discount, long-term	(1,981,582)		(1,981,582)		(405,071)
Less: current portion of long-term debt					(2,666,667)
Loan payable, long-term	48,026,108		48,026,108		17,332,626
Current portion of long-term debt					2,666,667
Current portion of unamortized debt discount					(64,375)
Loan payable, current portion					$ 2,602,292
Amortization of debt discount			491,009	$ 471,742
Warrants
Amortization of debt discount	$ 46,920	$ 56,602	$ 165,556	$ 155,496

Loan and Security Agreement - S

Loan and Security Agreement - Schedule of Principal Payments (Details) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Debt Disclosure [Abstract]
2023	$ 12,239,903
2024	19,812,629
2025	17,947,468
Total principal payments outstanding	$ 50,000,000	$ 20,000,000

Net Loss per Common Share - Com

Net Loss per Common Share - Computation of Basic and Diluted Net Loss per Common Share (Details) - USD ($)	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Basic and diluted net loss per common share:
Net loss	$ (22,924,815)	$ (18,326,992)	$ (32,484,146)	$ (19,135,612)	$ (13,762,214)	$ (10,640,376)	$ (73,735,953)	$ (43,538,202)
Weighted average common shares outstanding, basic and diluted	37,311,726			34,445,489			37,158,513	33,771,671
Net loss per common share, basic and diluted	$ (0.61)			$ (0.56)			$ (1.98)	$ (1.29)

Net Loss per Common Share - Pot

Net Loss per Common Share - Potentially Dilutive Securities Outstanding (Details) - shares	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities	4,081,318	3,295,445
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities	3,909,855	3,184,842
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities	155,922
Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities	15,541	110,603

Stockholders' Equity - Capital

Stockholders' Equity - Capital Structure (Details) $ / shares in Units, $ in Millions	1 Months Ended		9 Months Ended
	Dec. 31, 2019USD ($)$ / sharesshares	May 31, 2019USD ($)	Sep. 30, 2020USD ($)Vote / sharesshares	Dec. 16, 2016USD ($)
Subsidiary, Sale of Stock [Line Items]
Common stock sales agreement, authorized amount	$ 80	$ 50
Common stock sales agreement, gross sales			$ 12.4
Common stock sales agreement, net sales			$ 12.1
Common stock sales agreement, commission percentage	3.00%	3.00%
Shares issued | shares			141,678
Common stock, voting right per share | Vote / shares			1
Underwritten Public Offering
Subsidiary, Sale of Stock [Line Items]
Shares issued | shares	2,300,000
Share Price | $ / shares	$ 87
Proceeds from issuance of common stock, gross	$ 200.1
Proceeds from issuance of common stock, net	$ 187.1
2016 Shelf Registration
Subsidiary, Sale of Stock [Line Items]
Shelf Registration Statement, maximum aggregate amount issuable				$ 150
2019 Shelf Registration
Subsidiary, Sale of Stock [Line Items]
Proceeds from issuance of common stock, gross			$ 219.8

Stockholders' Equity - Equity I

Stockholders' Equity - Equity Incentive Plans (Details)	Sep. 30, 2020shares
2015 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grant	4,134,138

Stockholders' Equity - Stock Op

Stockholders' Equity - Stock Option Activity (Details) - USD ($)	9 Months Ended
	Sep. 30, 2020
Number of shares
Beginning balance outstanding (in shares)	3,458,447
Granted (in shares)	642,509
Exercised (in shares)	(123,456)
Forfeited (in shares)	(67,645)
Ending balance outstanding (in shares)	3,909,855
Vested and expected to vest (in shares)	3,903,686
Exercisable (in shares)	2,319,685
Weighted average exercise price
Beginning balance outstanding (in dollars per share)	$ 10.19
Granted (in dollars per share)	54.27
Exercised (in dollars per share)	8.18
Forfeited (in dollars per share)	41.57
Ending balance outstanding (in dollars per share)	16.95
Vested and expected to vest (in dollars per share)	16.98
Exercisable (in dollars per share)	$ 9.99
Weighted average contractual term
Outstanding (in years)	7 years 6 months
Vested and expected to vest (in years)	7 years 6 months
Exercisable (in years)	6 years 2 months 12 days
Aggregate intrinsic value
Outstanding (in dollars)	$ 213,789,330
Vested and expected to vest (in dollars)	213,357,801
Exercisable (in dollars)	$ 142,292,294

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details) $ / shares in Units, $ in Millions	9 Months Ended
	Sep. 30, 2020USD ($)$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-vested options outstanding | shares	11,222
Weighted average
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share) | $ / shares	$ 34.73
Unrecognized compensation cost related to non-vested stock options expected to be recognized | $	$ 26.9
Expected vesting period for non-vested share-based compensation	3 years

Stockholders' Equity - Restrict

Stockholders' Equity - Restricted Stock Units (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Restricted stock units
Compensation cost	$ 2,868,818	$ 1,156,435	$ 9,150,373	$ 3,301,301
Restricted stock units
Restricted stock units
Weighted-average grant date fair value	$ 34.64		$ 34.64
Vesting period			4 years
Compensation cost			$ 4,700,000
Number of shares
Granted (in shares)			156,378
Forfeited (in shares)			(456)
Ending balance outstanding (in shares)	155,922		155,922
Weighted average exercise price
Granted (in dollars per share)			$ 34.67
Forfeited (in dollars pershare)			(45.14)
Ending balance (in dollars per share)	$ 34.64		$ 34.64
Weighted average contractual term
Weighted average contractual term			3 years 8 months 12 days

Stockholders' Equity - Stock-ba

Stockholders' Equity - Stock-based Compensation Expense (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense (income)	$ 2,868,818	$ 1,156,435	$ 9,150,373	$ 3,301,301
Research and development
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense (income)	860,744	286,234	2,532,649	652,666
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense (income)	$ 2,008,074	$ 870,201	$ 6,617,724	$ 2,648,635

Stockholders' Equity - Warrant

Stockholders' Equity - Warrant Activity (Details)	1 Months Ended							3 Months Ended	9 Months Ended
	Sep. 30, 2020D$ / sharesshares	Aug. 31, 2020shares	May 31, 2020USD ($)shares	Dec. 31, 2019$ / sharesshares	Sep. 30, 2019shares	Aug. 31, 2019shares	Mar. 31, 2019$ / sharesshares	Sep. 30, 2020USD ($)$ / sharesshares	Sep. 30, 2020USD ($)$ / sharesshares	Sep. 30, 2020USD ($)$ / sharesshares	Jul. 25, 2019$ / sharesshares	Mar. 31, 2019$ / sharesshares	Nov. 30, 2018$ / sharesshares	Nov. 30, 2016$ / sharesshares
Warrants
Warrants outstanding beginning balance									69,656
Warrants issued									15,541
Warrants exercised									(69,656)
Warrants outstanding ending balance	15,541			69,656				15,541	15,541
Weighted average exercise price
Beginning balance (in dollars per share) | $ / shares									$ 7.21
Issued (in dollars per share) | $ / shares									80.43
Exercised (in dollars per share) | $ / shares									7.21
Ending balance (in dollars per share) | $ / shares	$ 80.43			$ 7.21				$ 80.43	80.43
Exercise price of warrants (in dollars per share) | $ / shares	$ 80.43			$ 7.21				$ 80.43	$ 80.43	$ 80.43
Shares issued									141,678
Loss on extinguishment of debt | $								$ 1,247,012	$ 1,247,012
Original Term Loan 2016
Warrants
Warrants exercised			32,614
Weighted average exercise price
Outstanding warrants | $			$ 29,982
Amended Term Loan 2016
Weighted average exercise price
Shares issued		7,579
2019 Term Loan
Weighted average exercise price
Loss on extinguishment of debt | $									$ 1,200,000
Warrants | Original Term Loan 2016
Warrants
Warrants exercised					32,614
Weighted average exercise price
Warrant term														7 years
Common stock to be issued if warrants are exercised (in shares)														65,228
Exercise price of warrants (in dollars per share) | $ / shares														$ 7.41
Shares issued					24,328
Warrants | Amended Term Loan 2016
Warrants
Warrants exercised		7,875				7,875
Warrants outstanding ending balance	0							0	0
Weighted average exercise price
Warrant term													7 years
Common stock to be issued if warrants are exercised (in shares)													15,750
Exercise price of warrants (in dollars per share) | $ / shares													$ 3.06
Shares issued						6,969
Warrants | Term loan 2020 tranche one
Weighted average exercise price
Ending balance (in dollars per share) | $ / shares	$ 80.43							$ 80.43	$ 80.43
Common stock to be issued if warrants are exercised (in shares)										15,541
Exercise price of warrants (in dollars per share) | $ / shares	$ 80.43							$ 80.43	$ 80.43	$ 80.43
Trading days | D	10
Term of warrants (in years)	7 years
Fair value | $										$ 900,000
Warrants | 2019 Term Loan
Warrants
Warrants issued							58,332
Warrants exercised		29,167		29,167
Warrants outstanding ending balance	0							0	0
Weighted average exercise price
Ending balance (in dollars per share) | $ / shares							$ 8.10
Common stock to be issued if warrants are exercised (in shares)											29,167	70,000
Exercise price of warrants (in dollars per share) | $ / shares							$ 8.10					$ 8.10
Shares issued		26,270		24,185
Fair value | $										$ 400,000
Warrants | Term Loan 2019, Tranche Two
Weighted average exercise price
Common stock to be issued if warrants are exercised (in shares)											5,750
Exercise price of warrants (in dollars per share) | $ / shares											$ 25.71
Warrants issuable in future							11,668

License Agreements (Details)

License Agreements (Details)	1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Jan. 31, 2020USD ($)$ / sharesshares	Sep. 30, 2020USD ($)shares	Sep. 30, 2019USD ($)	Sep. 30, 2020USD ($)shares	Sep. 30, 2019USD ($)	Dec. 31, 2012item	Jan. 09, 2020USD ($)$ / shares	Dec. 31, 2019USD ($)shares
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Number of common shares | shares		37,344,201		37,344,201				36,933,217
Value of common stock		$ 3,733		$ 3,733				$ 3,693
Research and development expense recognized		14,795,493	$ 15,835,573	52,859,850	$ 34,441,796
Pfizer Inc | License Agreements
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Number of common shares | shares	82,019
Value of common stock	$ 8,000,000
Prior trading days	10 days
Share price | $ / shares	$ 97.54
Upfront cash payment	$ 3,000,000
Fair value share price | $ / shares							$ 87.24
Fair value of common stock							$ 7,200,000
Research and development expense recognized				10,200,000
Future milestone payments		$ 323,000,000		323,000,000
Milestone payments or royalties				$ 0
Pfizer Inc | License Agreements | AXS-04
Research and Development Arrangement, Contract to Perform for Others [Line Items]
License agreement royalty as a percent of net sales						1.50%
Antecip | License Agreements
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Number of exclusive license agreements | item						3
License agreement royalty, maximum reduction percent as a result of required third party payments						50.00%
License agreement term, from first commercial sale						10 years
Antecip | License Agreements | AXS-02
Research and Development Arrangement, Contract to Perform for Others [Line Items]
License agreement royalty as a percent of net sales						4.50%
Antecip | License Agreements | AXS-05
Research and Development Arrangement, Contract to Perform for Others [Line Items]
License agreement royalty as a percent of net sales						3.00%