Adamas Pharmaceuticals (ADMS) 10-Q 10 May 21 2021 Q1 Quarterly report Financial data

Cover Page

Cover Page - shares	3 Months Ended
	Mar. 31, 2021	Apr. 30, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2021
Document Transition Report	false
Entity File Number	001-36399
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	42-1560076
Entity Address, Address Line One	1900 Powell Street
Entity Address, Address Line Two	Suite 1000
Entity Address, City or Town	Emeryville
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94608
City Area Code	510
Local Phone Number	450-3500
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	ADMS
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		45,408,095
Entity Registrant Name	Adamas Pharmaceuticals Inc
Entity Central Index Key	0001328143
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (unaudited) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets
Cash and cash equivalents	$ 124,831	$ 71,660
Available-for-sale securities	0	11,705
Accounts receivable, net	12,421	8,042
Inventory	7,536	7,294
Prepaid expenses and other current assets	13,316	13,035
Total current assets	158,104	111,736
Property and equipment, net	1,488	1,598
Operating lease right-of-use assets	6,270	6,657
Available-for-sale securities, non-current	2,605	0
Intangible assets, net	742	0
Prepaid expenses and other non-current assets	38	38
Total assets	169,247	120,029
Current liabilities
Accounts payable	2,770	2,144
Accrued liabilities	20,867	27,164
Current portion of long-term debt	3,580	3,657
Other current liabilities	1,959	1,902
Total current liabilities	29,176	34,867
Long-term debt	126,159	126,307
Long-term portion of operating lease liabilities	5,964	6,453
Other non-current liabilities	2,011	2,378
Total liabilities	163,310	170,005
Commitments and Contingencies (Note 9)
Stockholders’ equity (deficit)
Preferred stock, $0.001 par value — 5,000,000 shares authorized, and zero shares issued and outstanding at March 31, 2021 and December 31, 2020	0	0
Common stock, $0.001 par value — 100,000,000 shares authorized, 45,408,095 and 28,866,956 shares issued and outstanding at March 31, 2021 and December 31, 2020, respectively	50	34
Additional paid-in capital	523,748	455,277
Accumulated other comprehensive loss	(1)	0
Accumulated deficit	(517,860)	(505,287)
Total stockholders’ equity (deficit)	5,937	(49,976)
Total liabilities and stockholders’ equity (deficit)	$ 169,247	$ 120,029

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (unaudited) (Parenthetical) - $ / shares	Mar. 31, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, authorized (in shares)	100,000,000	100,000,000
Common stock, issued (in shares)	45,408,095	28,866,956
Common stock, outstanding (in shares)	45,408,095	28,866,956

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (unaudited) - USD ($) shares in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Revenues:
Total revenues	$ 19,311,000	$ 14,481,000
Costs and operating expenses:
Cost, Product and Service [Extensible List]	Product sales	Product sales
Cost of product sales	$ 385,000	$ 572,000
Research and development	1,812,000	2,465,000
Selling, general and administrative, net	26,639,000	24,552,000
Total costs and operating expenses	28,836,000	27,589,000
Loss from operations	(9,525,000)	(13,108,000)
Interest and other income, net	384,000	84,000
Interest expense	(3,432,000)	(3,624,000)
Net loss	$ (12,573,000)	$ (16,648,000)
Net loss per share, basic and diluted (in dollars per share)	$ (0.36)	$ (0.59)
Weighted average shares used in computing net loss per share, basic and diluted (in shares)	35,167	28,030
Product sales
Revenues:
Total revenues	$ 17,978,000	$ 14,481,000
Royalty revenue
Revenues:
Total revenues	$ 1,333,000	$ 0

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss (unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement of Comprehensive Income [Abstract]
Net loss	$ (12,573)	$ (16,648)
Other comprehensive income (loss)
Unrealized gain (loss) on available-for-sale securities	(1)	57
Total other comprehensive income (loss)	(1)	57
Comprehensive loss	$ (12,574)	$ (16,591)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Stockholders Equity (Deficit) (unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2019		27,964,778
Beginning balance at Dec. 31, 2019	$ (893)	$ 33	$ 446,942	$ 16	$ (447,884)
Increase (decrease) in shareholders' equity
Exercise of stock options (in shares)		61,766
Exercise of stock options	42		42
Restricted stock units vested (in shares)		131,661
Other comprehensive income (loss)	57			57
Stock-based compensation	1,589		1,589
Net loss	(16,648)				(16,648)
Ending balance (in shares) at Mar. 31, 2020		28,158,205
Ending balance at Mar. 31, 2020	(15,853)	$ 33	448,573	73	(464,532)
Beginning balance (in shares) at Dec. 31, 2019		27,964,778
Beginning balance at Dec. 31, 2019	(893)	$ 33	446,942	16	(447,884)
Ending balance (in shares) at Dec. 31, 2020		28,866,956
Ending balance at Dec. 31, 2020	(49,976)	$ 34	455,277	0	(505,287)
Increase (decrease) in shareholders' equity
Issuance of common stock in conjunction with equity offerings, net of commissions and issuance costs (in shares)		15,710,896
Issuance of common stock in conjunction with equity offerings, net of commissions and issuance costs	66,508	$ 16	66,492
Exercise of stock options (in shares)		291,494
Exercise of stock options	202		202
Restricted stock units vested (in shares)		538,749
Other comprehensive income (loss)	(1)			(1)
Stock-based compensation	1,777		1,777
Net loss	(12,573)				(12,573)
Ending balance (in shares) at Mar. 31, 2021		45,408,095
Ending balance at Mar. 31, 2021	$ 5,937	$ 50	$ 523,748	$ (1)	$ (517,860)

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash flows from operating activities
Net loss	$ (12,573)	$ (16,648)
Adjustments to reconcile net loss to net cash used in operating activities
Depreciation	110	236
Stock-based compensation	1,739	1,481
Non-cash interest expense	201	1,582
Change in fair value of embedded derivative liability	(367)	341
Net accretion of discounts and amortization of premiums of available-for-sale securities	(68)	(107)
Provision for write-down of inventory	0	289
Amortization of intangible assets	28	0
Changes in assets and liabilities
Accrued interest of available-for-sale securities	50	218
Accounts receivable, net	(4,379)	23
Inventory	(78)	(234)
Prepaid expenses and other assets	476	33
Operating lease right-of-use assets	387	344
Accounts payable	130	(3,298)
Long-term portion of operating lease liabilities	(451)	(401)
Accrued liabilities and other liabilities	(6,268)	(1,172)
Net cash used in operating activities	(21,063)	(17,313)
Cash flows from investing activities
Purchases of available-for-sale securities	(2,500)	(33,962)
Maturities of available-for-sale securities	11,617	31,000
Acquisition of OSMOLEX ER	(1,327)	0
Net cash provided by (used in) investing activities	7,790	(2,962)
Cash flows from financing activities
Proceeds from public offerings, net of offering costs	66,668	0
Proceeds from issuance of common stock upon exercise of stock options	202	42
Principal payments on long-term debt	(426)	0
Net cash provided by financing activities	66,444	42
Net increase (decrease) in cash and cash equivalents	53,171	(20,233)
Cash and cash equivalents at beginning of period	71,660	65,774
Cash and cash equivalents at end of period	124,831	45,541
Supplemental disclosure of noncash activities
Stock-based compensation capitalized in inventory	38	108
Public offering costs in accounts payable and accrued expense	$ 160	$ 0

DESCRIPTION OF BUSINESS

DESCRIPTION OF BUSINESS	3 Months Ended
	Mar. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
DESCRIPTION OF BUSINESS	DESCRIPTION OF BUSINESS Adamas Pharmaceuticals, Inc. (the “Company”) is a commercial-stage pharmaceutical company focused on growing a portfolio of therapies to address a range of neurological diseases. In August 2017, the U.S. Food and Drug Administration (FDA) approved GOCOVRI ® (amantadine) extended release capsules, the first and only FDA-approved medication indicated for the treatment of dyskinesia in patients with Parkinson’s disease receiving levodopa-based therapy, with or without concomitant dopaminergic medications. In February 2021, the FDA approved a second indication for GOCOVRI for use as an adjunctive treatment to levodopa/carbidopa in patients with Parkinson’s disease experiencing OFF episodes. On January 4, 2021, the Company acquired the global rights to OSMOLEX ER ® (amantadine) extended release tablets from Osmotica Pharmaceuticals US LLC, a subsidiary of Osmotica Pharmaceuticals plc. In November 2012, the Company granted Forest Laboratories Holdings Limited “Forest”, an indirect wholly-owned subsidiary of Allergan plc (collectively “Allergan”) an exclusive license, with right to sublicense, certain of the Company’s intellectual property rights relating to human therapeutics containing memantine in the United States. In connection with these rights, Allergan markets and sells NAMZARIC ® (memantine hydrochloride extended release and donepezil hydrochloride) capsules for the treatment of moderate to severe dementia related to Alzheimer’s disease. In May 2020, the Company became entitled to receive royalties at rates in the low double digits to mid-teens from Allergan for sales of NAMZARIC in the United States. The Company was incorporated in the State of Delaware on November 15, 2000, and operates as one segment. The Company’s headquarters and operations are located in Emeryville, California.

BASIS OF PRESENTATION AND SUMMA

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation The accompanying unaudited condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. The unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) for interim financial information and with instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, these financial statements do not include all of the information and footnotes required by U.S. GAAP for complete financial statements. In the opinion of management, these financial statements include all adjustments (consisting only of normal recurring adjustments) considered necessary for a fair statement of the Company’s condensed consolidated financial statements for the periods presented. The condensed consolidated balance sheet at December 31, 2020 was derived from the audited consolidated financial statements, but does not include all disclosures required by U.S. GAAP. These interim financial results are not necessarily indicative of results to be expected for the full fiscal year ending December 31, 2021, or any other future period. Readers should read these interim unaudited condensed consolidated financial statements in conjunction with the audited consolidated financial statements and the related notes thereto for the year ended December 31, 2020, included in the Company’s Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission, or SEC. The Company’s significant accounting policies are detailed in its Annual Report on Form 10-K for the year ended December 31, 2020. During the three months ended March 31, 2021, other than the business combinations and intangible assets policies described below, the Company’s significant accounting policies have not changed materially from December 31, 2020. Use of Estimates The preparation of the accompanying condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities and the reported amounts of revenues and expenses in the condensed consolidated financial statements and the accompanying notes. On an ongoing basis, management evaluates its estimates, including those related to revenue recognition and variable consideration, lease assets and liabilities, clinical trial accruals, fair value of assets and liabilities including short-term and long-term classification, embedded derivatives, income taxes, inventory, and stock-based compensation. Management bases its estimates on historical experience and on various other market-specific and relevant assumptions that management believes to be reasonable under the circumstances. Actual results may differ from those estimates. Risks and Uncertainties Despite the roll-out of vaccines, the outbreak of the novel Coronavirus (“COVID-19”) is continuing both within the U.S. and globally. The Company is subject to risks and uncertainties as a result of the outbreak of COVID-19. Despite disruptions to the Company’s business operations, the COVID-19 pandemic did not significantly impact GOCOVRI prescription refill rates for the three months ended March 31, 2021, and thus far management has observed no disruptions to its inventory on hand or planned manufacturing schedule. However, new prescription rates have been impacted due to several factors, including: a fluid environment in which office practices are changing frequently including many healthcare providers have temporarily closed their offices or are restricting patient visits; patients are postponing visits to healthcare provider facilities; and the sales force continues to operate in a mix of virtual and live interactions with healthcare providers, adapting to the local environment. While management believes this initial decline and continued impact on new prescriptions to be temporary, the duration and severity is dependent on future developments, including new information that may emerge concerning the actions taken to contain or prevent further spread, all of which are highly uncertain and cannot be predicted with confidence. As of the date of issuance of these condensed consolidated financial statements, due to the numerous uncertainties surrounding the COVID-19 pandemic, the Company is unable to predict the extent to which the COVID-19 pandemic may materially adversely affect the Company’s future business, financial results, liquidity and cash flows. Liquidity Since January 1, 2019, the Company has funded its operations primarily through sales of GOCOVRI, through sales of its common stock, and to a lesser extent through royalties received on net sales of NAMZARIC and sales of OSMOLEX ER. The Company made GOCOVRI available for physician and patient use in the fourth quarter of 2017, with a full commercial launch in January 2018. Prior to the generation of revenue from GOCOVRI, the Company had not generated any commercial revenue from the sale of its products. In November 2019, the Company entered into a sales agreement with Cowen and Company, LLC, pursuant to which it may, from time to time, issue and sell shares of common stock having an aggregate offering value of up to $50.0 million. As of March 31, 2021, the Company had issued 1,553,299 shares of common stock and raised net proceeds of $8.3 million under the sales agreement. In March 2021, the Company completed a follow-on public offering of 14,375,000 shares of common stock, which includes the exercise in full by the underwriters of their option to purchase 1,875,000 shares of common stock, at an offering price of $4.40 per share. Proceeds from the follow-on public offering were approximately $59.3 million, net of underwriting discounts and offering-related transaction costs. As of March 31, 2021, the Company had $127.4 million of cash, cash equivalents, and investments, which management believes will be sufficient to fund its projected operating requirements for at least 12 months from the issuance of these condensed consolidated financial statements. However, it is possible that the Company will not achieve the progress it expects, because revenues from GOCOVRI may be less than anticipated, especially in light of the current COVID-19 pandemic. Business Combinations The Company accounts for business combinations using the acquisition method of accounting, pursuant to ASC Topic 805. This method requires, among other things, that results of operations of acquired companies are included in the Company’s financial results beginning on the respective acquisition date, and that assets acquired and liabilities assumed are recognized separately at their fair value as of the acquisition date. Any excess of the fair value of consideration transferred (the “Purchase Price”) over the fair values of the net assets acquired is recognized as goodwill. The determination of estimated fair value requires the use of significant estimates and assumptions. The fair value of assets acquired and liabilities assumed may be subject to adjustment within the measurement period, which may be up to 12 months from the acquisition date. Transaction costs associated with business combinations are expensed when incurred. Intangible Assets Intangible assets acquired in a business combination are stated at initial fair value less accumulated amortization. Intangible assets with a definite useful life are amortized on a straight-line basis over the estimated useful life of the related assets and are reviewed for impairment whenever events or changes in circumstances indicate that the carrying value of an asset may not be recoverable. Recent Accounting Pronouncements Accounting Pronouncements Adopted in 2021 In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740)—Simplifying the Accounting for Income Taxes . ASU 2019-12 removes certain exceptions to the general principles in Topic 740 and amends existing guidance to improve consistent application. This guidance became effective for the Company on January 1, 2021, and did not have a material impact on its condensed consolidated financial statements. New Accounting Pronouncements Not Yet Adopted In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses of Financial Instruments; in November 2018 the FASB issued a subsequent amendment ASU No. 2018-19, Codification Improvements to Topic 326, Financial Instruments—Credit Losses ; in April 2019 the FASB issued ASU No. 2019-04, Codification Improvements to Topic 326, Financial Instruments—Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments ; in May 2019 the FASB issued ASU No. 2019-05, Financial Instruments—Credit Losses (Topic 326): Targeted Transition Relief ; and in November 2019 the FASB issued ASU No. 2019-11, Codification Improvements to Topic 326, Financial Instruments—Credit Losses . The new guidance changes the methodology for measuring credit losses on financial instruments and the timing of when such losses are recorded. In November 2019 the FASB issued ASU No. 2019-10, Financial Instruments—Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842)—Effective Dates , which defers the effective date of ASU 2016-13 for all entities except SEC reporting companies that are not smaller reporting companies. As a smaller reporting company, this guidance is effective for fiscal years beginning after December 15, 2022. Early adoption is permitted. The Company is currently evaluating the timing and effect the new guidance will have on its consolidated financial statements.

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS	FAIR VALUE MEASUREMENTS In accordance with ASC 820-10, Fair Value Measurements and Disclosures, the Company determines the fair value of financial and non-financial assets and liabilities using the fair value hierarchy, which establishes three levels of inputs that may be used to measure fair value, as follows: • Level 1 inputs, which include quoted prices in active markets for identical assets or liabilities; • Level 2 inputs, which include observable inputs other than Level 1 inputs, such as quoted prices for similar assets or liabilities, quoted prices for identical or similar assets or liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the asset or liability. For available-for-sale securities, the Company reviews trading activity and pricing as of the measurement date. When sufficient quoted pricing for identical securities is not available, the Company uses market pricing and other observable market inputs for similar securities obtained from various third-party data providers. These inputs either represent quoted prices for similar assets in active markets or have been derived from observable market data; and • Level 3 inputs, which include unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the underlying asset or liability. Level 3 assets and liabilities include those whose fair value measurements are determined using pricing models, discounted cash flow methodologies, or similar valuation techniques, as well as significant management judgment or estimation. The following table represents the fair value hierarchy for the Company’s financial assets and liabilities which require fair value measurement on a recurring basis (in thousands): March 31, 2021 Total Level 1 Level 2 Level 3 Assets: Money market $ 116,718 $ 116,718 $ — $ — Corporate debt 2,605 — 2,605 — Total assets measured at fair value $ 119,323 $ 116,718 $ 2,605 $ — Liabilities: Embedded derivative liability $ 2,011 $ — $ — $ 2,011 Total liabilities measured at fair value $ 2,011 $ — $ — $ 2,011 December 31, 2020 Total Level 1 Level 2 Level 3 Assets: Money market $ 48,152 $ 48,152 $ — $ — Corporate debt 6,706 — 6,706 — U.S. Treasury securities 4,999 — 4,999 — Total assets measured at fair value $ 59,857 $ 48,152 $ 11,705 $ — Liabilities: Embedded derivative liability $ 2,378 $ — $ — $ 2,378 Total liabilities measured at fair value $ 2,378 $ — $ — $ 2,378 Money market funds are highly liquid investments and are actively traded. The pricing information on these investment instruments are readily available and can be independently validated as of the measurement date. This approach results in the classification of these securities as Level 1 of the fair value hierarchy. Corporate debt, U.S. Treasury securities, and commercial paper are measured at fair value using Level 2 inputs. The Company reviews trading activity and pricing for these investments as of each measurement date. When sufficient quoted pricing for identical securities is not available, the Company uses market pricing and other observable market inputs for similar securities obtained from various third-party data providers. These inputs represent quoted prices for similar assets in active markets or these inputs have been derived from observable market data. This approach results in the classification of these securities as Level 2 of the fair value hierarchy. In certain cases where there is limited activity or less transparency around inputs to valuation, the related assets or liabilities are classified as Level 3. The Company classified an embedded derivative related to its royalty-backed loan agreement (“Royalty-Backed Loan”) with HealthCare Royalty Partners III, L.P. (“HCR”) as a Level 3 liability. The fair value of the embedded derivative as a result of a change in control was calculated using a probability-weighted discounted cash flow model. The model used in valuing this embedded derivative requires the use of significant estimates and assumptions including but not limited to: 1) expected cash flows the Company expects to receive on U.S. net sales of GOCOVRI and OSMOLEX ER and on royalties from Allergan on U.S. net sales of NAMZARIC; 2) the Company’s risk adjusted discount rates; and 3) the probability of a change in control occurring during the term of the note based on the percentage of similar companies that were acquired over the previous five year period. Changes in the estimated fair value of the bifurcated embedded derivative are reported as gains or losses in interest and other income, net, in the condensed consolidated statements of operations. In the periods presented, the Company evaluated the embedded derivative value as a result of an event of default and the value as a result of increased costs due to a regulatory change and considered both to have no material value based on current assessment of probability, but could become material in future periods if a specified event of default or regulatory change became more probable than is currently estimated. See “Note 10. Long-Term Debt” for further description. At March 31, 2021, the embedded derivative related to the Royalty-Backed Loan was the only recurring fair value measurement with Level 3 unobservable inputs. A risk-adjusted discount rate of 16.8% and a probability of a change in control of 3.0% were applied to calculate the value of the embedded derivative. Significant increases (or decreases) in the discount rate, and significant increases (or decreases) in the probability of a change in control would result in a significantly higher (or lower) fair value measurement. The following table sets forth changes in Level 3 liabilities measured at fair value on a recurring basis for the three months ended March 31, 2021 and 2020 (in thousands): Three Months Ended March 31, 2021 2020 Beginning balance $ 2,378 $ 2,157 Change in fair value included in interest and other income, net (367) 341 Ending balance $ 2,011 $ 2,498 There were no transfers into or out of Level 3 during the three months ended March 31, 2021 and 2020.

INVESTMENTS

INVESTMENTS	3 Months Ended
	Mar. 31, 2021
Investments, Debt and Equity Securities [Abstract]
INVESTMENTS	INVESTMENTS The Company’s investments consist of corporate debt, U.S. Treasury securities, and commercial paper classified as available-for-sale securities. The Company limits the amount of investment exposure as to institution, maturity, and investment type. To mitigate credit risk, the Company invests in investment grade corporate debt, U.S. Treasury securities, and commercial paper. Such securities are reported at fair value, with unrealized gains and losses excluded from earnings and shown separately as a component of accumulated other comprehensive income (loss) within stockholders’ equity. Realized gains and losses are reclassified from other comprehensive income (loss) to other income on the condensed consolidated statements of operations when incurred. The Company may pay a premium or receive a discount upon the purchase of available-for-sale securities. Interest earned and gains realized on available-for-sale securities and amortization of discounts received and accretion of premiums paid on the purchase of available-for-sale securities are included in investment income. The following table is a summary of amortized cost, unrealized gain and loss, and the fair value of available-for-sale securities as of March 31, 2021 and December 31, 2020 (in thousands): March 31, 2021 Amortized Cost Gross Unrealized Gross Unrealized Fair Value Investments: Corporate debt $ 2,606 $ — $ (1) $ 2,605 Total $ 2,606 $ — $ (1) $ 2,605 Reported as: Long-term investments $ 2,606 $ — $ (1) $ 2,605 Total $ 2,606 $ — $ (1) $ 2,605 December 31, 2020 Amortized Cost Gross Unrealized Gross Unrealized Fair Value Investments: Corporate debt $ 6,706 $ — $ — $ 6,706 U.S. Treasury securities 4,999 — — 4,999 Total $ 11,705 $ — $ — $ 11,705 Reported as: Short-term investments $ 11,705 $ — $ — $ 11,705 Total $ 11,705 $ — $ — $ 11,705

INVENTORY

INVENTORY	3 Months Ended
	Mar. 31, 2021
Inventory Disclosure [Abstract]
INVENTORY	INVENTORY If the Company identifies excess, obsolete, or unsalable product, the Company will write down its inventory to net realizable value in the period it is identified. During the three months ended March 31, 2021 and 2020, the Company recorded a provision for the write-down of inventory to cost of product sales of zero and $0.3 million, respectively. Inventory consists of the following (in thousands): March 31, 2021 December 31, 2020 Raw materials $ 780 $ 795 Work-in-process 4,095 4,403 Finished goods 2,661 2,096 Total inventory $ 7,536 $ 7,294

INTANGIBLE ASSETS, NET

INTANGIBLE ASSETS, NET	3 Months Ended
	Mar. 31, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
INTANGIBLE ASSETS, NET	INTANGIBLE ASSETS, NET The Company recognized intangible assets in connection with the acquisition of OSMOLEX ER, which is being amortized over its useful life of seven years. See “Note 8. Acquisition of OSMOLEX ER” for further description of the OSMOLEX ER acquisition. Amortization expense is included in cost of product sales in the condensed consolidated statements of operations. Intangible assets, net, consist of the following (in thousands): March 31, 2021 December 31, 2020 Developed product $ 770 $ — Accumulated amortization (28) — Total intangible assets, net $ 742 $ — Amortization expense for the three months ended March 31, 2021 was $28,000. Estimated amortization expense for the remainder of 2021 and for each of the five succeeding years ending December 31 will be as follows (in thousands): Year Amount 2021 (remainder) $ 82 2022 110 2023 110 2024 110 2025 110 2026 110 Thereafter 110 Total amortization expense $ 742

LICENSE AGREEMENTS

LICENSE AGREEMENTS	3 Months Ended
	Mar. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
LICENSE AGREEMENTS	LICENSE AGREEMENTSIn November 2012, the Company granted Forest Laboratories Holdings Limited “Forest”, an indirect wholly-owned subsidiary of Allergan plc (collectively “Allergan”) an exclusive license, with right to sublicense, certain of the Company’s intellectual property rights relating to human therapeutics containing memantine in the United States. In connection with these rights, Allergan markets and sells NAMZARIC and NAMENDA XR for the treatment of moderate to severe dementia related to Alzheimer’s disease. Pursuant to the agreement, Allergan made an upfront payment of $65.0 million. The Company earned and received additional cash payments totaling $95.0 million upon achievement by Allergan of certain development and regulatory milestones. Under the agreement, external costs incurred related to the prosecution and litigation of intellectual property rights are reimbursable. Reimbursable external costs are recorded as a reduction to selling, general and administrative, net. For the three months ended March 31, 2021 and 2020, there were no reimbursable external costs for prosecution or litigation of intellectual property rights. In addition, the Company may earn tiered royalty payments based on net sales of NAMZARIC and NAMENDA XR. Beginning in May 2020, the Company became entitled to receive royalties at rates in the low double digits to mid-teens from Allergan for sales of NAMZARIC in the United States. The Company recognized $1.3 million in NAMZARIC royalty revenue for the three months ended March 31, 2021, and recognized no royalty revenue for the three months ended March 31, 2020. Allergan’s obligation to pay royalties with respect to fixed-dose memantine-donepezil products, including NAMZARIC, continues until the later of (i) 15 years after the commercial launch of the first fixed-dose memantine-donepezil product by Allergan in the United States or (ii) the expiration of the Orange Book listed patents for which Allergan obtained rights from the Company covering such product, but is eliminated in any quarter where there is significant competition from generics. Based on Allergan’s and the Company’s current settlement agreements with the NAMZARIC ANDA filers to date, the earliest date on which any of these agreements grant a license to market a NAMZARIC ANDA filer’s generic version of NAMZARIC is January 1, 2025 (or earlier in certain circumstances). Alternatively, the NAMZARIC ANDA filers with the earliest license date have the option to launch an authorized generic version of NAMZARIC beginning on January 1, 2026 instead of launching their own generic version of NAMZARIC on January 1, 2025. For further discussion of NAMZARIC ANDA filers, see Litigation and Other Legal Proceedings in “Note 9. Commitments and Contingencies.” Beginning in June 2018, the Company was entitled to receive royalties at rates in the low to mid-single digits for sales of NAMENDA XR in the United States. The Company does not expect to receive royalties on net sales of NAMENDA XR, due to the entry of generic versions of NAMENDA XR. Royalties under the license agreement will be recognized when the related sales occur, in accordance with the sales-based royalty exception.

ACQUISITION OF OSMOLEX ER

ACQUISITION OF OSMOLEX ER	3 Months Ended
	Mar. 31, 2021
Business Combinations [Abstract]
ACQUISITION OF OSMOLEX ER	ACQUISITION OF OSMOLEX ER The Company entered into a purchase agreement (the “Asset Purchase Agreement”) with Osmotica Pharmaceutical US LLC and Vertical Pharmaceuticals LLC (“Osmotica”) on December 1, 2020. The transaction closed on January 4, 2021 and settles all previously disclosed patent disputes. Pursuant to the Asset Purchase Agreement: both parties gave each other mutual releases and agreed to dismiss their respective claims relating to certain patent litigation; the Company acquired the global rights to OSMOLEX ER and existing inventory and the assumption of certain liabilities; and Osmotica will not engage in the U.S. in the development, manufacture, or sale of any product that is a generic version of any dosage strength of OSMOLEX ER for a period of five years from the closing of the Asset Purchase Agreement. At closing, the Company paid $7.3 million, including a $7.5 million base purchase price less $0.2 million for the assumption of certain liabilities. Management determined that the Asset Purchase Agreement was to be accounted for as a multiple element arrangement in which $5.2 million represented a patent litigation settlement, $0.8 million represented compensation to Osmotica for future inventory, and $1.3 million represented the acquisition of OSMOLEX ER. The patent litigation settlement was recorded in selling, general and administrative, net, during the twelve months ended December 31, 2020. Compensation to Osmotica for future inventory was recorded as prepaid expenses and other current assets during the three months ended March 31, 2021. The acquisition of OSMOLEX ER was accounted for as a business combination using the acquisition method of accounting during the three months ended March 31, 2021. The following table summarizes the allocation of the purchase price to the fair values of assets acquired and liabilities assumed as of the acquisition date (in thousands): January 4, 2021 Prepaid expenses and other current assets $ 757 Intangible assets - developed product 770 Accrued liabilities (200) Total fair value of assets acquired and liabilities assumed $ 1,327 Intangible assets - developed product consists of OSMOLEX ER registered patents and related intellectual property. The intangible assets acquired were recorded at fair value using the multi-period excess earnings method, or MPEEM. The MPEEM, a variation of the income approach, estimates an intangible asset’s fair value based on the incremental after-tax cash flows attributable only to the intangible asset, discounted to present value using a discount rate based on the Company’s weighted average cost of capital. The Company incurred approximately $0.2 million in acquisition-related expenses, which were recorded in selling, general and administrative, net in the condensed consolidated statements of operations. The results of operations of OSMOLEX ER have been included in the condensed consolidated statements of operations since the acquisition date of January 4, 2021. Since January 4, 2021 and through March 31, 2021, OSMOLEX ER contributed $0.3 million to the Company’s net product sales. Total earnings contributed by OSMOLEX ER was not separately identifiable and is impracticable to disclose as the operations of OSMOLEX ER were integrated into the operations of the Company from the date of acquisition and not accounted for separately. Pro forma financial information is not presented as historical financial results of OSMOLEX ER are not significant when compared to the actual results of operations of the Company.

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	3 Months Ended
	Mar. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Purchase Commitments The Company has entered into agreements for the supply of active pharmaceutical ingredients with Moehs Ibérica, S.L. and AMSA S.p.A., and the manufacture of commercial supply of GOCOVRI with Catalent Pharma Solutions, LLC. Under the terms of the agreements, the Company will supply the vendors with non-cancelable firm commitment purchase orders. The Company has also entered into other agreements with certain vendors for the provision of services, including services related to data access and packaging, under which the Company is contractually obligated to make certain payments to the vendors. The Company enters into contracts in the normal course of business that include, among others, arrangements with CROs for clinical trials, vendors for preclinical research, and vendors for manufacturing. These contracts generally provide for termination upon notice, and therefore the Company believes that its obligations under these agreements are not material. Contingencies In the normal course of business, the Company enters into contracts and agreements that contain a variety of representations and warranties and provide for general indemnifications. The Company’s exposure under these agreements is unknown, because it involves claims that may be made against the Company in the future, but have not yet been made. The Company accrues a liability for such matters when it is probable that future expenditures will be made and such expenditures can be reasonably estimated. Indemnification In accordance with the Company’s amended and restated certificate of incorporation and amended and restated bylaws, the Company has indemnification obligations to its officers and directors for certain events or occurrences, subject to certain limits, while they are serving in such capacity. The Company has a directors and officers liability insurance policy that may enable it to recover a portion of any amounts paid for claims. In addition, in the normal course of business, the Company enters into contracts and agreements that may contain a variety of representations and warranties and provide for general indemnifications. Litigation and Other Legal Proceedings In November 2012, the Company granted Forest an exclusive license to certain of the Company’s intellectual property rights relating to human therapeutics containing memantine in the United States. Under the terms of that license agreement, Forest has the right to enforce such intellectual property rights which are related to its right to market and sell NAMZARIC and NAMENDA XR for the treatment of moderate to severe dementia related to Alzheimer’s disease. The Company has a right to participate in, but not control, such enforcement actions by Forest. In 2018 and as of the issuance date of these condensed consolidated financial statements, multiple generic companies have launched generic versions of NAMENDA XR. As of the issuance date of these condensed consolidated financial statements, a number of companies have submitted ANDAs including one or more certifications pursuant to 21 U.S.C. § 355(j)(2)(A)(vii)(iv) to the FDA requesting approval to manufacture and market generic versions of NAMZARIC, on which the Company is entitled to receive royalties from Forest beginning in May 2020. As of the issuance date of these condensed consolidated financial statements, the Company and Forest have settled with all such NAMZARIC ANDA filers, including all first filers on all the available dosage forms of NAMZARIC. Subject to those agreements, the earliest date on which any of these agreements grant a license to market a NAMZARIC ANDA filer’s generic version of NAMZARIC is January 1, 2025 (or earlier in certain circumstances). Alternatively, the NAMZARIC ANDA filers with the earliest date have the option to launch an authorized generic version of NAMZARIC beginning on January 1, 2026 instead of launching their own generic version of NAMZARIC on January 1, 2025. The Company and Forest intend to continue to enforce the patents associated with NAMZARIC. On July 1, 2020, the Company received a letter dated June 29, 2020, notifying the Company that Zydus Worldwide DMCC (“Zydus Worldwide”) submitted to the FDA an ANDA for Amantadine Extended-Release Capsules, 68.5 mg and 137 mg that contains certifications pursuant to 21 U.S.C. § 355(j)(2)(A)(vii)(IV) with respect to the Company’s U.S. Patent Nos. 8,389,578; 8,741,343; 8,796,337; 8,889,740; 8,895,614; 8,895,615; 8,895,616; 8,895,617; 8,895,618; 9,867,791; 9,867,792; 9,867,793; 9,877,933; and 10,154,971, that these patents are invalid or will not be infringed by the manufacture, use or sale of Zydus Worldwide’s Amantadine Extended-Release Capsules, 68.5 mg and 137 mg. On August 13, 2020, the Company filed a lawsuit against Zydus Worldwide and Zydus Pharmaceuticals (USA), Inc. (collectively “Zydus”) alleging infringement of those patents and U.S. Patent No. 10,646,456 by Zydus in the United States District Court for the District of New Jersey. U.S. Patent No. 10,646,456 was not listed in the Orange Book at the time Zydus Worldwide filed its ANDA, but on or about September 3, 2020, the Company received a letter dated September 2, 2020, notifying the Company that Zydus Worldwide submitted a certifications pursuant to 21 U.S.C. § 355(j)(2)(A)(vii)(IV) with respect to the Company’s U.S. Patent No. 10,646,456 with respect to its ANDA for Amantadine Extended-Release Capsules, 68.5 mg and 137 mg. On January 30, 2021, Adamas Pharma, LLC entered into a definitive agreement (the “Settlement Agreement”) with Zydus pursuant to which the parties agreed to end the lawsuit and dismiss it without prejudice, and the Court dismissed the lawsuit on February 3, 2021. Pursuant to the Settlement Agreement, Adamas Pharma, LLC grants Zydus a license to make, use, sell, offer to sell and import a generic version of GOCOVRI (amantadine) extended release capsules (including for any new indications approved under the GOCOVRI NDA), effective as of March 4, 2030, or earlier in certain circumstances typical for such agreements. The Settlement Agreement contains provisions that may accelerate the license date, including if unit sales of GOCOVRI for the 12-month period ending July 31, 2025 or any subsequent 12-month period decline by a specified percentage below GOCOVRI unit sales for the year ended December 31, 2019. The Company and Adamas Pharma LLC intend to continue to enforce the patents associated with GOCOVRI. On April 1, 2019, the Company was served with a complaint filed in the United States District Court for the Northern District of California (Case No. 3:18-cv-03018-JCS) against the Company and several Allergan entities alleging violations of Federal and state false claims acts (“FCA”) in connection with the commercialization of NAMENDA XR and NAMZARIC by Allergan. The lawsuit is a qui tam complaint brought by a named individual, Zachary Silbersher, asserting rights of the Federal government and various state governments. The lawsuit was originally filed in May 2018 under seal, and the Company became aware of the lawsuit when it was served. The complaint alleges that patents held by Allergan and the Company covering NAMENDA XR and NAMZARIC were procured through fraud on the United States Patent and Trademark Office and that these patents were asserted against potential generic manufacturers of NAMENDA XR and NAMZARIC to prevent the generic manufacturers from entering the market, thereby wrongfully excluding generic competition resulting in an artificially high price being charged to government payors. The Company’s patents in question were licensed exclusively to Forest. The complaint includes a claim for damages of “potentially more than $2.5 billion dollars,” treble damages “under the federal FCA and most of the State FCAs,” and “statutory penalties that can be assessed for each false claim.” This action is ongoing. The federal and state governments have declined to intervene in this action. To the Company’s knowledge, the individual plaintiff is pursuing the lawsuit in his individual capacity. This case is currently stayed pending the Company and Allergan’s interlocutory appeal of the District Court’s December 11, 2020 order denying the Company’s and Allergan’s motion to dismiss the complaint. The appeal is pending in the United States Court of Appeals for the Ninth Circuit (Case No. 21-80005). The Company believes it has strong factual and legal defenses and intends to defend itself vigorously. On May 13, 2019, a putative class action lawsuit alleging violations of the federal securities laws was filed by Plymouth County Contributory Retirement System against the Company and certain of the Company’s current and former directors and officers in California Superior Court for the County of Alameda (Case No. RG19018715). The lawsuit alleges violations of the Securities Act of 1933 by the Company and certain of the Company’s current and former directors and officers for allegedly making false statements and omissions in the registration statement and prospectus filed by the Company in connection with its January 24, 2018, secondary public offering of common stock. On October 29, 2020, Adamas signed a Memorandum of Understanding to settle this lawsuit for a payment of $7.5 million to eligible settlement class members in resolution of claims asserted against the Company, its officers, directors, and the other defendants. The settlement will be paid by the Company’s Director & Officer liability insurance. The Company and the other defendants continue to deny each of the plaintiff’s claims and deny any liability, but the Company agreed to the settlement solely to resolve the disputes, to avoid the costs and risks of further litigation, and to avoid further distractions to management. This settlement received final approval from the court on April 13, 2021. On December 10, 2019, another putative class action lawsuit alleging violations of the federal securities laws was filed by Ali Zaidi against the Company and certain of the Company’s current and former directors and officers in federal court in the Northern District of California (Case No. 4:19-cv-08051). This lawsuit alleges violations of the Securities Exchange Act of 1934 by the Company and certain of the Company’s current and former officers. On March 16, 2020, a shareholder derivative lawsuit was filed by Patrick Van Camp in federal court in the Northern District of California (Case No. 4:20-cv-01815) naming the Company and certain of the Company’s current and former directors and officers as defendants. This lawsuit alleges breaches of fiduciary duty and violations of the Securities Exchange Act of 1934 by certain of the Company’s current and former directors and officers. The Company is named as a nominal defendant only. On April 6, 2020, another, virtually identical, shareholder derivative lawsuit was filed by James Druzbik in federal court in the Northern District of California (Case No. 4:20-cv-02320) naming the Company and certain of the Company’s current and former directors and officers as defendants. This lawsuit contains the same allegations, claims, and defendants as the first derivative action. The Company is named as a nominal defendant only. Other similar cases may be filed in the future. In all of these actions, Plaintiffs seek unspecified monetary damages and other relief. These actions are ongoing. The Company believes it has strong factual and legal defenses to all actions and intends to defend itself vigorously. From time to time, the Company may be party to legal proceedings, investigations, and claims in the ordinary course of its business. Other than the matters described above, the Company is not currently party to any material legal proceedings.

LONG-TERM DEBT

LONG-TERM DEBT	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
LONG-TERM DEBT	LONG-TERM DEBT Royalty-Backed Loan Agreement In May 2017, the Company, through a new wholly-owned subsidiary, Adamas Pharma, LLC, entered into a Royalty-Backed Loan with HCR, whereby the Company initially borrowed $35 million, followed by an additional $65 million received in the fourth quarter 2017 upon FDA’s recognition in the Orange Book of seven-year orphan drug exclusivity, which GOCOVRI earned upon approval on August 24, 2017. On December 1, 2020, the Company entered into an agreement with HCR to amend certain key terms of the Royalty-Backed Loan to be effective upon the closing of the Company’s Asset Purchase Agreement with Osmotica. The Asset Purchase Agreement closed on January 4, 2021, and is described further in “Note 8. Acquisition of OSMOLEX ER.” The amendment of the Royalty-Backed Loan was accounted for prospectively as a debt modification, based on a comparison of the present value of the cash flows under the terms of the debt immediately before and after the amendment, which resulted in a change that was not substantially different. Principal and interest will be payable quarterly from the proceeds of a 12.5% royalty on U.S. net sales of GOCOVRI and OSMOLEX ER, and up to $15 million of the Company’s annual royalties from Allergan on U.S. net sales of NAMZARIC starting in May 2020, pursuant to the Company’s license agreement with Allergan. The royalty rate on net sales of GOCOVRI will drop to 6.25% after the principal amount of the loan has been repaid in full, until the Company has made total payments of 200% of the funded amounts. The Company may elect to voluntarily prepay the loan at any time, or may be required to prepay subject to specified prepayment trigger events as described below. In the case of the occurrence of a change in control: the amount due will be $175 million, less total payments made to date, if such prepayment is made on or prior to December 31, 2022; or $195 million, less total payments to date, if made thereafter. In the case of the occurrence of any event of default the amount due will be 200% of the funded amounts, less total payments made to date. Royalty rates are subject to increase to 22.5% if total principal and interest payments have not reached minimum specified levels at the measurement date of December 2022. Under the terms of the loan, HCR has recourse to Adamas Pharma, LLC, not the Company. The loan agreement matures in March 2027 but as the repayment of the loan amount is contingent upon the sales volumes of GOCOVRI and OSMOLEX ER, and royalties from Allergan, the repayment term may be shortened depending on the actual sales of GOCOVRI and OSMOLEX ER, and actual royalties received from Allergan. The loans bear interest at an annual rate of 11% on the outstanding principal amount and includes an interest-only period until the interest payment date following the ninth full calendar quarter after the $65 million additional loan received in the fourth quarter 2017. To the extent that royalties were insufficient to pay interest in full during the first nine quarters of the loan, any unpaid portion of the quarterly interest payment was added to the principal amount of the loans. This payment-in-kind period ended in the first quarter of 2020. In connection with the Royalty-Backed Loan, in 2017 the Company paid HCR a lender expense amount of $0.4 million and incurred additional debt issuance costs totaling $0.8 million. The lender expense and additional debt issuance costs have been recorded as a debt discount. The unamortized debt discount as of the date of the modification is being amortized and recorded as interest expense over the estimated term of the loan using the effective interest method. Issuance costs paid to the lender in connection with the amendment were de minimis. Issuance costs paid to third parties in connection with the amendment were recorded in selling, general and administrative, net, during the twelve months ended December 31, 2020. The Company recorded interest expense, including amortization of the debt discount, related to the Royalty-Backed Loan, of $3.4 million for the three months ended March 31, 2021 and $3.6 million for the three months ended March 31, 2020. Interest expense over the life of the Royalty-Backed Loan includes an annual interest rate of 11% on the outstanding principal, a royalty rate of 6.25% on net sales of GOCOVRI and OSMOLEX ER after the principal amount is paid, and amortization of the debt discount. The effective interest rate, including the amortization of the debt discount, which was changed on a prospective basis in connection with the amendment, was 13.0% as of March 31, 2021. The assumptions used in determining the expected repayment term of the loan and amortization period of the debt discount require that the Company make estimates that could impact the short and long-term classification of these costs, as well as the period over which these costs will be amortized and the effective interest rate. The Company may be required to make mandatory prepayments of the borrowings under the Royalty-Backed Loan upon the occurrence of specified prepayment trigger events, including: (1) the occurrence of any event of default or (2) the occurrence of a change in control. Upon the prepayment of all or any of the outstanding principal balance, the Company shall pay, in addition to such prepayment, a prepayment premium. As HCR, as the holder of the loans, may exercise the option to require prepayment by the Company, the prepayment premium is considered to be an embedded derivative which is required to be bifurcated from its host contract and accounted for as a separate financial instrument. The valuation of the embedded derivative is described further in “Note 3. Fair Value Measurements.” Payment obligations under the Royalty-Backed Loan are as follows (in thousands): March 31, 2021 December 31, 2020 Total repayment obligation $ 200,000 $ 200,000 Less: Interest to be accreted in future periods (45,798) (49,230) Less: Payments made (24,463) (20,806) Carrying value of loans payable $ 129,739 $ 129,964 Less: Current portion of long-term debt (3,580) (3,657) Non-current portion of long-term debt $ 126,159 $ 126,307 The estimated fair value of the long-term debt, as measured using Level 3 inputs, approximates $113.2 million as of March 31, 2021. The estimated fair value was calculated in the same methodology as the valuation of the embedded derivative as described further in “Note 3. Fair Value Measurements.” There are no contractual minimum principal payments due until the loan matures in March 2027 as the repayment of the loan amount is contingent upon the sales volumes of GOCOVRI and OSMOLEX ER, and royalties from Allergan on U.S. net sales of NAMZARIC. Paycheck Protection Program On April 15, 2020, the Company received proceeds from a loan in the amount of $2.7 million (the “PPP Loan”) from JPMorgan Chase Bank, N.A. (the “Lender”), pursuant to the Small Business Association (“SBA”) Paycheck Protection Program (or “PPP”) of the Coronavirus Aid, Relief, and Economic Security Act (the “CARES Act”). At the time the Company applied for the PPP loan, the Company believed it qualified to receive the funds pursuant to the then published qualification requirements. On April 23, 2020, the SBA, in consultation with the Department of Treasury, issued new guidance regarding qualification requirements for public companies. Based on the Company’s assessment of the new guidance, on April 29, 2020, the Company repaid the principal and interest on the PPP loan.

STOCKHOLDERS_ EQUITY

STOCKHOLDERS’ EQUITY	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
STOCKHOLDERS’ EQUITY	STOCKHOLDERS’ EQUITY Common Stock The amended and restated certificate of incorporation authorizes the Company to issue 100,000,000 shares of common stock. Common stockholders are entitled to dividends as and when declared by the board of directors, subject to the rights of holders of all classes of stock outstanding having priority rights as to dividends. There have been no dividends declared to date. Each share of common stock is entitled to one vote. Public Offering In March 2021, the Company completed a follow-on public offering of 14,375,000 shares of common stock, which includes the exercise in full by the underwriters of their option to purchase 1,875,000 shares of common stock, at an offering price of $4.40 per share. Proceeds from the follow-on public offering were approximately $59.3 million, net of underwriting discounts and offering-related transaction costs. Sales Agreement In November 2019, the Company entered into a sales agreement (“Sales Agreement”) with Cowen and Company, LLC (“Cowen”), as sales agent, pursuant to which the Company may, from time to time, issue and sell at its option, shares of the Company’s common stock for an aggregate offering price of up to $50.0 million under an at-the-market offering (“ATM Offering”). Sales of the common stock, if any, will be made pursuant to a shelf registration statement that was declared effective by the Securities and Exchange Commission (“SEC”) on December 2, 2019. Cowen is acting as sole sales agent for any sales made under the Sales Agreement and the Company will pay Cowen a commission of up to 3% of the gross proceeds. The Company’s common stock will be sold at prevailing market prices at the time of the sale, and, as a result, prices may vary. The Company is not obligated to make any sales of shares of common stock under the Sales Agreement. Unless otherwise terminated earlier, the Sales Agreement continues until all shares available under the Sales Agreement have been sold. As of March 31, 2021, 1,553,299 shares have been sold under the Sales Agreement. During the fiscal year ended December 31, 2020, 217,403 shares were sold at an average price of $4.94, for net proceeds of $1.0 million and during the three months ended March 31, 2021, 1,335,896 shares were sold at an average price of $5.57, for net proceeds of $7.2 million. Shares Reserved for Future Issuance Shares of the Company’s common stock reserved for future issuance are as follows: March 31, 2021 December 31, 2020 Common stock awards issued and outstanding 7,509,223 7,172,029 Authorized for future issuance under 2014 Equity Incentive Plan 3,439,904 3,518,414 Authorized for future issuance under 2016 Inducement Plan 985,170 469,419 Employee stock purchase plan 1,306,730 1,018,060 Total 13,241,027 12,177,922

STOCK-BASED COMPENSATION

STOCK-BASED COMPENSATION	3 Months Ended
	Mar. 31, 2021
Share-based Payment Arrangement [Abstract]
STOCK-BASED COMPENSATION	STOCK-BASED COMPENSATION Stock Compensation Plans In January 2021, the common stock available for issuance under the 2014 Equity Incentive Plan (the “2014 Plan”) automatically increased by 4% of the total number of shares of the Company’s capital stock outstanding on December 31, 2020, or 1,154,678 shares. In February 2021, the Company’s board of directors approved an amendment to the 2016 Inducement Plan (the “Inducement Plan”) to increase the number of shares available for issuance by an additional 450,000. Employee Stock Purchase Plan In January 2021, the common stock available for issuance under the 2014 Employee Stock Purchase Plan (the “ESPP”) automatically increased by 1% of the total number of shares of the Company’s capital stock outstanding on December 31, 2020, or 288,670 shares. Stock-Based Compensation Expense The following table reflects stock-based compensation expense recognized for the three months ended March 31, 2021 and 2020 (in thousands): Three Months Ended March 31, 2021 2020 Research and development $ 107 $ 86 Selling, general and administrative 1,632 1,395 Total stock-based compensation expense $ 1,739 $ 1,481 Stock-based compensation of $38,000 was capitalized into inventory for the three months ended March 31, 2021, and $108,000 for the three months ended March 31, 2020. Stock-based compensation capitalized into inventory is recognized as cost of product sales when the related product is sold.

NET LOSS PER SHARE

NET LOSS PER SHARE	3 Months Ended
	Mar. 31, 2021
Earnings Per Share [Abstract]
NET LOSS PER SHARE	NET LOSS PER SHARE For all periods presented, there is no difference in the number of shares used to compute basic and diluted shares outstanding due to the Company’s net loss position. The following total outstanding shares of potentially dilutive securities were excluded from the computation of diluted net loss per share for the periods presented, because including them would have been anti-dilutive (in thousands): Three Months Ended March 31, 2021 2020 Options to purchase common stock 5,028 5,789 Restricted stock units 2,481 1,664 Total 7,509 7,453

BASIS OF PRESENTATION AND SUM_2

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. The unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) for interim financial information and with instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, these financial statements do not include all of the information and footnotes required by U.S. GAAP for complete financial statements. In the opinion of management, these financial statements include all adjustments (consisting only of normal recurring adjustments) considered necessary for a fair statement of the Company’s condensed consolidated financial statements for the periods presented. The condensed consolidated balance sheet at December 31, 2020 was derived from the audited consolidated financial statements, but does not include all disclosures required by U.S. GAAP. These interim financial results are not necessarily indicative of results to be expected for the full fiscal year ending December 31, 2021, or any other future period. Readers should read these interim unaudited condensed consolidated financial statements in conjunction with the audited consolidated financial statements and the related notes thereto for the year ended December 31, 2020, included in the Company’s Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission, or SEC. The Company’s significant accounting policies are detailed in its Annual Report on Form 10-K for the year ended December 31, 2020. During the three months ended March 31, 2021, other than the business combinations and intangible assets policies described below, the Company’s significant accounting policies have not changed materially from December 31, 2020.
Use of Estimates	Use of Estimates The preparation of the accompanying condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities and the reported amounts of revenues and expenses in the condensed consolidated financial statements and the accompanying notes. On an ongoing basis, management evaluates its estimates, including those related to revenue recognition and variable consideration, lease assets and liabilities, clinical trial
Risks and Uncertainties	Risks and Uncertainties Despite the roll-out of vaccines, the outbreak of the novel Coronavirus (“COVID-19”) is continuing both within the U.S. and globally. The Company is subject to risks and uncertainties as a result of the outbreak of COVID-19. Despite disruptions to the Company’s business operations, the COVID-19 pandemic did not significantly impact GOCOVRI prescription refill rates for the three months ended March 31, 2021, and thus far management has observed no disruptions to its inventory on hand or planned manufacturing schedule. However, new prescription rates have been impacted due to several factors, including: a fluid environment in which office practices are changing frequently including many healthcare providers have temporarily closed their offices or are restricting patient visits; patients are postponing visits to healthcare provider facilities; and the sales force continues to operate in a mix of virtual and live interactions with healthcare providers, adapting to the local environment. While management believes this initial decline and continued impact on new prescriptions to be temporary, the duration and severity is dependent on future developments, including new information that may emerge concerning the actions taken to contain or prevent further spread, all of which are highly uncertain and cannot be predicted with confidence.
Liquidity	Liquidity Since January 1, 2019, the Company has funded its operations primarily through sales of GOCOVRI, through sales of its common stock, and to a lesser extent through royalties received on net sales of NAMZARIC and sales of OSMOLEX ER. The Company made GOCOVRI available for physician and patient use in the fourth quarter of 2017, with a full commercial launch in January 2018. Prior to the generation of revenue from GOCOVRI, the Company had not generated any commercial revenue from the sale of its products. In November 2019, the Company entered into a sales agreement with Cowen and Company, LLC, pursuant to which it may, from time to time, issue and sell shares of common stock having an aggregate offering value of up to $50.0 million. As of March 31, 2021, the Company had issued 1,553,299 shares of common stock and raised net proceeds of $8.3 million under the sales agreement. In March 2021, the Company completed a follow-on public offering of 14,375,000 shares of common stock, which includes the exercise in full by the underwriters of their option to purchase 1,875,000 shares of common stock, at an offering price of $4.40 per share. Proceeds from the follow-on public offering were approximately $59.3 million, net of underwriting discounts and offering-related transaction costs. As of March 31, 2021, the Company had $127.4 million of cash, cash equivalents, and investments, which management believes will be sufficient to fund its projected operating requirements for at least 12 months from the issuance of these condensed consolidated financial statements. However, it is possible that the Company will not achieve the progress it expects, because revenues from GOCOVRI may be less than anticipated, especially in light of the current COVID-19 pandemic.
Business Combinations	Business Combinations The Company accounts for business combinations using the acquisition method of accounting, pursuant to ASC Topic 805. This method requires, among other things, that results of operations of acquired companies are included in the Company’s financial results beginning on the respective acquisition date, and that assets acquired and liabilities assumed are recognized separately at their fair value as of the acquisition date. Any excess of the fair value of consideration transferred (the “Purchase Price”) over the fair values of the net assets acquired is recognized as goodwill. The determination of estimated fair value requires the use of significant estimates and assumptions. The fair value of assets acquired and liabilities assumed may be subject to adjustment within the measurement period, which may be up to 12 months from the acquisition date. Transaction costs associated with business combinations are expensed when incurred.
Intangible Assets	Intangible Assets Intangible assets acquired in a business combination are stated at initial fair value less accumulated
Recent Accounting Pronouncements	Recent Accounting Pronouncements Accounting Pronouncements Adopted in 2021 In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740)—Simplifying the Accounting for Income Taxes . ASU 2019-12 removes certain exceptions to the general principles in Topic 740 and amends existing guidance to improve consistent application. This guidance became effective for the Company on January 1, 2021, and did not have a material impact on its condensed consolidated financial statements. New Accounting Pronouncements Not Yet Adopted In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses of Financial Instruments; in November 2018 the FASB issued a subsequent amendment ASU No. 2018-19, Codification Improvements to Topic 326, Financial Instruments—Credit Losses ; in April 2019 the FASB issued ASU No. 2019-04, Codification Improvements to Topic 326, Financial Instruments—Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments ; in May 2019 the FASB issued ASU No. 2019-05, Financial Instruments—Credit Losses (Topic 326): Targeted Transition Relief ; and in November 2019 the FASB issued ASU No. 2019-11, Codification Improvements to Topic 326, Financial Instruments—Credit Losses . The new guidance changes the methodology for measuring credit losses on financial instruments and the timing of when such losses are recorded. In November 2019 the FASB issued ASU No. 2019-10, Financial Instruments—Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842)—Effective Dates , which defers the effective date of ASU 2016-13 for all entities except SEC reporting companies that are not smaller reporting companies. As a smaller reporting company, this guidance is effective for fiscal years beginning after December 15, 2022. Early adoption is permitted. The Company is currently evaluating the timing and effect the new guidance will have on its consolidated financial statements.

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Schedule of fair value hierarchy for the Company’s financial assets and liabilities which require fair value measurement on a recurring basis	The following table represents the fair value hierarchy for the Company’s financial assets and liabilities which require fair value measurement on a recurring basis (in thousands): March 31, 2021 Total Level 1 Level 2 Level 3 Assets: Money market $ 116,718 $ 116,718 $ — $ — Corporate debt 2,605 — 2,605 — Total assets measured at fair value $ 119,323 $ 116,718 $ 2,605 $ — Liabilities: Embedded derivative liability $ 2,011 $ — $ — $ 2,011 Total liabilities measured at fair value $ 2,011 $ — $ — $ 2,011 December 31, 2020 Total Level 1 Level 2 Level 3 Assets: Money market $ 48,152 $ 48,152 $ — $ — Corporate debt 6,706 — 6,706 — U.S. Treasury securities 4,999 — 4,999 — Total assets measured at fair value $ 59,857 $ 48,152 $ 11,705 $ — Liabilities: Embedded derivative liability $ 2,378 $ — $ — $ 2,378 Total liabilities measured at fair value $ 2,378 $ — $ — $ 2,378
Summary of the changes in the estimated fair value of the Company’s embedded derivative	The following table sets forth changes in Level 3 liabilities measured at fair value on a recurring basis for the three months ended March 31, 2021 and 2020 (in thousands): Three Months Ended March 31, 2021 2020 Beginning balance $ 2,378 $ 2,157 Change in fair value included in interest and other income, net (367) 341 Ending balance $ 2,011 $ 2,498

INVESTMENTS (Tables)

INVESTMENTS (Tables)	3 Months Ended
	Mar. 31, 2021
Investments, Debt and Equity Securities [Abstract]
Summary of amortized cost, unrealized gain and loss and the fair value of available-for-sale securities	The following table is a summary of amortized cost, unrealized gain and loss, and the fair value of available-for-sale securities as of March 31, 2021 and December 31, 2020 (in thousands): March 31, 2021 Amortized Cost Gross Unrealized Gross Unrealized Fair Value Investments: Corporate debt $ 2,606 $ — $ (1) $ 2,605 Total $ 2,606 $ — $ (1) $ 2,605 Reported as: Long-term investments $ 2,606 $ — $ (1) $ 2,605 Total $ 2,606 $ — $ (1) $ 2,605 December 31, 2020 Amortized Cost Gross Unrealized Gross Unrealized Fair Value Investments: Corporate debt $ 6,706 $ — $ — $ 6,706 U.S. Treasury securities 4,999 — — 4,999 Total $ 11,705 $ — $ — $ 11,705 Reported as: Short-term investments $ 11,705 $ — $ — $ 11,705 Total $ 11,705 $ — $ — $ 11,705

INVENTORY (Tables)

INVENTORY (Tables)	3 Months Ended
	Mar. 31, 2021
Inventory Disclosure [Abstract]
Schedule of inventory	Inventory consists of the following (in thousands): March 31, 2021 December 31, 2020 Raw materials $ 780 $ 795 Work-in-process 4,095 4,403 Finished goods 2,661 2,096 Total inventory $ 7,536 $ 7,294

INTANGIBLE ASSETS, NET (Tables)

INTANGIBLE ASSETS, NET (Tables)	3 Months Ended
	Mar. 31, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of intangible assets, net	Intangible assets, net, consist of the following (in thousands): March 31, 2021 December 31, 2020 Developed product $ 770 $ — Accumulated amortization (28) — Total intangible assets, net $ 742 $ —
Schedule of future amortization	Estimated amortization expense for the remainder of 2021 and for each of the five succeeding years ending December 31 will be as follows (in thousands): Year Amount 2021 (remainder) $ 82 2022 110 2023 110 2024 110 2025 110 2026 110 Thereafter 110 Total amortization expense $ 742

ACQUISITION OF OSMOLEX ER (Tabl

ACQUISITION OF OSMOLEX ER (Tables)	3 Months Ended
	Mar. 31, 2021
Business Combinations [Abstract]
Summary of fair values of assets acquired and liabilities assumed	The following table summarizes the allocation of the purchase price to the fair values of assets acquired and liabilities assumed as of the acquisition date (in thousands): January 4, 2021 Prepaid expenses and other current assets $ 757 Intangible assets - developed product 770 Accrued liabilities (200) Total fair value of assets acquired and liabilities assumed $ 1,327

LONG-TERM DEBT (Tables)

LONG-TERM DEBT (Tables)	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
Schedule of payment obligations under the Royalty-Backed Loan	Payment obligations under the Royalty-Backed Loan are as follows (in thousands): March 31, 2021 December 31, 2020 Total repayment obligation $ 200,000 $ 200,000 Less: Interest to be accreted in future periods (45,798) (49,230) Less: Payments made (24,463) (20,806) Carrying value of loans payable $ 129,739 $ 129,964 Less: Current portion of long-term debt (3,580) (3,657) Non-current portion of long-term debt $ 126,159 $ 126,307

STOCKHOLDERS_ EQUITY (Tables)

STOCKHOLDERS’ EQUITY (Tables)	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
Schedule of shares of Company's common stock reserved for future issuance	Shares of the Company’s common stock reserved for future issuance are as follows: March 31, 2021 December 31, 2020 Common stock awards issued and outstanding 7,509,223 7,172,029 Authorized for future issuance under 2014 Equity Incentive Plan 3,439,904 3,518,414 Authorized for future issuance under 2016 Inducement Plan 985,170 469,419 Employee stock purchase plan 1,306,730 1,018,060 Total 13,241,027 12,177,922

STOCK-BASED COMPENSATION (Table

STOCK-BASED COMPENSATION (Tables)	3 Months Ended
	Mar. 31, 2021
Share-based Payment Arrangement [Abstract]
Schedule of allocation of total stock-based compensation expense	The following table reflects stock-based compensation expense recognized for the three months ended March 31, 2021 and 2020 (in thousands): Three Months Ended March 31, 2021 2020 Research and development $ 107 $ 86 Selling, general and administrative 1,632 1,395 Total stock-based compensation expense $ 1,739 $ 1,481

NET LOSS PER SHARE (Tables)

NET LOSS PER SHARE (Tables)	3 Months Ended
	Mar. 31, 2021
Earnings Per Share [Abstract]
Schedule of outstanding shares of potentially dilutive securities excluded from the computation of diluted net loss per share of common stock, because including them would have been anti-dilutive	The following total outstanding shares of potentially dilutive securities were excluded from the computation of diluted net loss per share for the periods presented, because including them would have been anti-dilutive (in thousands): Three Months Ended March 31, 2021 2020 Options to purchase common stock 5,028 5,789 Restricted stock units 2,481 1,664 Total 7,509 7,453

DESCRIPTION OF BUSINESS (Detail

DESCRIPTION OF BUSINESS (Details)	3 Months Ended
	Mar. 31, 2021segment
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of operating segments	1

BASIS OF PRESENTATION AND SUM_3

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($)	1 Months Ended		3 Months Ended	12 Months Ended	17 Months Ended
	Mar. 31, 2021	Nov. 30, 2019	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2021
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Sale of shares under the sales agreement, net proceeds			$ 66,508,000
Sale of stock, number of shares issued in transaction (in shares)	14,375,000
Sale of stock, offering price (in dollars per share)	$ 4.40		$ 4.40		$ 4.40
Sale of stock, proceeds received on transaction	$ 59,300,000
Cash, cash equivalents, and investments	$ 127,400,000		$ 127,400,000		$ 127,400,000
Over-Allotment Option
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Sale of stock, number of shares issued in transaction (in shares)	1,875,000
Cowen
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Shares authorized under the sales agreement		$ 50,000,000
Sale of shares under the sales agreement (in shares)			1,335,896	217,403	1,553,299
Sale of shares under the sales agreement, net proceeds			$ 7,200,000	$ 1,000,000	$ 8,300,000
Sale of stock, offering price (in dollars per share)	$ 5.57		$ 5.57	$ 4.94	$ 5.57

FAIR VALUE MEASUREMENTS - Finan

FAIR VALUE MEASUREMENTS - Financial Assets and Liabilities Which Require Fair Value Measurement (Details) - Recurring basis - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Assets:
Total assets measured at fair value	$ 119,323	$ 59,857
Liabilities:
Total liabilities measured at fair value	2,011	2,378
Embedded derivative liability
Liabilities:
Total liabilities measured at fair value	2,011	2,378
Level 1
Assets:
Total assets measured at fair value	116,718	48,152
Liabilities:
Total liabilities measured at fair value	0	0
Level 1 | Embedded derivative liability
Liabilities:
Total liabilities measured at fair value	0	0
Level 2
Assets:
Total assets measured at fair value	2,605	11,705
Liabilities:
Total liabilities measured at fair value	0	0
Level 2 | Embedded derivative liability
Liabilities:
Total liabilities measured at fair value	0	0
Level 3
Assets:
Total assets measured at fair value	0	0
Liabilities:
Total liabilities measured at fair value	2,011	2,378
Level 3 | Embedded derivative liability
Liabilities:
Total liabilities measured at fair value	2,011	2,378
Money market
Assets:
Total assets measured at fair value	116,718	48,152
Money market | Level 1
Assets:
Total assets measured at fair value	116,718	48,152
Money market | Level 2
Assets:
Total assets measured at fair value	0	0
Money market | Level 3
Assets:
Total assets measured at fair value	0	0
Corporate debt
Assets:
Total assets measured at fair value	2,605	6,706
Corporate debt | Level 1
Assets:
Total assets measured at fair value	0	0
Corporate debt | Level 2
Assets:
Total assets measured at fair value	2,605	6,706
Corporate debt | Level 3
Assets:
Total assets measured at fair value	$ 0	0
U.S. Treasury securities
Assets:
Total assets measured at fair value		4,999
U.S. Treasury securities | Level 1
Assets:
Total assets measured at fair value		0
U.S. Treasury securities | Level 2
Assets:
Total assets measured at fair value		4,999
U.S. Treasury securities | Level 3
Assets:
Total assets measured at fair value		$ 0

FAIR VALUE MEASUREMENTS - Narra

FAIR VALUE MEASUREMENTS - Narrative (Details) - Level 3 - Embedded derivative liability	Mar. 31, 2021
Measurement Input, Discount Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.168
Measurement Input, Change In Control Probability
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.030

FAIR VALUE MEASUREMENTS - Chang

FAIR VALUE MEASUREMENTS - Changes in Estimated Fair Value of Embedded Derivative (Details) - Level 3 - Long-term debt with embedded derivative - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 2,378	$ 2,157
Change in fair value included in interest and other income, net	(367)	341
Ending balance	$ 2,011	$ 2,498

INVESTMENTS (Details)

INVESTMENTS (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Available-for-sale securities
Amortized cost	$ 2,606,000		$ 11,705,000
Gross unrealized gains	0		0
Gross unrealized losses	(1,000)		0
Fair value	2,605,000		11,705,000
Debt securities, available-for-sale, realized gain	0	$ 0
Debt securities, available-for-sale, realized loss	0	$ 0
Long-term investments
Available-for-sale securities
Amortized cost	2,606,000
Gross unrealized gains	0
Gross unrealized losses	(1,000)
Fair value	2,605,000
Accrued interest	$ 37,000
Long-term investments | Minimum
Available-for-sale securities
Maturity of long term investment	12 months
Long-term investments | Maximum
Available-for-sale securities
Maturity of long term investment	24 months
Short-term investments
Available-for-sale securities
Amortized cost			11,705,000
Gross unrealized gains			0
Gross unrealized losses			0
Fair value			11,705,000
Accrued interest			100,000
Corporate debt
Available-for-sale securities
Amortized cost	$ 2,606,000		6,706,000
Gross unrealized gains	0		0
Gross unrealized losses	(1,000)		0
Fair value	$ 2,605,000		6,706,000
U.S. Treasury securities
Available-for-sale securities
Amortized cost			4,999,000
Gross unrealized gains			0
Gross unrealized losses			0
Fair value			$ 4,999,000

INVENTORY (Details)

INVENTORY (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Inventory Disclosure [Abstract]
Provision for write-down of inventory	$ 0	$ 289
Raw materials	780		$ 795
Work-in-process	4,095		4,403
Finished goods	2,661		2,096
Total inventory	$ 7,536		$ 7,294

INTANGIBLE ASSETS, NET - Narrat

INTANGIBLE ASSETS, NET - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Useful life	7 years
Amortization of intangible assets	$ 28	$ 0

INTANGIBLE ASSETS, NET - Schedu

INTANGIBLE ASSETS, NET - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Developed product	$ 770	$ 0
Accumulated amortization	(28)	0
Total intangible assets, net	$ 742	$ 0

INTANGIBLE ASSETS, NET - Future

INTANGIBLE ASSETS, NET - Future Amortization (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
2021 (remainder)	$ 82
2022	110
2023	110
2024	110
2025	110
2026	110
Thereafter	110
Total intangible assets, net	$ 742	$ 0

LICENSE AGREEMENTS (Details)

LICENSE AGREEMENTS (Details) - USD ($)	1 Months Ended	3 Months Ended
	Nov. 30, 2012	Mar. 31, 2021	Mar. 31, 2020
License Agreements
Revenues		$ 19,311,000	$ 14,481,000
Period describing the commercial launch of dose		15 years
Royalty
License Agreements
Revenues		$ 1,333,000	0
License agreement
License Agreements
Upfront payment received	$ 65,000,000
Maximum total additional cash payments receivable upon achievement of certain development and regulatory milestones	$ 95,000,000
Prosecution and litigation cost		$ 0	$ 0

ACQUISITION OF OSMOLEX ER - Nar

ACQUISITION OF OSMOLEX ER - Narrative (Details) - USD ($) $ in Thousands	Jan. 04, 2021	Dec. 01, 2020	Mar. 31, 2021	Mar. 31, 2021	Mar. 31, 2020
Business Acquisition [Line Items]
Compensation expense			$ 1,739		$ 1,481
Amortization of intangible assets			28		$ 0
OSMOLEX ER
Business Acquisition [Line Items]
Asset purchase agreement, noncompete agreement, period		5 years
Payments to acquire businesses, gross	$ 7,300
Base purchase price	7,500
Liabilities incurred	200
Prosecution and litigation cost	5,200
Compensation expense	800
Acquisition-related expenses	$ 1,300
Net product sales since acquisition				$ 300
OSMOLEX ER | Patents
Business Acquisition [Line Items]
Amortization of intangible assets			$ 200

ACQUISITION OF OSMOLEX ER - Sum

ACQUISITION OF OSMOLEX ER - Summary of Fair Values of Assets Acquired and Liabilities Assumed (Details) - OSMOLEX ER $ in Thousands	Jan. 04, 2021USD ($)
Business Acquisition [Line Items]
Prepaid expenses and other current assets	$ 757
Intangible assets - developed product	770
Accrued liabilities	(200)
Total fair value of assets acquired and liabilities assumed	$ 1,327

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Details) $ in Millions	Oct. 29, 2020USD ($)	Mar. 31, 2021USD ($)claim
Loss Contingencies [Line Items]
Number of legal claims | claim		0
Qui Tam Complaint | Pending Litigation | Unfavorable Regulatory Action
Loss Contingencies [Line Items]
Claim for damages (potentially more than)		$ 2,500
Putative Class Action Lawsuit | Pending Litigation
Loss Contingencies [Line Items]
Litigation settlement, amount awarded to other party	$ 7.5

LONG-TERM DEBT - Narrative (Det

LONG-TERM DEBT - Narrative (Details) - USD ($)	Apr. 29, 2020	Apr. 15, 2020	May 31, 2017	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2017
Debt Instrument [Line Items]
Proceeds from PPP Loan		$ 2,700,000
Repayments of PPP loan	$ 2,700,000
HCRP | Royalty-backed loan agreement
Debt Instrument [Line Items]
Proceeds from issuance of debt			$ 35,000,000			$ 65,000,000
Percentage revenue interest of future net sales			12.50%
Quarterly royalty payment (up to)			$ 15,000,000
Royalty percentage of future net sales			6.25%
Royalty trail cap, percentage of face amount			200.00%
Voluntary prepay election, amount due, percentage of funded amount			200.00%
Interest rate, stated percentage			11.00%
Contingent consideration, asset						$ 65,000,000
Unpaid interest payment added to principal amount, term			2 years 3 months
Lender expense			$ 400,000
Payment of debt issuance costs			800,000
Interest expense				$ 3,400,000	$ 3,600,000
Effective interest rate				13.00%
HCRP | Royalty-backed loan agreement | Level 3
Debt Instrument [Line Items]
Long-term debt, fair value				$ 113,200,000
HCRP | Royalty-backed loan agreement | Prior to December 31, 2022
Debt Instrument [Line Items]
Covenant, prepayment provisions, change in control, required cumulative payments			175,000,000
HCRP | Royalty-backed loan agreement | Subsequent to December 31, 2022
Debt Instrument [Line Items]
Covenant, prepayment provisions, change in control, required cumulative payments			$ 195,000,000
Royalty percentage of future net sales if principal and interest payments below minimum specified levels (up to)			22.50%

LONG-TERM DEBT - Long-term Debt

LONG-TERM DEBT - Long-term Debt and Unamortized Debt Discount Balances (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Less: Current portion of long-term debt	$ (3,580)	$ (3,657)
Non-current portion of long-term debt	126,159	126,307
HCRP | Royalty-backed loan agreement
Debt Instrument [Line Items]
Total repayment obligation	200,000	200,000
Less: Interest to be accreted in future periods	(45,798)	(49,230)
Less: Payments made	(24,463)	(20,806)
Carrying value of loans payable	129,739	129,964
Less: Current portion of long-term debt	(3,580)	(3,657)
Non-current portion of long-term debt	$ 126,159	$ 126,307

STOCKHOLDERS_ EQUITY (Details)

STOCKHOLDERS’ EQUITY (Details)	1 Months Ended	3 Months Ended	12 Months Ended	17 Months Ended
	Mar. 31, 2021USD ($)vote$ / sharesshares	Mar. 31, 2021USD ($)vote$ / sharesshares	Dec. 31, 2020USD ($)$ / sharesshares	Mar. 31, 2021USD ($)vote$ / sharesshares	Nov. 30, 2019USD ($)
Shareholders' Equity
Authorized shares of common stock (in shares)	100,000,000	100,000,000	100,000,000	100,000,000
Dividends declared | $		$ 0
Common stock votes per share | vote	1	1		1
Sale of stock, number of shares issued in transaction (in shares)	14,375,000
Sale of stock, offering price (in dollars per share) | $ / shares	$ 4.40	$ 4.40		$ 4.40
Sale of stock, proceeds received on transaction | $	$ 59,300,000
Issuance of common stock in conjunction with equity offerings, net of commissions and issuance costs | $		$ 66,508,000
Total common stock reserved for future issuance (in shares)	13,241,027	13,241,027	12,177,922	13,241,027
Over-Allotment Option
Shareholders' Equity
Sale of stock, number of shares issued in transaction (in shares)	1,875,000
Cowen
Shareholders' Equity
Sale of stock, offering price (in dollars per share) | $ / shares	$ 5.57	$ 5.57	$ 4.94	$ 5.57
At-the-market offering, aggregate offering price (up to) | $					$ 50,000,000
At-the-market offering, commission as a percentage of gross proceeds (up to)					3.00%
Sale of shares under the sales agreement (in shares)		1,335,896	217,403	1,553,299
Issuance of common stock in conjunction with equity offerings, net of commissions and issuance costs | $		$ 7,200,000	$ 1,000,000	$ 8,300,000
Stock Options
Shareholders' Equity
Total common stock reserved for future issuance (in shares)	7,509,223	7,509,223	7,172,029	7,509,223
Stock Options | 2014 Equity Incentive Plan
Shareholders' Equity
Authorized for future issuance (in shares)	3,439,904	3,439,904	3,518,414	3,439,904
Stock Options | 2016 Inducement Plan
Shareholders' Equity
Authorized for future issuance (in shares)	985,170	985,170	469,419	985,170
Employee Stock | Employee stock purchase plan
Shareholders' Equity
Total common stock reserved for future issuance (in shares)	1,306,730	1,306,730	1,018,060	1,306,730

STOCK-BASED COMPENSATION - Narr

STOCK-BASED COMPENSATION - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended
	Feb. 28, 2021	Jan. 31, 2021	Mar. 31, 2021	Mar. 31, 2020
Stock Option Plans
Stock-based compensation capitalized in inventory			$ 38	$ 108
2014 Equity Incentive Plan
Stock Option Plans
Increase in common stock reserved for issuance as a percentage of total number of shares of the Company's capital stock outstanding on the last day of the preceding fiscal year		4.00%
Increase in common stock available for issuance (in shares)		1,154,678
2016 Inducement Plan
Stock Option Plans
Company’s additional common stock available for issuance (in shares)	450,000
Employee stock purchase plan
Stock Option Plans
Increase in common stock reserved for issuance as a percentage of total number of shares of the Company's capital stock outstanding on the last day of the preceding fiscal year		1.00%
Increase in common stock available for issuance (in shares)		288,670

STOCK-BASED COMPENSATION - Inco

STOCK-BASED COMPENSATION - Income Statement Location (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Stock-based compensation expense
Stock-based compensation expense	$ 1,739	$ 1,481
Research and development
Stock-based compensation expense
Stock-based compensation expense	107	86
Selling, general and administrative
Stock-based compensation expense
Stock-based compensation expense	$ 1,632	$ 1,395

NET LOSS PER SHARE (Details)

NET LOSS PER SHARE (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (in shares)	7,509	7,453
Options to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (in shares)	5,028	5,789
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (in shares)	2,481	1,664