Zevra Therapeutics (ZVRA) 10-K 28 Feb 20 2019 FY Annual report Financial data

Document And Entity Information

Document And Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2019	Feb. 26, 2020	Jun. 28, 2019
Document Information [Line Items]
Entity Registrant Name	KEMPHARM, INC
Entity Central Index Key	0001434647
Trading Symbol	kmph
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	No
Entity Emerging Growth Company	true
Entity Ex Transition Period	true
Entity Small Business	true
Entity Interactive Data Current	Yes
Entity Common Stock, Shares Outstanding (in shares)		50,684,743
Entity Public Float			$ 38,659,464
Entity Shell Company	false
Document Type	10-K
Document Period End Date	Dec. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Amendment Flag	false
Title of 12(b) Security	Common Stock, $0.0001 par value

Balance Sheets

Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Assets
Cash and cash equivalents	$ 3,217	$ 18,409
Marketable securities		3,260
Accounts and other receivables	1,865	140
Prepaid expenses and other current assets	1,552	1,912
Total current assets	6,634	23,721
Property and equipment, net	1,471	1,753
Operating lease right-of-use assets	1,537
Restricted cash	338	710
Other long-term assets	527	562
Total assets	10,507	26,746
Liabilities and stockholders’ deficit
Accounts payable and accrued expenses	4,911	8,342
Current portion of convertible notes		3,333
Current portion of capital lease obligation		214
Current portion of operating lease liabilities	284
Other current liabilities	236	115
Total current liabilities	5,431	12,004
Convertible notes, less current portion, net	77,343	78,105
Derivative and warrant liability	120	2,118
Capital lease obligation, less current portion		396
Operating lease liabilities, less current portion	1,901
Other long-term liabilities	168	689
Total liabilities	84,963	93,312
Commitments and contingencies (Note H)
Stockholders' deficit:
Common stock, $0.0001 par value, 250,000,000 shares authorized, 36,350,785 shares issued and outstanding as of December 31, 2019; 26,455,352 shares issued and outstanding as of December 31, 2018	4	3
Additional paid-in capital	171,254	154,623
Accumulated deficit	(245,714)	(221,192)
Total stockholders' deficit	(74,456)	(66,566)
Total liabilities and stockholders' deficit	10,507	26,746
Series A Convertible Preferred Stock [Member]
Stockholders' deficit:
Preferred stock
Series B-1 Convertible Preferred Stock [Member]
Stockholders' deficit:
Preferred stock
Series B-2 Convertible Preferred Stock [Member]
Stockholders' deficit:
Preferred stock
Undesignated Preferred Stock [Member]
Stockholders' deficit:
Preferred stock

Balance Sheets (Parentheticals)

Balance Sheets (Parentheticals) - $ / shares	Dec. 31, 2019	Dec. 31, 2018
Preferred stock, shares authorized (in shares)	10,000,000
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	250,000,000	250,000,000
Common stock, shares issued (in shares)	36,350,785	26,455,352
Common stock, shares outstanding (in shares)	36,350,785	26,455,352
Series A Convertible Preferred Stock [Member]
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	9,578	9,578
Preferred stock, shares issued (in shares)	9,577	9,577
Preferred stock, shares outstanding (in shares)	0	0
Series B-1 Convertible Preferred Stock [Member]
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	1,576	0
Preferred stock, shares issued (in shares)	1,576	0
Preferred stock, shares outstanding (in shares)	0	0
Series B-2 Convertible Preferred Stock [Member]
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	27,000	0
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Undesignated Preferred Stock [Member]
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	9,961,846	9,990,422
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0

Statements of Operations

Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Revenue	$ 12,839	$ 0
Operating expenses:
Royalty and direct contract acquisition costs	2,945
Research and development	19,415	41,759
General and administrative	10,816	12,508
Severance expense		1,636
Total operating expenses	33,176	55,903
Loss from operations	(20,337)	(55,903)
Other (expense) income:
Gain on extinguishment of debt		2
Interest expense related to amortization of debt issuance costs and discount	(1,656)	(1,618)
Interest expense on principal	(4,858)	(5,469)
Fair value adjustment related to derivative and warrant liability	1,998	5,976
Interest and other income, net	309	420
Total other (expense) income	(4,207)	(689)
Loss before income taxes	(24,544)	(56,592)
Income tax benefit	22	126
Net loss	$ (24,522)	$ (56,466)
Net loss per share of common stock:
Basic and diluted (in dollars per share)	$ (0.83)	$ (3.15)
Weighted average number of shares of common stock outstanding:
Basic and diluted (in shares)	29,654,968	17,930,023

Statements of Changes in Stockh

Statements of Changes in Stockholders' Deficit - USD ($) $ in Thousands	ATM Agreement Sales [Member]Preferred Stock [Member]Series A Convertible Preferred Stock [Member]	ATM Agreement Sales [Member]Preferred Stock [Member]Series B-1 Convertible Preferred Stock [Member]	ATM Agreement Sales [Member]Preferred Stock [Member]Series B-2 Convertible Preferred Stock [Member]	ATM Agreement Sales [Member]Undesignated Preferred Stock [Member]	ATM Agreement Sales [Member]Common Stock [Member]	ATM Agreement Sales [Member]Additional Paid-in Capital [Member]	ATM Agreement Sales [Member]Retained Earnings [Member]	ATM Agreement Sales [Member]	Deerfield Convertible Notes [Member]Preferred Stock [Member]Series A Convertible Preferred Stock [Member]	Deerfield Convertible Notes [Member]Preferred Stock [Member]Series B-1 Convertible Preferred Stock [Member]	Deerfield Convertible Notes [Member]Preferred Stock [Member]Series B-2 Convertible Preferred Stock [Member]	Deerfield Convertible Notes [Member]Undesignated Preferred Stock [Member]	Deerfield Convertible Notes [Member]Common Stock [Member]	Deerfield Convertible Notes [Member]Additional Paid-in Capital [Member]	Deerfield Convertible Notes [Member]Retained Earnings [Member]	Deerfield Convertible Notes [Member]	Underwriting Public Offering [Member]Preferred Stock [Member]Series A Convertible Preferred Stock [Member]	Underwriting Public Offering [Member]Preferred Stock [Member]Series B-1 Convertible Preferred Stock [Member]	Underwriting Public Offering [Member]Preferred Stock [Member]Series B-2 Convertible Preferred Stock [Member]	Underwriting Public Offering [Member]Undesignated Preferred Stock [Member]	Underwriting Public Offering [Member]Common Stock [Member]	Underwriting Public Offering [Member]Additional Paid-in Capital [Member]	Underwriting Public Offering [Member]Retained Earnings [Member]	Underwriting Public Offering [Member]	Equity Line of Credit [Member]Preferred Stock [Member]Series A Convertible Preferred Stock [Member]	Equity Line of Credit [Member]Preferred Stock [Member]Series B-1 Convertible Preferred Stock [Member]	Equity Line of Credit [Member]Preferred Stock [Member]Series B-2 Convertible Preferred Stock [Member]	Equity Line of Credit [Member]Undesignated Preferred Stock [Member]	Equity Line of Credit [Member]Common Stock [Member]	Equity Line of Credit [Member]Additional Paid-in Capital [Member]	Equity Line of Credit [Member]Retained Earnings [Member]	Equity Line of Credit [Member]	Optional Exchange Principal Amount [Member]Preferred Stock [Member]Series A Convertible Preferred Stock [Member]	Optional Exchange Principal Amount [Member]Preferred Stock [Member]Series B-1 Convertible Preferred Stock [Member]	Optional Exchange Principal Amount [Member]Preferred Stock [Member]Series B-2 Convertible Preferred Stock [Member]	Optional Exchange Principal Amount [Member]Undesignated Preferred Stock [Member]	Optional Exchange Principal Amount [Member]Common Stock [Member]	Optional Exchange Principal Amount [Member]Additional Paid-in Capital [Member]	Optional Exchange Principal Amount [Member]Retained Earnings [Member]	Optional Exchange Principal Amount [Member]	Convertible Notes 2021 [Member]Preferred Stock [Member]Series A Convertible Preferred Stock [Member]	Convertible Notes 2021 [Member]Preferred Stock [Member]Series B-1 Convertible Preferred Stock [Member]	Convertible Notes 2021 [Member]Preferred Stock [Member]Series B-2 Convertible Preferred Stock [Member]	Convertible Notes 2021 [Member]Undesignated Preferred Stock [Member]	Convertible Notes 2021 [Member]Common Stock [Member]	Convertible Notes 2021 [Member]Additional Paid-in Capital [Member]	Convertible Notes 2021 [Member]Retained Earnings [Member]	Convertible Notes 2021 [Member]	Preferred Stock [Member]Series A Convertible Preferred Stock [Member]	Preferred Stock [Member]Series B-1 Convertible Preferred Stock [Member]	Preferred Stock [Member]Series B-2 Convertible Preferred Stock [Member]	Undesignated Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Total
Balance at Dec. 31, 2017																																																					$ 1	$ 107,209	$ (164,726)	$ (57,516)
Net loss																																																							(56,466)	(56,466)
Stock-based compensation expense																																																						6,495		6,495
Issuance of common stock					$ 1	$ 4,827		$ 4,828													$ 1	$ 23,499		$ 23,500
Offering expenses charged to equity																																																						(554)		(554)
Conversion of principal and interest on Deerfield Convertible Note														$ 3,502		$ 3,502																														$ 9,577		$ 9,577
Exercise of stock options																																																						68		68
Balance at Dec. 31, 2018																																																					3	154,623	(221,192)	(66,566)
Net loss																																																							(24,522)	(24,522)
Stock-based compensation expense																																																						4,410		4,410
Issuance of common stock																														$ 5,446		$ 5,446					$ 1	$ 1,199		$ 1,200
Offering expenses charged to equity																																																						(151)		(151)
Conversion of principal and interest on Deerfield Convertible Note																																														$ 3,000		$ 3,000
Change in fair value of embedded conversion feature in connection with debt modification																																																						2,311		2,311
Deferred offering costs																														$ 300		$ 300																						116		116
Balance at Dec. 31, 2019																																																					$ 4	$ 171,254	$ (245,714)	$ (74,456)

Statements of Cash Flows

Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Cash flows from operating activities:
Net loss	$ (24,522,000)	$ (56,466,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Gain on extinguishment of debt		(2,000)
Stock-based compensation expense	4,410,000	6,495,000
Non-cash interest expense	1,417,000	2,089,000
Amortization of debt issuance costs and debt discount	1,656,000	1,618,000
Depreciation and amortization expense	304,000	324,000
Fair value adjustment related to derivative and warrant liability	(1,998,000)	(5,976,000)
Write-off of deferred offering costs	116,000
Change in assets and liabilities:
Accounts and other receivables	(1,725,000)
Prepaid expenses and other assets	544,000	(548,000)
Operating lease right-of-use assets	(1,537,000)
Accounts payable and accrued expenses	(3,789,000)	(1,635,000)
Operating lease liabilities	2,185,000
Other liabilities	(798,000)	(102,000)
Net cash used in operating activities	(23,737,000)	(54,203,000)
Cash flows from investing activities:
Purchases of property and equipment	(26,000)	(21,000)
Maturities and sales of marketable securities	3,260,000	33,353,000
Net cash provided by investing activities	3,234,000	33,332,000
Cash flows from financing activities:
Proceeds from equity line of credit	5,446,000
Proceeds from at-the-market offering, net of commissions		4,828,000
Proceeds from underwritten public offering, net of commissions		23,500,000
Repayment of obligations under capital lease		(193,000)
Payment of deferred offering costs		(184,000)
Repayment of principal on finance lease liabilities	(207,000)
Payment of debt issuance costs	(300,000)
Proceeds from exercise of common stock options		68,000
Net cash provided by financing activities	4,939,000	28,019,000
Net (decrease) increase in cash, cash equivalents and restricted cash	(15,564,000)	7,148,000
Cash, cash equivalents and restricted cash, beginning of year	19,119,000	11,971,000
Cash, cash equivalents and restricted cash, end of year	3,555,000	19,119,000
Supplemental cash flow information:
Cash paid for interest	5,362,000	5,539,000
Commitment shares issued in connection with equity line of credit included in deferred offering costs	300,000
Deferred offering costs included in accounts payable and accrued expenses		181,000
Property and equipment financed under a lease agreement		52,000
Property and equipment included in accounts payable and accrued expenses	4,000
Conversion from Deerfield Convertible Note to Common Stock [Member]
Supplemental cash flow information:
Deerfield Convertible Note principal and interest converted to common stock		3,502,000
The 2021 Notes Converted to Preferred Stock [Member]
Supplemental cash flow information:
2021 Notes principal converted to preferred stock	1,537,000	9,577,000
The 2021 Notes Converted to Common Stock [Member]
Supplemental cash flow information:
2021 Notes principal converted to preferred stock	1,463,000
The 2019 Notes Converted to Common Stock [Member]
Supplemental cash flow information:
2021 Notes principal converted to preferred stock	$ 1,200,000

Note A - Description of Busines

Note A - Description of Business and Basis of Presentation	12 Months Ended
	Dec. 31, 2019
Notes to Financial Statements
Business Description and Basis of Presentation [Text Block]	A. Description of Business and Basis of Presentation Organization KemPharm, Inc. (the “Company”) is a specialty pharmaceutical company focused on the discovery and development of proprietary prodrugs to treat serious medical conditions through its proprietary Ligand Activated Therapy ("LAT™") technology. The Company utilizes its proprietary LAT technology to generate improved prodrug versions of U.S. Food and Drug Administration (the "FDA") approved drugs as well as to generate prodrug versions of existing compounds that may KP415 KP484, KP879. October 2006 May 2014. Going Concern The financial statements have been prepared on a going concern basis which assumes that the Company will be able to realize its assets and discharge its liabilities in the normal course of business for the foreseeable future. The Company has experienced recurring negative operating cash flows and has a stockholders' deficit, and its existing cash and cash equivalents and restricted cash are not one may may not Management believes these conditions raise substantial doubt about the Company’s ability to continue as a going concern within the twelve not first 2021. KP415 not not not third 2020. not Management intends to finance operating costs over the next twelve 3 $150.0 October 2019, 3 $80.0 no After the Company files this Annual Report on Form 10 December 31, 2019 ( I.B.6. 3, may twelve twelve I.B.6. may not one third 60 I.B.6. 3 $10.9 $4.0 $ 5.7 3 12 may December 31, 2019, 3,401,271 $5.4 Entry into First ATM Agreement In October 2016, September 2018. 762,338 $4.9 three 3.0% Entry into Second ATM Agreement In September 2018, may $50,000,000 3 October 17, 2016. 3 $50,000,000 March 2019, $3.2 I.B.6 3. February 2020, December 31, 2019, not Underwritten Public Offering In October 2018, October 10, 2018, 8,333,334 3, October 17, 2016, October 17, 2016 October 5, 2018, $3.00 $23.1 Entry into Prior Purchase Agreement In February 2019, $15.0 36 120,200 may 3 December 31, 2019, 3,401,271 $5.4 February 2020, Entry into APADAZ License Agreement In October 2018, Pursuant to the APADAZ License Agreement, KVK agreed to pay the Company certain payments and cost reimbursements of an estimated $3.4 $2.0 10 $53.0 30% 50% four The APADAZ License Agreement will terminate on the later of the date that all of the patent rights for APADAZ have expired in the United States or KVK’s cessation of commercialization of APADAZ in the United States. KVK may 90 third may 18 may six may 30 not The APADAZ License Agreement also established a joint steering committee, which monitors progress of the commercialization of APADAZ. Entry into KP415 In September 2019, “KP415 KP415 KP415, KP484, KP879, KP922 KP415 KP484, KP415 $10.0 $63.0 KP415 KP484; $420.0 KP415 KP415 KP415 Commave has also agreed to be responsible and reimburse the Company for all of development, commercialization and regulatory expenses for the Licensed Product Candidates, subject to certain limitations as set forth in the KP415 The KP415 KP415 KP484. KP415 KP484; In accordance with the terms of the Company’s March 20, 2012 10% KP415, KP484 KP879 KP415 Entry into Purchase Agreement In February 2020, may $4.0 12 308,637 may 3

Note B - Summary of Significant

Note B - Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2019
Notes to Financial Statements
Significant Accounting Policies [Text Block]	B. Summary of Significant Accounting Policies Use of Estimates The preparation of financial statements in conformity with U.S. generally accepted accounting principles ("GAAP") requires the Company to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates. On an ongoing basis, the Company evaluates its estimates and assumptions, including those related to revenue recognition, the useful lives of property and equipment, the recoverability of long-lived assets, the incremental borrowing rate for leases, and assumptions used for purposes of determining stock-based compensation, income taxes, and the fair value of the derivative and warrant liability, among others. The Company bases its estimates on historical experience and on various other assumptions that it believes to be reasonable, the results of which form the basis for making judgments about the carrying value of assets and liabilities. Reclassifications During 2019, $0.1 December 31, 2018 $0.1 December 31, 2018. no Concentration of Credit Risk Financial instruments that potentially expose the Company to concentrations of credit risk consist principally of cash on deposit with multiple financial institutions, the balances of which frequently exceed insured limits. Cash and Cash Equivalents The Company considers any highly liquid investm ents with an original maturity of three Marketable Securities and Long-term Investments The Company maintained investment securities that were classified as trading securities. These securities were carried at fair value with unreali zed gains and losses included in other (expense) income on the statements of operations. The securities primarily consisted of certificates of deposit, U.S. Treasury securities and U.S. government-sponsored agency securities. Property and Equipment The Company records property and equipment at cost less accumulated depreciation and amortization. Costs of renewals and improvements that extend the useful lives of the assets are capitalized. Maintenance and repairs are expensed as incurred. Depreciation is determined on a straight-line basis over the estimated useful lives of the assets, which generally range from three ten Debt Issuance Costs Debt issuance costs incurred in connection with financing arrangements are recorded as a reduction of the related debt on the balance sheet and amortiz ed over the life of the respective financing arrangement using the effective interest method. Supply Arrangements The Company enters into supply arrangements for the supply of components of its product and product candidates. These arrangements also may share of future revenue if related product or product candidates reach commercialization. Costs under these supply arrangements, if any, are expensed as incurred (Note I). Impairment of Long-Lived Assets Long-lived assets to be held and used are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amounts of the assets may not When such events occur, the Company compares the carrying amounts of the assets to their undiscounted expected future cash flows. If the undiscounted cash flows are insufficient to recover the carrying values, an impairment loss is recorded for the difference between the carrying values and fair values of the asset. No December 31, 2019 2018 . Fair Value of Financial Instruments Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date, based on the Company’s principal or, in absence of a principal, most advantageous market for the specific asset or liability. The Company uses a three equent to their initial measurement. The hierarchy requires the Company to use observable inputs when available, and to minimize the use of unobservable inputs, when determining fair value. The three ● Level 1 —Observable inputs that reflect quoted market prices (unadjusted) for identical assets or liabilities in active markets; ● Level 2 —Observable inputs other than quoted prices in active markets that are observable either directly or indirectly in the marketplace for identical or similar assets and liabilities; and ● Level 3 —Unobservable inputs that are supported by little or no Revenue Recognition The Company commenced recognizing revenue in accordance with the provisions of ASC 606, Revenue from Contracts with Customers 606” January 1, 2018. no Arrangements with Multiple-Performance Obligations From time to time, the Company enters into arrangements for research and development, manufacturing and/or commercialization services. Such arrangements may In arrangements involving more than one not The consideration allocated to each distinct performance obligation is recognized as revenue when control of the related goods or services is transferred. Consideration associated with at-risk substantive performance milestones is recognized as revenue when it is probable that a significant reversal of the cumulative revenue recognized will not Licensing Agreements The Company enters into licensing agreements with licensees that fall under the scope of ASC 606. The terms of the Company’s licensing agreements typically include one may As part of the accounting for these agreements, the Company must develop estimates and assumptions that require judgment to determine the underlying stand-alone selling price for each performance obligation which determines how the transaction price is allocated among the performance obligations. Generally, the estimation of the stand-alone selling price may Up-front Fees: Milestone Payments: not not not may KP415 In September 2019, KP415 KP415, KP484, KP879, KP922 KP415 In exchange for the exclusive, worldwide license, discussed above, Commave paid the Company a non-refundable upfront payment of $10.0 $63.0 KP415 KP484. $420.0 KP415 KP415 KP415 Commave also agreed to be responsible for and reimburse the Company for all of development, commercialization and regulatory expenses incurred on the licensed products, subject to certain limitations as set forth in the KP415 The KP415 606, not KP415 606, third two $10.0 KP415 The consideration allocated to the grant of the exclusive, worldwide license was $10.0 KP415 KP415 The consideration allocated to the performance of consulting services, which includes the reimbursement of out-of-pocket third KP415 third third no third third third third 606 third KP415 third KP415 KP415 December 31, 2019, 66% third Under the KP415 KP415 KP415 first not third 606 not not The Company is entitled to additional payments from Commave conditioned upon the achievement of specified regulatory milestones related to KP415 KP484 KP415 KP415 KP415 not not not For the year ended December 31, 2019, $12.8 $10.0 $1.1 third $1.7 December 31, 2019, $1.4 $0.2 third $10.0 KP415 10% third 2019. 340 40, $2.8 KP415 third December 31, 2019, $1.9 no December 31, 2018. no December 31, 2019 2018. Accounts and Other Receivables Accounts and other receivables consists of receivables under the KP415 KP415 third December 31, 2019 2018 no Research and Development Major components of research and development costs include cash compensation, stock-based compensation, depreciation and amortization expense on research and development property and equipment, costs of preclinical studies, clin ical trials and related clinical manufacturing, costs of drug development, costs of materials and supplies, facilities cost, overhead costs, regulatory and compliance costs, and fees paid to consultants and other entities that conduct certain research and development activities on the Company’s behalf. Costs incurred in research and development are expensed as incurred. The Company records nonrefundable advance payments it makes for future research and development activities as prepaid expenses. Prepaid expenses are recognized as expense in the statements of operations as the Company receives the related goods or services. The Company enters into contractual agreements with third pleted over an extended period of time. The Company records liabilities under these contractual commitments when an obligation has been incurred. This accrual process involves reviewing open contracts and purchase orders, communicating with the applicable personnel to identify services that have been performed and estimating the level of service performed and the associated cost when the Company has not Patent Costs Patent costs, including related legal costs, are expensed as incurred and recorded within general and administrative expenses on the statements of operations. Income Taxes The Company recognizes deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the financial reporting and tax basis of assets and liabilities, as well as for operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using the tax rates that are expected to apply to taxable income for the years in which those tax assets and liabilities are expected to be realized or settled. Valuation allowances are recorded to reduce deferred tax assets to the amount the Company believes is more likely than not Uncertain tax positions are recognized only when the Company believes it is more likely than not t the tax position will be upheld on examination by the taxing authorities based on the merits of the position. The Company recognizes interest and penalties, if any, related to unrecognized income tax uncertainties in income tax expense. The Company did not December 31, 2019 2018 The Company files income tax returns in the United States for federal and various state jurisdictions. With few exceptions, the Company is no 2014, 2014 may No Stock-Based Compensation The Company measures and recognizes compensation expense for all stock-based payment awards made to employees, officers an d directors based on the estimated fair values of the awards as of the grant date. The Company records the value of the portion of the award that is ultimately expected to vest as expense over the requisite service period. The Company also accounts for equity instruments issued to non-employees using a fair value approach under Accounting Standards Codification ("ASC") subtopic 505 50, 2018 07. Basic and Diluted Net Loss per Share of Common Stock The Company uses the two entitle the holders to participate in dividends and earnings of the Company. The two Segment and Geographic Information Operating segments are defined as components of an enterprise (business activity from which it earns revenue and incurs expenses) for which discrete financial information is ava ilable and regularly reviewed by the chief operating decision maker ("CODM") in deciding how to allocate resources and in assessing performance. The Company’s CODM is its Chief Executive Officer. The Company views its operations and manages its business as a single operating and reporting segment. All assets of the Company were held in the United States as of December 31, 2019 2018 Application of New or Revised Accounting Standards —Adopted From time to time, the Financial Accounting Standards Board (the “FASB”) or other standard-setting bodies issue accounting standards that are adopted by the Company as of the specified effective date. In April 2012, not In February 2016, 2016 02, Leases (Topic 842 ) 2016 02” January 1, 2019 not 12 not 2016 02 $ 2.6 January 1, 2019. In July 2017, 2017 11, Earnings Per Share (Topic 260 ), Distinguishing Liabilities from Equity (Topic 480 ), Derivatives and Hedging (Topic 815 ) – I. Accounting for Certain Financial Instruments with Down Round Features and II. Replacement of the Indefinite Deferral for Mandatorily Redeemable Financial Instruments of Certain Nonpublic Entities and Certain Mandatorily Redeemable Noncontrolling Interests with a Scope Exception 2017 11" 480 260. December 15, 2018, 2017 11 not In June 2018, 2018 07, Compensation – Stock Compensation (Topic 820 2018 07" 718, December 15, 2018, 718 718 718 2018 07 not Application of New or Revised Accounting Standards —Not Yet Adopted In August 2018, 2018 13, Fair Value Measurement (Topic 820 2018 13" 820, Conceptual Framework for Financial Reporting—Chapter 8: August 28, 2018, December 15, 2019, 3 not 2018 13

Note C - Accounts and Other Rec

Note C - Accounts and Other Receivables	12 Months Ended
	Dec. 31, 2019
Notes to Financial Statements
Loans, Notes, Trade and Other Receivables Disclosure [Text Block]	C. Accounts and Other Receivables Accounts and other receivables consist of the following (in thousands): December 31, 2019 2018 Accounts receivable $ 1,681 $ - Other receivables 184 140 Total accounts and other receivables $ 1,865 $ 140

Note D - Prepaid Expenses and O

Note D - Prepaid Expenses and Other Current Assets	12 Months Ended
	Dec. 31, 2019
Notes to Financial Statements
Other Current Assets [Text Block]	D. Prepaid Expenses and Other Current Assets Prepaid expenses and other current assets consist of the following (in thousands): December 31, 2019 2018 Prepaid insurance $ 250 $ 224 Deferred direct contract acquisition costs 805 - Prepaid offering costs 266 - Other prepaid expenses and current assets 231 1,688 Total prepaid expenses and other current assets $ 1,552 $ 1,912

Note E - Property and Equipment

Note E - Property and Equipment	12 Months Ended
	Dec. 31, 2019
Notes to Financial Statements
Property, Plant and Equipment Disclosure [Text Block]	E. Property and Equipment Property and equipment consists of the following (in thousands): December 31, 2019 2018 Laboratory equipment $ 638 $ 1,035 Furniture and office equipment 119 655 Computers and hardware 303 299 Leasehold improvements 958 1,017 Finance lease right-of-use assets 1,013 - Total property and equipment 3,031 3,006 Less: accumulated depreciation and amortization (1,560 ) (1,253 ) Property and equipment, net $ 1,471 $ 1,753 The estimated useful lives of property and equipment are as follows: Useful Life Asset Category (in years) Laboratory equipment 10 Furniture and office equipment 5 10 Computers and hardware 3 7 Leasehold improvements 9 Depreciation and amortization expense, including amounts pertaining to assets held under finance leases, was approximately $304,000 $324,000 December 31, 2019 2018

Note F - Accounts Payable and A

Note F - Accounts Payable and Accrued Expenses	12 Months Ended
	Dec. 31, 2019
Notes to Financial Statements
Accounts Payable, Accrued Liabilities, and Other Liabilities Disclosure, Current [Text Block]	F. Accounts Payable and Accrued Expenses Accounts payable and accrued expenses consist of the following (in thousands): December 31, 2019 2018 Accrued interest $ 359 $ 1,921 Accrued banking fees 700 700 Accrued severance - 193 Accrued payroll 1 731 Accrued professional fees 2,364 230 Accounts payable 1,140 3,715 Other accrued expenses 347 852 Total accounts payable and accrued expenses $ 4,911 $ 8,342

Note G - Debt Obligations

Note G - Debt Obligations	12 Months Ended
	Dec. 31, 2019
Notes to Financial Statements
Debt Disclosure [Text Block]	G. Debt Obligations As of December 31, 2019 2018, December 31, 2019 2018 Deerfield Convertible Note $ 6,981 $ 6,667 2021 Notes 3,000 76,673 December 2019 Notes 70,218 - Total outstanding principal on debt obligations 80,199 83,340 Less: debt issuance costs and discounts (2,856 ) (1,902 ) Convertible notes, net $ 77,343 $ 81,438 Deerfield Facility Agreement In June 2014, $60 first $15 $10 no may $5.85 The Deerfield Convertible Note originally bore interest at 9.75% 6.75%. one third fourth fifth June 2018 June 2019). June 2018, $3,333,333 $168,288 598,568 September 2019, 9.75% 6.75%, June 1, 2020 "2021 September 2019"). December 2019, March 31, 2021 "2021 December 2019"). $6,980,824 March 31, 2021. not Pursuant to the Deerfield Facility Agreement, the Company issued to Deerfield 1,923,077 256,410 The Company also issued to Deerfield a warrant to purchase 14,423,076 $0.78 June 2, 2024 1,923,077 $5.85 260, may The Company recorded the fair value of the shares of Series D Preferred to debt issuance costs on the date of issuance. The Company also recorded the fair value of the Deerfield Warrant and the embedded Warrant Put Option to debt discount on the date of issuance. The debt issuance costs and debt discount are amortized over the term of the related debt and the expense is recorded as interest expense related to amortization of debt issuance costs and discount in the statements of operations. Pursuant to the Deerfield Facility Agreement, the Company may not $750,000 The Deerfield Facility Agreement also includes high yield discount obligation protections that went into effect in June 2019. 1986 Issuance of 5.50% Notes and Third Amendment to Senior Secured Convertible Note and Warrant In February 2016, $86.3 5.50% 2021 “2021 2021 144A The 2021 February 9, 2016 2021 February 1 August 1 August 1, 2016, 5.50% 2021 February 1, 2021 The net proceeds from the Note Offering were approximately $82.8 $18.6 The 2021 not no 2021 2021 58.4454 $1,000 2021 $17.11 If the Company underwent a “fundamental change” (as defined in the Indenture), holders could have required that the Company repurchase for cash all or any portion of their 2021 100% 2021 December 31, 2019, The Indenture included customary terms and covenants, including certain events of default after which the 2021 may As described in more detail below, in multiple exchanges occurring in October 2018, December 2019 January 2020, 2021 Facility Agreement Waiver and Fifth Amendment to Senior Secured Convertible Note In June 2018, $3,333,333 $168,288 598,568 June 2, 2018; ( 2021 October 2018 In October 2018, “October 2018 October 2018 $9,577,000 2021 9,577 $0.0001 As a condition to closing of the October 2018 Each share of Series A Preferred Stock has an aggregate stated value of $1,000 $3.00 October 2018 3,192,333 December 31, 2019, 9,577 October 2018 3,192,333 2021 September 2019 In September 2019, “September 2019 September 2019 1,499,894 1,576 1 $0.0001 1 1 $3,000,000 2021 September 2019 $27,000,000 2021 2 $0.0001 2 1 September 2019 2 $1,000 $0.9494, 15 As a condition to closing of the September 2019 1 1 2 2 1 2 Each share of Series B- 1 $1,000 $0.9494 September 2019 1,659,996 1 2 $1,000 $0.9494 15 September 2019 28,439,015 2 The Series B Preferred Stock is convertible at any time at the option of the Deerfield Lenders; provided that the Deerfield Lenders are prohibited from converting shares of Series B Preferred Stock into shares of common stock if, as a result of such conversion, such holders (together with certain affiliates and “group” members of such holders) would beneficially own more than 4.985% not $0.0001 not not not 1 2 1 2 As of December 31, 2019, 1,576 1 1,659,966 no 2 The September 2019 9.75% 6.75%, June 1, 2020. September 2019 September 2019 $150,000 September 2019 The Company determined the changes to the Deerfield Facility Agreement met the definition of a troubled debt restructuring under ASC 470 60, Troubled Debt Restructurings by Debtors no The changes to the 2021 September 2019 $2.3 2021 2021 December 2019 In December 2019, December 2019 “December 2019 “December 2019 December 2019 $71,418,011 “December 2019 $71,418,011 2021 December 2019 December 2019 $745,011 50% December 18, 2019, 2021 December 2019 December 2019 The December 2019 6.75% December 2019 $17.11 2021 December 2019 December 2019 4,174,051 December 2019 $5.85 December 2019 December 2019 415 1933, December 2019 $5.85 not x September 2019 December 2019 not December 2019 $0.583 December 2019 December 2019 4.985% December 2019 4.985% 19.985% December 2019 December 2019 December 2019 March 31, 2021, not December 2019 December 2019 December 2019 December 2019 December 2019 December 2019 The December 2019 December 2019 December 2019 December 2019 February 14, 2020 June 1, 2020, March 31, 2021, March 31, 2021 may The December 2019 December 2019 December 2019 $5.85 $0.583. The December 2019 December 2019 The December 2019 December 2019 may one In connection with entering into the December 2019 December 18, 2019, June 2, 2014, In connection with entering into the December 2019 “September 2019 September 2019 September 2019 December 2019 September 2019 September 2019 x $0.60, 15 no 28,439,015 September 2019 2 September 2019 may September 2019 September 2019 September In connection with entering into the September 2019 2 2 2 2 September 2019 $0.60 15 As of December 31, 2019, $1.2 December 2019 2,000,000 The Company determined the changes to the Deerfield Convertible Note met the definition of a troubled debt restructuring under ASC 470 60, Troubled Debt Restructurings by Debtors no The changes to the 2021 December 2019 December 2019 December 2019 2021 January 2020 In January 2020, January 2020 "January 2020 January 2020 $3,037,354 "January 2020 $3,037,354 2021 January 2020 $37,354, 50% January 13, 2020, 2021 January 2020 The January 2020 December 2019 In connection with entering into the January 2020 December 2019 "December 2019 December 2019 December 2019 December 2019 $17.11 $5.85 December 2019 $0.38 $0.583 x 2020 Convertible Notes Future minimum principal payments under convertible notes as of December 31, 2019 , Convertible Year Ending December 31, Notes 2020 $ - 2021 80,199 Total minimum principal payments 80,199 Less: debt issuance costs and discounts (2,856 ) Convertible notes, net $ 77,343 Line of Credit During the second 2016, March 2019,

Note H - Commitments and Contin

Note H - Commitments and Contingencies	12 Months Ended
	Dec. 31, 2019
Notes to Financial Statements
Commitments and Contingencies Disclosure [Text Block]	H. Commitments and Contingencies Legal Matters From time to time, the Company is involved in various legal proceedings arising in the normal course of business. For some matters, a liability is not not December 31, 2019 2018 no . Lease Agreements We have operating and finance leases for office space, laboratory facilities and various laboratory equipment, furniture and office equipment and leasehold improvements. Our leases have remaining lease terms of 1 6 5 1 Florida The Company leases office space in Florida, comprised of two non-cancelable operating leases, which expire in August 2025 February 2026, two five 2020, one two 2026. Iowa The Company leases office and laboratory facilities in Iowa under a non-cancelable operating lease. The Company’s lease for its Iowa facilities expires in September 2020 one Virginia The Company leases office and laboratory facilities in Virginia under a non-cancelable operating lease. The Company’s lease for its Virginia facilities expires in August 2020. North Carolina The Company leased office space in North Carolina under a non-cancelable operating lease. The original expiration date of the Company ’s lease was May 2020 second 2017 third third 2019, Capital Lease The Company leases various laboratory equipment, furniture and office equipment and leasehold improvements that are accounted for as capital leases and that require ongoing payments, including interest expense. The capital leases are financed through various financial institutions and are collateralized by the underlying assets. As of December 31, 2019 2018 , 7.19 9.57 The components of lease expense were as follows (in thousands): Year Ended December 31, Lease Cost 2019 Finance lease cost: Amortization of right-of-use assets $ 123 Interest on lease liabilities 40 Total finance lease cost 163 Operating lease cost 473 Short-term lease cost 232 Variable lease cost 48 Less: sublease income (84 ) Total lease costs $ 832 Rent expense for non-cancelable operating leases was $ 0.7 million for the year ended December 31, 2019 2018 Supplemental cash flow information related to leases was as follows (in thousands): Year Ended December 31, 2019 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from finance leases $ 40 Financing cash flows from finance leases 207 Operating cash flows from operating leases 435 Operating cash flows from short-term leases 232 Operating cash flows from variable lease costs 48 Right-of-use assets obtained in exchange for lease liabilities: Finance leases $ 757 Operating leases 1,852 Supplemental balance sheet information related to leases was as follows (in thousands, except weighted average remaining lease term and weighted average discount rate): December 31, 2019 Finance Leases Property and equipment, at cost $ 1,013 less: accumulated depreciation and amortization (398 ) Property and equipment, net $ 615 Other current liabilities $ 236 Other long-term liabilities 168 Total finance lease liabilities $ 404 Operating Leases Operating lease right-of-use assets $ 1,537 Total operating lease right-of-use assets $ 1,537 Current portion of operating lease liabilities $ 284 Operating lease liabilities, less current portion 1,901 Total operating lease liabilities $ 2,185 Weighted Average Remaining Lease Term Finance leases 2 years Operating leases 6 years Weighted Average Discount Rate Finance leases 7.7 % Operating leases 7.5 % Maturities on lease liabilities were as follows (in thousands): Finance Operating Year Ending December 31, Leases Leases 2020 $ 260 $ 438 2021 163 449 2022 11 461 2023 - 472 2024 - 484 Thereafter - 420 Total lease payments 434 2,724 Less: future interest expense (30 ) (539 ) Lease liabilities $ 404 $ 2,185

Note I - Supply Arrangement

Note I - Supply Arrangement	12 Months Ended
	Dec. 31, 2019
Notes to Financial Statements
Collaborative Arrangement Disclosure [Text Block]	I. Supply Arrangement As of December 31, 2019 2018 , one potential future expenditures related to research and development. In November 2009, Supply Agreement”) with Johnson Matthey Inc. (“JMI”) whereby JMI has agreed to supply the Company with all of the benzhydrocodone necessary for clinical trials and commercial sale for a price equal to JMI’s manufacturing cost and to provide process optimization and development services for benzhydrocodone. The Company’s FDA-approved drug, APADAZ, contains benzhydrocodone. Expense of $3.2 $3.6 December 31, 2019 , respectively. The Company must purchase all of its U.S. benzhydrocodone needs from JMI and JMI cannot supply benzhydrocodone to other companies. The term of the Supply Agreement extends as long as the Company holds a valid and enforceable patent for benzhydrocodone or until the tenth two 12 not No

Note J - Preferred Stock and Wa

Note J - Preferred Stock and Warrants	12 Months Ended
	Dec. 31, 2019
Notes to Financial Statements
Preferred Stock [Text Block]	J. Preferred Stock and Warrants Authorized, Issued, and Outstanding Preferred Stock As of December 31, 2019, 10,000,000 9,578 1,576 1 27,000 2 9,577 1,576 1 December 31, 2019. No 1 December 31, 2019. December 31, 2018, 9,577 3,337 no 1 No 2 December 31, 2019 December 31, 2018 no December 31, 2018. In October 2018, October 2018 October 2018 9,577 $1,000 $3.00 October 2018 3,192,333 December 31, 2019 In September 2019, September 2019 September 2019 1,576 1 1 $1,000 $0.9494, 15 September 2019 1,659,996 1 4.985% not $0.0001 not not not 1 2 1 2 December 31, 2019, 1,576 1 1,659,996

Note K - Common Stock and Warra

Note K - Common Stock and Warrants	12 Months Ended
	Dec. 31, 2019
Notes to Financial Statements
Stockholders' Equity Note Disclosure [Text Block]	K. Common Stock and Warrants Authorized, Issued, and Outstanding Common Shares As of December 31, 2019 2018 authorized shares of common stock of 250,000,000 36,350,785 26,455,352 December 31, 2019 2018 As of December 31, 2019 2018 December 31, 2019 2018 Conversion of Deerfield Convertible Note 1,213,606 1,167,607 Conversion of 2021 Notes 175,336 4,481,182 Conversion of 2019 Notes not subject to the Deerfield Optional Conversion Feature 3,186,770 - Outstanding awards under equity incentive plans 5,192,222 3,704,755 Outstanding common stock warrants 2,423,077 2,527,763 Conversion of Series A Preferred Stock - 1,112,334 In exchange for the Deerfield Optional Conversion Feature* 26,439,015 - Possible future issuances under the Prior Purchase Agreement 9,553,046 - Possible future issuances under equity incentive plans 84,616 648,272 Total common shares reserved for future issuance 48,267,688 13,641,913 Common Stock Activity The following table summarizes common stock activity for the years ended December 31, 2019 2018 Shares of Common Stock Balance as of January 1, 2018 14,657,430 Common stock sold under First ATM Agreement 762,338 Common stock issued as a result of Deerfield Convertible Note principal and interest conversion 598,568 Common stock options exercised 23,682 Common stock sold under underwritten public offering 8,333,334 Common stock issued as a result of Series A Preferred Stock conversion 2,080,000 Balance as of December 31, 2018 26,455,352 Common stock issued under the Prior Purchase Agreement 3,521,471 Restricted stock vested during the period 101,739 Common stock issued as a result of 2021 Notes principal conversion 1,499,894 Common stock issued as a result of Series B-1 Preferred Stock conversion 1,659,996 Common stock issued as a result of Series A Preferred Stock conversion 1,112,333 Common stock issued as a result of Deerfield Optional Conversion Feature conversion 2,000,000 Balance as of December 31, 2019 36,350,785 In September 2018, 762,338 $4.9 December 31, 2019, not In October 2018, 8,333,334 3. Also in October 2018, October 2018 9,577 December 31, 2019, 9,577 3,192,333 October 2018 On September 3, 2019, September 2019 1,499,894 1,576 1 December 31, 2019, 1,576 1 1,659,966 September 2019 Warrants During 2013, $3.8 “2013 1,079,453 2013 2013 1,079,453 2013 143,466 $5.85 2013 June 2, 2019. On June 2, 2014, 14,423,076 June 2, 2024, 1,923,077 $5.85 The Company determined that the 2013 2013 2013 In connection with a Collaboration and License Agreement (the “APADAZ License Agreement”) with KVK Tech, Inc. (“KVK”), in October 2018, 500,000 $2.30 not four 125,000 500,000 October 24, 2023. may The Company determined that, since KVK qualifies as a customer under ASC 606, 815 815 606

Note L - Stock-based Compensati

Note L - Stock-based Compensation	12 Months Ended
	Dec. 31, 2019
Notes to Financial Statements
Share-based Payment Arrangement [Text Block]	L. Stock-Based Compensation The Company maintains a stock-based compensation plan (the “Incentive Stock Plan”) that governs stock awards made to employees and directors prior to completion of the IPO. In November 2014, April 2015, 2014 “2014 April 2015. 2014 may 2014 5,076,694 December 31, 2019. 2014 January 1 January 1, 2016, January 1, 2024, 4% December 31 2014 January 1, 2020, 2014 1,454,031 During the second 2019, two 2014 first second 2019. first second 2019, 42,436 39,284 In addition, the Company granted to a consultant fully vested RSAs under the 2014 December 31, 2019, 20,019 During the year ended December 31, 2019 no December 31, 2019 2018 23,682 $68,000 $69,000 Stock-based compensation expense recorded unde r the Incentive Stock Plan and the 2014 Year ended December 31, 2019 2018 Research and development $ 1,459 $ 1,608 General and administrative 2,951 3,651 Severance expense - 1,236 Total stock-based compensation expense $ 4,410 $ 6,495 Stock Option Awards The Company estimates the fair value of stock options using the Black-Scholes option-pricing model, which requires the use of subjective assumptions, including the expected term of the option, the expected stock price volatility, expe cted dividend yield and the risk-free interest rate for the expected term of the option. The expected term represents the period of time the stock options are expected to be outstanding. Due to the lack of sufficient historical exercise data to provide a reasonable basis upon which to otherwise estimate the expected term of the stock options, the Company uses the simplified method to estimate the expected term for its “plain vanilla” stock options. Under the simplified method, the expected term of an option is presumed to be the mid-point between the vesting date and the end of the contractual term. Some options, for example those that have exercise prices in excess of the fair value of the underlying stock, are not second ies and the Company over the estimated expected term of the stock options. second The Company assumes no not not The Company recogni zes compensation expense related to stock-based payment transactions upon satisfaction of the requisite service or vesting requirements. Forfeitures are estimated at the time of grant and revised based on actual forfeitures, if necessary, in subsequent periods if actual forfeitures differ from those estimates. Using the Black-Scholes option-pricing model, the weighted-average fair value of awards granted during the years ended December 31, 2019 2018 $1.43 $4.05 re, respectively. The assumptions used to estimate fair value are as follows: Year Ended December 31, 2019 2018 Risk-free interest rate 1.75% 2.61% 2.43% 2.91% Expected term (in years) 5.50 10.00 5.50 6.79 Expected volatility 84.82% 85.93% 83.10% 85.05% Expected dividend yield 0% 0% The activity under the Incentive Stock Plan and the 2014 for the year ended December 31, 2019 , Weighted Weighted Avg Aggregate Number of Average Remaining Intrinsic Options Exercise Price Contractual Term Value Outstanding balance at January 1, 2019 3,704,755 $ 9.35 7.48 $ - Granted 2,291,820 $ 1.84 Exercised or released (101,739 ) $ - Canceled or forfeited (675,950 ) $ 8.80 Expired (26,664 ) $ 4.80 Outstanding balance at December 31, 2019 5,192,222 $ 6.31 7.63 $ - Exercisable at December 31, 2019 2,154,640 $ 10.80 6.04 $ - Vested and expected to vest at December 31, 2019 4,503,063 $ 7.16 7.30 $ - Information regarding currently outstanding and exercisable options as of December 31, 2019 , Options Outstanding Options Exercisable Weighted Avg Weighted Avg Number of Remaining Number of Remaining Exercise Price Shares Contractual Term Shares Contractual Term $0.52 to $5.00 2,902,995 8.72 479,039 7.19 $5.01 to $10.00 1,102,844 6.74 599,969 5.62 $10.01 to $15.00 471,833 5.94 381,208 5.90 $15.01 to $20.00 379,550 5.70 359,424 5.67 $20.01 to $20.45 335,000 5.68 335,000 5.68 5,192,222 7.63 2,154,640 6.04 The total fair value of stock options vested during the years ended December 31, 2019 2018 $4.9 $5.9 Unvested stock options as of December 31, 2019 2018 Number of Unvested Shares December 31, Exercise Price 2019 2018 $0.52 to $5.00 2,423,956 634,751 $5.01 to $10.00 502,875 818,900 $10.01 to $15.00 90,625 186,584 $15.01 to $20.00 20,126 139,988 $20.01 to $20.45 - 86,950 Total number of unvested stock options 3,037,582 1,867,173 As of December 31, 2019 , $3.8 2014 2.29 There was no December 31, 2019 or 2018

Note M - Fair Value of Financia

Note M - Fair Value of Financial Instruments	12 Months Ended
	Dec. 31, 2019
Notes to Financial Statements
Fair Value Disclosures [Text Block]	M. Fair Value of Financial Instruments The carrying amounts of certain financial instruments, including cash and cash equivalents, restricted cash and accounts payable and accrued expenses, approximate their respective fair values due to the short-term nature of such instruments. The fair value of the Deerfield Convertible Note was $6.0 $6.2 December 31, 2019 2018 2021 $2.4 $51.2 December 31, 2019 2018 2019 $57.0 31, 2019. 2021 2019 3 2021 2019 as of December 31, 2019 2018 Assets and Liabilities Measured at Fair Value on a Recurring Basis The Company evaluates its financial assets and liabilities subject to fair value measurements on a recurring basis to determine the appropriate level in whi ch to classify them for each reporting period. This determination requires significant judgments to be made. The following table summarizes the conclusions reached regarding fair value measurements as of December 31, 2019 2018 Quoted Prices Significant in Active Other Significant Balance at Markets for Observable Unobservable December 31, Identical Assets Inputs Inputs 2019 (Level 1) (Level 2) (Level 3) Deerfield Warrant liability $ 77 $ - $ - $ 77 Embedded Warrant Put Option 19 - - 19 Fundamental change and make-whole interest provisions embedded within 2021 Notes - - - - Deerfield Note Conversion Feature - - - - KVK Warrant liability 24 - 24 - Total liabilities $ 120 $ - $ 24 $ 96 Quoted Prices Significant in Active Other Significant Balance at Markets for Observable Unobservable December 31, Identical Assets Inputs Inputs 2018 (Level 1) (Level 2) (Level 3) Deerfield Warrant liability $ 1,557 $ - $ - $ 1,557 Embedded Warrant Put Option 154 - - 154 Fundamental change and make-whole interest provisions embedded within 2021 Notes - - - - Deerfield Note Conversion Feature 134 - - 134 KVK Warrant liability 273 - 273 - Total liabilities $ 2,118 $ - $ 273 $ 1,845 Trading securities: Certificates of deposit 246 246 - - U.S. Treasury securities 3,014 3,014 - - Total assets $ 3,260 $ 3,260 $ - $ - The Company’s Deerfield Warrant liability, embedded Warrant Put Option, the fundamental change and the make-whole interest provisions embedded in the 2021 December 31, 2019 December 31, 2018, 2021 December 31, 2018, 2021 December 31, 2019 December 31, 2018. 2021 December 31, 2019 2018 The Company’s KVK Warrant liability is measured at fair value on a recurring basis. As of December 31, 2019 December 31, 2018, no not not December 31, 2019 2018 A reconciliation of the beginning and ending balances for the derivative and warrant liability measured at fair value on a recurring basis using signific ant unobservable inputs (Level 3 2019 2018 Balance as of beginning of period $ 1,845 $ 7,709 Gain on extinguishment of debt - (2 ) Adjustment to fair value (1,749 ) (5,862 ) Balance as of end of period $ 96 $ 1,845

Note N - Income Taxes

Note N - Income Taxes	12 Months Ended
	Dec. 31, 2019
Notes to Financial Statements
Income Tax Disclosure [Text Block]	N. Income Taxes The Company ’s financial statements include a total state tax benefit related to research and development credits of $22,000 $126,000 $24.2 $56.6 December 31, 2019 2018 Year ended December 31, 2019 2018 Federal statutory rate 21.00 21.00 Effect of: Change in valuation allowance (28.52 ) (30.44 ) Return to provision and deferred true-up - 0.38 Change in rate (0.33 ) 0.03 State tax benefit (net of federal) 3.39 4.35 Warrant liability 1.71 2.02 State research and development credit 0.09 0.22 Federal research and development credit 1.44 3.30 Amortization (0.29 ) - Stock-based compensation (1.10 ) (0.63 ) Other 2.70 (0.01 ) Federal income tax provision effective rate 0.09 0.22 The components of deferred tax assets and liabilities are as follows (in thousands): December 31, 2019 2018 Deferred tax assets relating to: Net operating loss carryforwards $ 56,827 $ 51,269 Research and development tax carryforward 6,411 5,657 Other deferred tax assets 4,488 3,437 Total gross deferred tax assets 67,726 60,363 Deferred tax liabilities relating to: Property and equipment - 161 Other deferred tax liabilities 540 10 Total gross deferred tax liabilities 540 171 Deferred tax assets less liabilities 67,186 60,192 Valuation allowance (67,186 ) (60,192 ) Net deferred tax asset (liability) $ - $ - In assessing the realizability of deferred tax assets, management considers whether it is more likely than not not assets is dependent upon the generation of future taxable income during the periods in which those temporary differences become deductible. Management considers the scheduled reversal of deferred tax liabilities, projected future taxable income and tax planning strategies in making this assessment. Based upon the level of historical taxable income and projections for future taxable income over the periods in which the deferred tax assets are deductible, management believes it is more likely than not not The Company had the following federal net operating loss carryforward and research activities credits as of December 31, 2019 ( Net Operating Research Year Incurred Loss CF Activities Cr. Expiration 2007 $ 454 $ 30 2027 2008 1,178 65 2028 2009 3,060 176 2029 2010 3,423 149 2030 2011 9,929 176 2031 2012 - 170 2032 2013 4,353 133 2033 2014 15,897 894 2034 2015 23,496 598 2035 2016 41,580 745 2036 2017 34,776 652 2037 2018 56,155 2,272 Indefinite 2019 22,784 352 Indefinite $ 217,085 $ 6,412 The Company also has certain state net operating loss carryforwards totaling $136.0 2027 2037. may 382 may imitations on the Company’s ability to utilize the net operating loss carryforward. ASC 740 10, Accounting for Uncertainty in Income Taxes not” not not not not

Note O - Net Loss Per Share

Note O - Net Loss Per Share	12 Months Ended
	Dec. 31, 2019
Notes to Financial Statements
Earnings Per Share [Text Block]	O. Net Loss Per Share Under the two No no two two The following table summarizes the computation of basic and diluted net loss and net loss per share of common stock of the Company (in thousands, except share and pe r share amounts): Year Ended December 31, 2019 2018 Net loss - basic and diluted $ (24,522 ) $ (56,466 ) Weighted average number of shares of common stock - basic and diluted 29,654,968 17,930,023 Net loss per share - basic and diluted $ (0.83 ) $ (3.15 ) Diluted net loss per share of common stock is the same as basic net loss per share of common stock for all periods presented because the effects of potentially dilutive items were anti-dilutive given the Company ’s net loss. The following securities, presented on a common stock equivalent basis, have been excluded from the calculation of weighted average number of shares of common stock outstanding because their effect is anti-dilutive: December 31, 2019 2018 Deerfield Convertible Note 1,213,606 1,167,607 2021 Notes 175,336 4,481,182 2019 Notes* 29,625,785 - Awards under equity incentive plans 5,192,222 3,704,755 Common stock warrants 2,423,077 2,527,763 Series A Convertible Preferred Stock - 1,112,334 Total securities excluded from the calculation of weighted average number of shares of common stock outstanding 38,630,026 12,993,641 * Inclusive of 26,439,015 2

Note P - Severance Expense

Note P - Severance Expense	12 Months Ended
	Dec. 31, 2019
Notes to Financial Statements
Restructuring and Related Activities Disclosure [Text Block]	P. Severance Expense On August 31, 2018, $0.4 $1.2 December 31, 2018. December 31, 2018, $0.2 No December 31, 2019. On February 7, 2020, $1.0 twelve $0.4 $0.6

Note Q - Employee Benefit Plan

Note Q - Employee Benefit Plan	12 Months Ended
	Dec. 31, 2019
Notes to Financial Statements
Compensation and Employee Benefit Plans [Text Block]	Q. Employee Benefit Plan The Company has a 401 401 may 4% 401 $133,000 $212,000 December 31, 2019 2018 The Company has a discretionary profit sharing plan (the “ Profit Sharing Plan”) that covers all employees. Employees become eligible participants in the Profit Sharing Plan once they have provided three no 2019 2018.

Significant Accounting Policies

Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Use of Estimates, Policy [Policy Text Block]	Use of Estimates The preparation of financial statements in conformity with U.S. generally accepted accounting principles ("GAAP") requires the Company to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates. On an ongoing basis, the Company evaluates its estimates and assumptions, including those related to revenue recognition, the useful lives of property and equipment, the recoverability of long-lived assets, the incremental borrowing rate for leases, and assumptions used for purposes of determining stock-based compensation, income taxes, and the fair value of the derivative and warrant liability, among others. The Company bases its estimates on historical experience and on various other assumptions that it believes to be reasonable, the results of which form the basis for making judgments about the carrying value of assets and liabilities.
Reclassification, Policy [Policy Text Block]	Reclassifications During 2019, $0.1 December 31, 2018 $0.1 December 31, 2018. no
Concentration Risk, Credit Risk, Policy [Policy Text Block]	Concentration of Credit Risk Financial instruments that potentially expose the Company to concentrations of credit risk consist principally of cash on deposit with multiple financial institutions, the balances of which frequently exceed insured limits.
Cash and Cash Equivalents, Policy [Policy Text Block]	Cash and Cash Equivalents The Company considers any highly liquid investm ents with an original maturity of three
Marketable Securities, Policy [Policy Text Block]	Marketable Securities and Long-term Investments The Company maintained investment securities that were classified as trading securities. These securities were carried at fair value with unreali zed gains and losses included in other (expense) income on the statements of operations. The securities primarily consisted of certificates of deposit, U.S. Treasury securities and U.S. government-sponsored agency securities.
Property, Plant and Equipment, Policy [Policy Text Block]	Property and Equipment The Company records property and equipment at cost less accumulated depreciation and amortization. Costs of renewals and improvements that extend the useful lives of the assets are capitalized. Maintenance and repairs are expensed as incurred. Depreciation is determined on a straight-line basis over the estimated useful lives of the assets, which generally range from three ten
Debt, Policy [Policy Text Block]	Debt Issuance Costs Debt issuance costs incurred in connection with financing arrangements are recorded as a reduction of the related debt on the balance sheet and amortiz ed over the life of the respective financing arrangement using the effective interest method.
Collaborative Arrangement, Accounting Policy [Policy Text Block]	Supply Arrangements The Company enters into supply arrangements for the supply of components of its product and product candidates. These arrangements also may share of future revenue if related product or product candidates reach commercialization. Costs under these supply arrangements, if any, are expensed as incurred (Note I).
Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]	Impairment of Long-Lived Assets Long-lived assets to be held and used are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amounts of the assets may not When such events occur, the Company compares the carrying amounts of the assets to their undiscounted expected future cash flows. If the undiscounted cash flows are insufficient to recover the carrying values, an impairment loss is recorded for the difference between the carrying values and fair values of the asset. No December 31, 2019 2018 .
Fair Value of Financial Instruments, Policy [Policy Text Block]	Fair Value of Financial Instruments Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date, based on the Company’s principal or, in absence of a principal, most advantageous market for the specific asset or liability. The Company uses a three equent to their initial measurement. The hierarchy requires the Company to use observable inputs when available, and to minimize the use of unobservable inputs, when determining fair value. The three ● Level 1 —Observable inputs that reflect quoted market prices (unadjusted) for identical assets or liabilities in active markets; ● Level 2 —Observable inputs other than quoted prices in active markets that are observable either directly or indirectly in the marketplace for identical or similar assets and liabilities; and ● Level 3 —Unobservable inputs that are supported by little or no
Revenue from Contract with Customer [Policy Text Block]	Revenue Recognition The Company commenced recognizing revenue in accordance with the provisions of ASC 606, Revenue from Contracts with Customers 606” January 1, 2018. no Arrangements with Multiple-Performance Obligations From time to time, the Company enters into arrangements for research and development, manufacturing and/or commercialization services. Such arrangements may In arrangements involving more than one not The consideration allocated to each distinct performance obligation is recognized as revenue when control of the related goods or services is transferred. Consideration associated with at-risk substantive performance milestones is recognized as revenue when it is probable that a significant reversal of the cumulative revenue recognized will not Licensing Agreements The Company enters into licensing agreements with licensees that fall under the scope of ASC 606. The terms of the Company’s licensing agreements typically include one may As part of the accounting for these agreements, the Company must develop estimates and assumptions that require judgment to determine the underlying stand-alone selling price for each performance obligation which determines how the transaction price is allocated among the performance obligations. Generally, the estimation of the stand-alone selling price may Up-front Fees: Milestone Payments: not not not may KP415 In September 2019, KP415 KP415, KP484, KP879, KP922 KP415 In exchange for the exclusive, worldwide license, discussed above, Commave paid the Company a non-refundable upfront payment of $10.0 $63.0 KP415 KP484. $420.0 KP415 KP415 KP415 Commave also agreed to be responsible for and reimburse the Company for all of development, commercialization and regulatory expenses incurred on the licensed products, subject to certain limitations as set forth in the KP415 The KP415 606, not KP415 606, third two $10.0 KP415 The consideration allocated to the grant of the exclusive, worldwide license was $10.0 KP415 KP415 The consideration allocated to the performance of consulting services, which includes the reimbursement of out-of-pocket third KP415 third third no third third third third 606 third KP415 third KP415 KP415 December 31, 2019, 66% third Under the KP415 KP415 KP415 first not third 606 not not The Company is entitled to additional payments from Commave conditioned upon the achievement of specified regulatory milestones related to KP415 KP484 KP415 KP415 KP415 not not not For the year ended December 31, 2019, $12.8 $10.0 $1.1 third $1.7 December 31, 2019, $1.4 $0.2 third $10.0 KP415 10% third 2019. 340 40, $2.8 KP415 third December 31, 2019, $1.9 no December 31, 2018. no December 31, 2019 2018.
Receivable [Policy Text Block]	Accounts and Other Receivables Accounts and other receivables consists of receivables under the KP415 KP415 third December 31, 2019 2018 no
Research and Development Expense, Policy [Policy Text Block]	Research and Development Major components of research and development costs include cash compensation, stock-based compensation, depreciation and amortization expense on research and development property and equipment, costs of preclinical studies, clin ical trials and related clinical manufacturing, costs of drug development, costs of materials and supplies, facilities cost, overhead costs, regulatory and compliance costs, and fees paid to consultants and other entities that conduct certain research and development activities on the Company’s behalf. Costs incurred in research and development are expensed as incurred. The Company records nonrefundable advance payments it makes for future research and development activities as prepaid expenses. Prepaid expenses are recognized as expense in the statements of operations as the Company receives the related goods or services. The Company enters into contractual agreements with third pleted over an extended period of time. The Company records liabilities under these contractual commitments when an obligation has been incurred. This accrual process involves reviewing open contracts and purchase orders, communicating with the applicable personnel to identify services that have been performed and estimating the level of service performed and the associated cost when the Company has not
Intangible Assets, Finite-Lived, Policy [Policy Text Block]	Patent Costs Patent costs, including related legal costs, are expensed as incurred and recorded within general and administrative expenses on the statements of operations.
Income Tax, Policy [Policy Text Block]	Income Taxes The Company recognizes deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the financial reporting and tax basis of assets and liabilities, as well as for operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using the tax rates that are expected to apply to taxable income for the years in which those tax assets and liabilities are expected to be realized or settled. Valuation allowances are recorded to reduce deferred tax assets to the amount the Company believes is more likely than not Uncertain tax positions are recognized only when the Company believes it is more likely than not t the tax position will be upheld on examination by the taxing authorities based on the merits of the position. The Company recognizes interest and penalties, if any, related to unrecognized income tax uncertainties in income tax expense. The Company did not December 31, 2019 2018 The Company files income tax returns in the United States for federal and various state jurisdictions. With few exceptions, the Company is no 2014, 2014 may No
Share-based Payment Arrangement [Policy Text Block]	Stock-Based Compensation The Company measures and recognizes compensation expense for all stock-based payment awards made to employees, officers an d directors based on the estimated fair values of the awards as of the grant date. The Company records the value of the portion of the award that is ultimately expected to vest as expense over the requisite service period. The Company also accounts for equity instruments issued to non-employees using a fair value approach under Accounting Standards Codification ("ASC") subtopic 505 50, 2018 07.
Earnings Per Share, Policy [Policy Text Block]	Basic and Diluted Net Loss per Share of Common Stock The Company uses the two entitle the holders to participate in dividends and earnings of the Company. The two
Segment Reporting, Policy [Policy Text Block]	Segment and Geographic Information Operating segments are defined as components of an enterprise (business activity from which it earns revenue and incurs expenses) for which discrete financial information is ava ilable and regularly reviewed by the chief operating decision maker ("CODM") in deciding how to allocate resources and in assessing performance. The Company’s CODM is its Chief Executive Officer. The Company views its operations and manages its business as a single operating and reporting segment. All assets of the Company were held in the United States as of December 31, 2019 2018
New Accounting Pronouncements, Policy [Policy Text Block]	Application of New or Revised Accounting Standards —Adopted From time to time, the Financial Accounting Standards Board (the “FASB”) or other standard-setting bodies issue accounting standards that are adopted by the Company as of the specified effective date. In April 2012, not In February 2016, 2016 02, Leases (Topic 842 ) 2016 02” January 1, 2019 not 12 not 2016 02 $2.6 January 1, 2019. In July 2017, 2017 11, Earnings Per Share (Topic 260 ), Distinguishing Liabilities from Equity (Topic 480 ), Derivatives and Hedging (Topic 815 ) – I. Accounting for Certain Financial Instruments with Down Round Features and II. Replacement of the Indefinite Deferral for Mandatorily Redeemable Financial Instruments of Certain Nonpublic Entities and Certain Mandatorily Redeemable Noncontrolling Interests with a Scope Exception 2017 11" 480 260. December 15, 2018, 2017 11 not In June 2018, 2018 07, Compensation – Stock Compensation (Topic 820 2018 07" 718, December 15, 2018, 718 718 718 2018 07 not Application of New or Revised Accounting Standards —Not Yet Adopted In August 2018, 2018 13, Fair Value Measurement (Topic 820 2018 13" 820, Conceptual Framework for Financial Reporting—Chapter 8: August 28, 2018, December 15, 2019, 3 not 2018 13

Note C - Accounts and Other R_2

Note C - Accounts and Other Receivables (Tables)	12 Months Ended
	Dec. 31, 2019
Notes Tables
Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block]	December 31, 2019 2018 Accounts receivable $ 1,681 $ - Other receivables 184 140 Total accounts and other receivables $ 1,865 $ 140

Note D - Prepaid Expenses and_2

Note D - Prepaid Expenses and Other Current Assets (Tables)	12 Months Ended
	Dec. 31, 2019
Notes Tables
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Table Text Block]	December 31, 2019 2018 Prepaid insurance $ 250 $ 224 Deferred direct contract acquisition costs 805 - Prepaid offering costs 266 - Other prepaid expenses and current assets 231 1,688 Total prepaid expenses and other current assets $ 1,552 $ 1,912

Note E - Property and Equipme_2

Note E - Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2019
Notes Tables
Property, Plant and Equipment [Table Text Block]	December 31, 2019 2018 Laboratory equipment $ 638 $ 1,035 Furniture and office equipment 119 655 Computers and hardware 303 299 Leasehold improvements 958 1,017 Finance lease right-of-use assets 1,013 - Total property and equipment 3,031 3,006 Less: accumulated depreciation and amortization (1,560 ) (1,253 ) Property and equipment, net $ 1,471 $ 1,753
Property, Plant and Equipment, Useful Life [Table Text Block]	Useful Life Asset Category (in years) Laboratory equipment 10 Furniture and office equipment 5 10 Computers and hardware 3 7 Leasehold improvements 9

Note F - Accounts Payable and_2

Note F - Accounts Payable and Accrued Expenses (Tables)	12 Months Ended
	Dec. 31, 2019
Notes Tables
Schedule of Accounts Payable and Accrued Liabilities [Table Text Block]	December 31, 2019 2018 Accrued interest $ 359 $ 1,921 Accrued banking fees 700 700 Accrued severance - 193 Accrued payroll 1 731 Accrued professional fees 2,364 230 Accounts payable 1,140 3,715 Other accrued expenses 347 852 Total accounts payable and accrued expenses $ 4,911 $ 8,342

Note G - Debt Obligations (Tabl

Note G - Debt Obligations (Tables)	12 Months Ended
	Dec. 31, 2019
Notes Tables
Convertible Debt [Table Text Block]	December 31, 2019 2018 Deerfield Convertible Note $ 6,981 $ 6,667 2021 Notes 3,000 76,673 December 2019 Notes 70,218 - Total outstanding principal on debt obligations 80,199 83,340 Less: debt issuance costs and discounts (2,856 ) (1,902 ) Convertible notes, net $ 77,343 $ 81,438
Schedule of Maturities of Long-term Debt [Table Text Block]	Convertible Year Ending December 31, Notes 2020 $ - 2021 80,199 Total minimum principal payments 80,199 Less: debt issuance costs and discounts (2,856 ) Convertible notes, net $ 77,343

Note H - Commitments and Cont_2

Note H - Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2019
Notes Tables
Lease, Cost [Table Text Block]	Year Ended December 31, Lease Cost 2019 Finance lease cost: Amortization of right-of-use assets $ 123 Interest on lease liabilities 40 Total finance lease cost 163 Operating lease cost 473 Short-term lease cost 232 Variable lease cost 48 Less: sublease income (84 ) Total lease costs $ 832
Schedule of Leases Cash Flow Information [Table Text Block]	Year Ended December 31, 2019 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from finance leases $ 40 Financing cash flows from finance leases 207 Operating cash flows from operating leases 435 Operating cash flows from short-term leases 232 Operating cash flows from variable lease costs 48 Right-of-use assets obtained in exchange for lease liabilities: Finance leases $ 757 Operating leases 1,852
Schedule of Leases Balance Sheet Information [Table Text Block]	December 31, 2019 Finance Leases Property and equipment, at cost $ 1,013 less: accumulated depreciation and amortization (398 ) Property and equipment, net $ 615 Other current liabilities $ 236 Other long-term liabilities 168 Total finance lease liabilities $ 404 Operating Leases Operating lease right-of-use assets $ 1,537 Total operating lease right-of-use assets $ 1,537 Current portion of operating lease liabilities $ 284 Operating lease liabilities, less current portion 1,901 Total operating lease liabilities $ 2,185 Weighted Average Remaining Lease Term Finance leases 2 years Operating leases 6 years Weighted Average Discount Rate Finance leases 7.7 % Operating leases 7.5 %
Operating and Finance Lease, Liability, Maturity [Table Text Block]	Finance Operating Year Ending December 31, Leases Leases 2020 $ 260 $ 438 2021 163 449 2022 11 461 2023 - 472 2024 - 484 Thereafter - 420 Total lease payments 434 2,724 Less: future interest expense (30 ) (539 ) Lease liabilities $ 404 $ 2,185

Note K - Common Stock and War_2

Note K - Common Stock and Warrants (Tables)	12 Months Ended
	Dec. 31, 2019
Notes Tables
Schedule of Authorized Shares of Common Stock Reserved for Future Issuance [Table Text Block]	December 31, 2019 2018 Conversion of Deerfield Convertible Note 1,213,606 1,167,607 Conversion of 2021 Notes 175,336 4,481,182 Conversion of 2019 Notes not subject to the Deerfield Optional Conversion Feature 3,186,770 - Outstanding awards under equity incentive plans 5,192,222 3,704,755 Outstanding common stock warrants 2,423,077 2,527,763 Conversion of Series A Preferred Stock - 1,112,334 In exchange for the Deerfield Optional Conversion Feature* 26,439,015 - Possible future issuances under the Prior Purchase Agreement 9,553,046 - Possible future issuances under equity incentive plans 84,616 648,272 Total common shares reserved for future issuance 48,267,688 13,641,913
Schedule of Common Stock Outstanding Roll Forward [Table Text Block]	Shares of Common Stock Balance as of January 1, 2018 14,657,430 Common stock sold under First ATM Agreement 762,338 Common stock issued as a result of Deerfield Convertible Note principal and interest conversion 598,568 Common stock options exercised 23,682 Common stock sold under underwritten public offering 8,333,334 Common stock issued as a result of Series A Preferred Stock conversion 2,080,000 Balance as of December 31, 2018 26,455,352 Common stock issued under the Prior Purchase Agreement 3,521,471 Restricted stock vested during the period 101,739 Common stock issued as a result of 2021 Notes principal conversion 1,499,894 Common stock issued as a result of Series B-1 Preferred Stock conversion 1,659,996 Common stock issued as a result of Series A Preferred Stock conversion 1,112,333 Common stock issued as a result of Deerfield Optional Conversion Feature conversion 2,000,000 Balance as of December 31, 2019 36,350,785

Note L - Stock-based Compensa_2

Note L - Stock-based Compensation (Tables)	12 Months Ended
	Dec. 31, 2019
Notes Tables
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]	Year ended December 31, 2019 2018 Research and development $ 1,459 $ 1,608 General and administrative 2,951 3,651 Severance expense - 1,236 Total stock-based compensation expense $ 4,410 $ 6,495
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]	Year Ended December 31, 2019 2018 Risk-free interest rate 1.75% 2.61% 2.43% 2.91% Expected term (in years) 5.50 10.00 5.50 6.79 Expected volatility 84.82% 85.93% 83.10% 85.05% Expected dividend yield 0% 0%
Share-based Payment Arrangement, Option, Activity [Table Text Block]	Weighted Weighted Avg Aggregate Number of Average Remaining Intrinsic Options Exercise Price Contractual Term Value Outstanding balance at January 1, 2019 3,704,755 $ 9.35 7.48 $ - Granted 2,291,820 $ 1.84 Exercised or released (101,739 ) $ - Canceled or forfeited (675,950 ) $ 8.80 Expired (26,664 ) $ 4.80 Outstanding balance at December 31, 2019 5,192,222 $ 6.31 7.63 $ - Exercisable at December 31, 2019 2,154,640 $ 10.80 6.04 $ - Vested and expected to vest at December 31, 2019 4,503,063 $ 7.16 7.30 $ -
Share-based Payment Arrangement, Option, Exercise Price Range [Table Text Block]	Options Outstanding Options Exercisable Weighted Avg Weighted Avg Number of Remaining Number of Remaining Exercise Price Shares Contractual Term Shares Contractual Term 0.52 to 5.00 2,902,995 8.72 479,039 7.19 5.01 to 10.00 1,102,844 6.74 599,969 5.62 10.01 to 15.00 471,833 5.94 381,208 5.90 15.01 to 20.00 379,550 5.70 359,424 5.67 20.01 to 20.45 335,000 5.68 335,000 5.68 5,192,222 7.63 2,154,640 6.04
Schedule of Nonvested Restricted Stock Units Activity [Table Text Block]	Number of Unvested Shares December 31, Exercise Price 2019 2018 $0.52 to $5.00 2,423,956 634,751 $5.01 to $10.00 502,875 818,900 $10.01 to $15.00 90,625 186,584 $15.01 to $20.00 20,126 139,988 $20.01 to $20.45 - 86,950 Total number of unvested stock options 3,037,582 1,867,173

Note M - Fair Value of Financ_2

Note M - Fair Value of Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2019
Notes Tables
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]	Quoted Prices Significant in Active Other Significant Balance at Markets for Observable Unobservable December 31, Identical Assets Inputs Inputs 2019 (Level 1) (Level 2) (Level 3) Deerfield Warrant liability $ 77 $ - $ - $ 77 Embedded Warrant Put Option 19 - - 19 Fundamental change and make-whole interest provisions embedded within 2021 Notes - - - - Deerfield Note Conversion Feature - - - - KVK Warrant liability 24 - 24 - Total liabilities $ 120 $ - $ 24 $ 96 Quoted Prices Significant in Active Other Significant Balance at Markets for Observable Unobservable December 31, Identical Assets Inputs Inputs 2018 (Level 1) (Level 2) (Level 3) Deerfield Warrant liability $ 1,557 $ - $ - $ 1,557 Embedded Warrant Put Option 154 - - 154 Fundamental change and make-whole interest provisions embedded within 2021 Notes - - - - Deerfield Note Conversion Feature 134 - - 134 KVK Warrant liability 273 - 273 - Total liabilities $ 2,118 $ - $ 273 $ 1,845 Trading securities: Certificates of deposit 246 246 - - U.S. Treasury securities 3,014 3,014 - - Total assets $ 3,260 $ 3,260 $ - $ -
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]	2019 2018 Balance as of beginning of period $ 1,845 $ 7,709 Gain on extinguishment of debt - (2 ) Adjustment to fair value (1,749 ) (5,862 ) Balance as of end of period $ 96 $ 1,845

Note N - Income Taxes (Tables)

Note N - Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2019
Notes Tables
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]	Year ended December 31, 2019 2018 Federal statutory rate 21.00 21.00 Effect of: Change in valuation allowance (28.52 ) (30.44 ) Return to provision and deferred true-up - 0.38 Change in rate (0.33 ) 0.03 State tax benefit (net of federal) 3.39 4.35 Warrant liability 1.71 2.02 State research and development credit 0.09 0.22 Federal research and development credit 1.44 3.30 Amortization (0.29 ) - Stock-based compensation (1.10 ) (0.63 ) Other 2.70 (0.01 ) Federal income tax provision effective rate 0.09 0.22
Schedule of Deferred Tax Assets and Liabilities [Table Text Block]	December 31, 2019 2018 Deferred tax assets relating to: Net operating loss carryforwards $ 56,827 $ 51,269 Research and development tax carryforward 6,411 5,657 Other deferred tax assets 4,488 3,437 Total gross deferred tax assets 67,726 60,363 Deferred tax liabilities relating to: Property and equipment - 161 Other deferred tax liabilities 540 10 Total gross deferred tax liabilities 540 171 Deferred tax assets less liabilities 67,186 60,192 Valuation allowance (67,186 ) (60,192 ) Net deferred tax asset (liability) $ - $ -
Summary of Operating Loss Carryforwards [Table Text Block]	Net Operating Research Year Incurred Loss CF Activities Cr. Expiration 2007 $ 454 $ 30 2027 2008 1,178 65 2028 2009 3,060 176 2029 2010 3,423 149 2030 2011 9,929 176 2031 2012 - 170 2032 2013 4,353 133 2033 2014 15,897 894 2034 2015 23,496 598 2035 2016 41,580 745 2036 2017 34,776 652 2037 2018 56,155 2,272 Indefinite 2019 22,784 352 Indefinite $ 217,085 $ 6,412

Note O - Net Loss Per Share (Ta

Note O - Net Loss Per Share (Tables)	12 Months Ended
	Dec. 31, 2019
Notes Tables
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]	Year Ended December 31, 2019 2018 Net loss - basic and diluted $ (24,522 ) $ (56,466 ) Weighted average number of shares of common stock - basic and diluted 29,654,968 17,930,023 Net loss per share - basic and diluted $ (0.83 ) $ (3.15 )
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]	December 31, 2019 2018 Deerfield Convertible Note 1,213,606 1,167,607 2021 Notes 175,336 4,481,182 2019 Notes* 29,625,785 - Awards under equity incentive plans 5,192,222 3,704,755 Common stock warrants 2,423,077 2,527,763 Series A Convertible Preferred Stock - 1,112,334 Total securities excluded from the calculation of weighted average number of shares of common stock outstanding 38,630,026 12,993,641

Note A - Description of Busin_2

Note A - Description of Business and Basis of Presentation (Details Textual) - USD ($)	Sep. 03, 2019	Feb. 28, 2019	Oct. 10, 2018	Oct. 05, 2018	Feb. 28, 2020	Oct. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Sep. 04, 2018	Oct. 31, 2019	Mar. 31, 2019
Sale of Securities, Value, Available to Issue							$ 150,000,000			$ 80,000,000
Sale of Securities, Value, Remaining Available to Issue							10,900,000
Sale of Securities Covered Under Prospectus Supplement, Value, Anticipated Sales Under Purchase Agreement							4,000,000	$ 5,700,000
Proceeds from Issuance of Common Stock								4,828,000
Revenue from Contract with Customer, Including Assessed Tax							12,839,000	$ 0
License [Member]
Revenue from Contract with Customer, Including Assessed Tax							$ 10,000,000
Cowen and Company, LLC [Member]
Stock Issued During Period, Shares, New Issues									762,338
Proceeds from Issuance of Common Stock									$ 4,900,000
Sale of Stock, Commission Fee									3.00%
RBC Capital Markets, LLC [Member]
Sale of Stock, Authorized Offering Price									$ 50,000,000		$ 3,200,000
Lincoln Park [Member]
Sale of Securities, Value, Available to Issue		$ 15,000,000
Stock Issued During Period, Shares, New Issues							3,401,271
Proceeds from Issuance of Common Stock							$ 5,400,000
Purchase Agreement, Term		3 years
Purchase Agreement, Additional Shares to Be Issued as Commitment Shares		120,200
Lincoln Park [Member] | Subsequent Event [Member]
Sale of Securities, Value, Available to Issue					$ 4,000,000
Purchase Agreement, Term					1 year
Purchase Agreement, Additional Shares to Be Issued as Commitment Shares					308,637
KVK [Member]
License Agreement, Estimated Pre-launch Payments and Costs Reimbursements						$ 3,400,000
License Agreement, Pre-launch Payment Reimbursement Within 10 Days of Initial Adoption Milestone						2,000,000
License Agreement, Maximum Payments Received for Sales Milestones						$ 53,000,000
KVK [Member] | Maximum [Member]
License Agreement, Percentage of Net Sales on Rolling Four Quarter Basis Received						50.00%
KVK [Member] | Minimum [Member]
License Agreement, Percentage of Net Sales on Rolling Four Quarter Basis Received						30.00%
GPC Member | License [Member]
Revenue from Contract with Customer, Including Assessed Tax	$ 10,000,000
Revenue Recognition, Milestone Method, Revenue to be Recognized	63,000,000
Revenue Recognition, Milestone Method, Additional Revenue to be Recognized	$ 420,000,000
Royalty Revenue, Percent	10.00%
First ATM Agreement [Member]
Stock Issued During Period, Shares, New Issues							3,401,271	762,338
Proceeds from Issuance of Common Stock							$ 5,400,000
Second ATM Agreement [Member]
Stock Issued During Period, Shares, New Issues							0
Second ATM Agreement [Member] | RBC Capital Markets, LLC [Member] | Maximum [Member]
Sale of Stock, Authorized Offering Price									$ 50,000,000
Underwriting Agreement [Member] | RBC Capital Markets, LLC [Member]
Stock Issued During Period, Shares, New Issues			8,333,334	8,333,334
Shares Issued, Price Per Share			$ 3
Proceeds from Issuance of Common Stock, Net			$ 23,100,000

Note B - Summary of Significa_2

Note B - Summary of Significant Accounting Policies (Details Textual) - USD ($)	Sep. 03, 2019	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2019
Prepaid Expense and Other Assets, Current		$ 1,552,000	$ 1,912,000
Increase (Decrease) in Prepaid Expense and Other Assets, Total		(544,000)	548,000
Asset Impairment Charges, Total		0	0
Revenue from Contract with Customer, Including Assessed Tax		12,839,000	0
Accounts Receivable, after Allowance for Credit Loss, Current, Total		1,681,000	0
Cost of Goods and Services Sold, Total		10,000,000	0
Capitalized Contract Cost, Gross		2,800,000
Deferred Revenue, Total		0	0
Accounts Receivable, Allowance for Credit Loss, Ending Balance		0	0
Income Tax Examination, Penalties and Interest Accrued, Total		$ 0	0
Open Tax Year		2014 2015 2016 2017 2018 2019
Operating Lease, Liability, Total		$ 2,185,000
Operating Lease, Right-of-Use Asset		1,537,000
Accounting Standards Update 2016-02 [Member]
Operating Lease, Liability, Total				$ 2,600,000
Operating Lease, Right-of-Use Asset				$ 2,600,000
Royalty and Direct Contract Acquisition Costs [Member]
Capitalized Contract Cost, Amortization		1,900,000
License [Member]
Revenue from Contract with Customer, Including Assessed Tax		10,000,000
Reimbursement of Out-of-pocket Third-party Research and Development Costs [Member]
Revenue from Contract with Customer, Including Assessed Tax		1,100,000
Accounts Receivable, after Allowance for Credit Loss, Current, Total		200,000
Consulting Services [Member]
Revenue from Contract with Customer, Including Assessed Tax		1,700,000
Accounts Receivable, after Allowance for Credit Loss, Current, Total		$ 1,400,000
GPC Member | License [Member]
Revenue from Contract with Customer, Including Assessed Tax	$ 10,000,000
Revenue Recognition, Milestone Method, Revenue to be Recognized	63,000,000
Revenue Recognition, Milestone Method, Additional Revenue to be Recognized	$ 420,000,000
Minimum [Member]
Property, Plant and Equipment, Useful Life		3 years
Maximum [Member]
Property, Plant and Equipment, Useful Life		10 years
Restatement Adjustment [Member]
Prepaid Expense and Other Assets, Current			(100,000)
Increase (Decrease) in Prepaid Expense and Other Assets, Total			$ (100,000)

Note C - Accounts and Other R_3

Note C - Accounts and Other Receivables - Accounts and Other Receivables (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accounts receivable	$ 1,681	$ 0
Other receivables	184	140
Total accounts and other receivables	$ 1,865	$ 140

Note D - Prepaid Expenses and_3

Note D - Prepaid Expenses and Other Current Assets - Components of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Prepaid insurance	$ 250	$ 224
Deferred direct contract acquisition costs	805
Prepaid offering costs	266
Other prepaid expenses and current assets	231	1,688
Total prepaid expenses and other current assets	$ 1,552	$ 1,912

Note E - Property and Equipme_3

Note E - Property and Equipment (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Depreciation, Depletion and Amortization, Total	$ 304,000	$ 324,000

Note E - Property and Equipme_4

Note E - Property and Equipment - Components of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property and equipment, gross	$ 3,031	$ 3,006
Less: accumulated depreciation and amortization	(1,560)	(1,253)
Property and equipment, net	1,471	1,753
Laboratory Equipment [Member]
Property and equipment, gross	638	1,035
Furniture and Fixtures [Member]
Property and equipment, gross	119	655
Computer and Hardware [Member]
Property and equipment, gross	303	299
Leasehold Improvements [Member]
Property and equipment, gross	958	1,017
Finance Lease, Right-of-Use Assets [Member]
Property and equipment, gross	$ 1,013

Note E - Property and Equipme_5

Note E - Property and Equipment - Estimated Useful Lives of Property and Equipment (Details)	12 Months Ended
	Dec. 31, 2019
Minimum [Member]
Property and equipment, useful lives (Year)	3 years
Maximum [Member]
Property and equipment, useful lives (Year)	10 years
Laboratory Equipment [Member]
Property and equipment, useful lives (Year)	10 years
Furniture and Fixtures [Member] | Minimum [Member]
Property and equipment, useful lives (Year)	5 years
Furniture and Fixtures [Member] | Maximum [Member]
Property and equipment, useful lives (Year)	10 years
Computer and Hardware [Member] | Minimum [Member]
Property and equipment, useful lives (Year)	3 years
Computer and Hardware [Member] | Maximum [Member]
Property and equipment, useful lives (Year)	7 years
Leasehold Improvements [Member]
Property and equipment, useful lives (Year)	9 years

Note F - Accounts Payable and_3

Note F - Accounts Payable and Accrued Expenses - Accounts Payable and Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accrued interest	$ 359	$ 1,921
Accrued banking fees	700	700
Accrued severance		193
Accrued payroll	1	731
Accrued professional fees	2,364	230
Accounts payable	1,140	3,715
Other accrued expenses	347	852
Total accounts payable and accrued expenses	$ 4,911	$ 8,342

Note G - Debt Obligations (Deta

Note G - Debt Obligations (Details Textual) - USD ($)	Jan. 13, 2020	Dec. 31, 2019	Dec. 18, 2019	Sep. 03, 2019	Oct. 05, 2018	Jun. 11, 2018	Feb. 09, 2016	Jun. 02, 2014	Apr. 30, 2015	Dec. 31, 2019	Sep. 03, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Sep. 02, 2019	Jun. 30, 2016
Convertible Notes Payable, Current													$ 3,333,000
Convertible Preferred Stock, Conversion Restriction, Percentage of Common Stock				4.985%							4.985%
Interest Paid, Excluding Capitalized Interest, Operating Activities												$ 5,362,000	$ 5,539,000
Conversion of Stock, Maximum Shares Issued			28,439,015
Series A Preferred Stock Converted Into Common Stock [Member]
Conversion of Stock, Shares Issued												1,112,333	2,080,000	3,192,333
Conversion of Stock, Shares Converted														9,577
Series B-1 Preferred Convertible Stock Converted to Common Stock [Member]
Conversion of Stock, Shares Issued										1,659,966		1,659,996
Conversion of Stock, Shares Converted										1,576		1,576
Series A Preferred Stock [Member]
Preferred Stock, Par or Stated Value Per Share					$ 0.0001
Preferred Stock, Aggregate Stated Value Per Share					1,000
Convertible Preferred Stock, Conversion Price					$ 3
Convertible Preferred Stock, Shares Issuable Upon Conversion					3,192,333
Conversion Of Stock Shares Issuable If Converted					3,192,333
Preferred Stock, Shares Outstanding, Ending Balance		0								0		0	3,337	0
Series B-1 Convertible Preferred Stock [Member]
Preferred Stock, Par or Stated Value Per Share		$ 0.0001		$ 0.0001						$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001
Preferred Stock, Aggregate Stated Value Per Share				1,000							1,000
Convertible Preferred Stock, Conversion Price				$ 0.9494							$ 0.9494
Conversion Of Stock Shares Issuable If Converted				1,659,996							1,659,996
Convertible Preferred Stock, Conversion Restriction, Percentage of Common Stock				4.985%							4.985%
Preferred Stock, Liquidation Preference Per Share				$ 0.0001							$ 0.0001
Preferred Stock, Shares Outstanding, Ending Balance		0								0		0	0	0
Series B-2 Convertible Preferred Stock [Member]
Preferred Stock, Par or Stated Value Per Share		$ 0.0001		0.0001						$ 0.0001	0.0001	$ 0.0001	$ 0.0001	$ 0.0001
Preferred Stock, Aggregate Stated Value Per Share				1,000							1,000
Convertible Preferred Stock, Conversion Price				$ 0.9494							$ 0.9494
Conversion Of Stock Shares Issuable If Converted				28,439,015							28,439,015
Preferred Stock, Shares Outstanding, Ending Balance		0								0		0	0	0
Series B Preferred Stock [Member]
Preferred Stock, Liquidation Preference Per Share				$ 0.0001							$ 0.0001
Conversion from Deerfield Convertible Note to Common Stock [Member]
Debt Conversion, Original Debt, Amount						$ 3,333,333
Debt Conversion, Accrued Interest						$ 168,288
Debt Conversion, Converted Instrument, Shares Issued						598,568
Exchanged 2021 Notes for Series A Preferred Stock [Member]
Debt Conversion, Original Debt, Amount					$ 9,577,000
Debt Conversion, Converted Instrument, Shares Issued					9,577
DebtConversionOptionToExchangeAmount				$ 27,000,000							$ 27,000,000
2021NotesConvertedToCommonStockMember
Debt Conversion, Converted Instrument, Shares Issued				1,499,894
2021NotesConvertedToSeriesB1PreferredStockMember
Debt Conversion, Converted Instrument, Shares Issued				1,576
Conversion From Deerfield Convertible Note to Common and Preferred Stock Member
Debt Conversion, Original Debt, Amount				$ 3,000,000
Exchanged2021NotesForSeriesB2PreferredStockMember
Debt Instrument, Convertible, Conversion Price				$ 1,000							$ 1,000
Exchanged2021NotesForCommonStockMember
Debt Instrument, Convertible, Conversion Price				$ 0.9494							$ 0.9494
The 2019 Notes Converted to Common Stock [Member]
Debt Conversion, Original Debt, Amount		$ 1,200,000										$ 1,200,000
Debt Conversion, Converted Instrument, Shares Issued		2,000,000
2021 Notes [Member]
Debt Instrument, Convertible, Conversion Price							$ 17.11
Debt Conversion, Original Debt, Amount							$ 1,000
Debt Conversion, Converted Instrument, Shares Issued							58.4454
Debt Instrument, Interest Rate, Stated Percentage							5.50%
Debt Instrument, Face Amount							$ 86,300,000
Debt Instrument, Sinking Fund Payment							0
Proceeds from Debt, Net of Issuance Costs							82,800,000
Repayments of Long-term Debt, Total							$ 18,600,000
Debt Instrument Repurchase Price Equal to Percentage of Principal Amount							100.00%
Debt Instrument, Cancellation of Debt, Amount			$ 71,418,011
Interest Paid, Excluding Capitalized Interest, Operating Activities			$ 745,011
Debt Instrument, Percentage of Accrued Interest Paid			50.00%
2021 Notes [Member] | Subsequent Event [Member]
Debt Instrument, Cancellation of Debt, Amount	$ 3,037,354
Interest Paid, Excluding Capitalized Interest, Operating Activities	$ 37,354
The 2019 Notes [Member]
Debt Instrument, Convertible, Conversion Price			$ 17.11
Debt Instrument, Interest Rate, Stated Percentage			6.75%
Debt Instrument, Face Amount			$ 71,418,011
Debt Instrument, Convertible, Number of Equity Instruments			4,174,051
Debt Instrument, Convertible, Minimum Conversion Price		$ 0.38	$ 0.583							$ 0.38		$ 0.38		$ 0.38
Debt Instrument, Convertible, Conversion Restriction Percentage of Common Stock			4.985%
Beneficial Ownership, Cap Limit, Percentage			19.985%
The 2019 Notes [Member] | Subsequent Event [Member]
Debt Instrument, Convertible, Conversion Price	$ 5.85
Debt Instrument, Percentage of Accrued Interest Paid	50.00%
Debt Instrument, Convertible, Minimum Conversion Price	$ 0.583
January 2020 Notes [Member] | Subsequent Event [Member]
Debt Instrument, Face Amount	$ 3,037,354
Deerfield Facility Agreement [Member]
Line of Credit Facility, Maximum Borrowing Capacity								$ 60,000,000
Debt Instrument, Convertible, Conversion Price			$ 5.85
Line of Credit Facility, Interest Rate at Period End				6.75%				9.75%			6.75%					6.75%
Debt Instrument, Interest Rate, Stated Percentage		6.75%								6.75%		6.75%		6.75%	9.75%
Convertible Notes Payable, Current		$ 6,980,824								$ 6,980,824		$ 6,980,824		$ 6,980,824
Debt Covenant, Debt Financing Restriction								$ 750,000
Reimbursement of Debt Holders				$ 150,000							$ 150,000
Change in Fair Value of Embedded Conversion Feature											$ 2,300,000
Debt Instrument, Convertible, Minimum Conversion Price			$ 0.60
Deerfield Facility Agreement [Member] | Deerfield Warrant [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights								$ 0.78
Deerfield Facility Agreement [Member] | Deerfield Warrant [Member] | IPO [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights								1,923,077
Deerfield Facility Agreement [Member] | Series D Redeemable Convertible Preferred Stock Reclassified to Common Stock [Member]
Conversion of Stock, Shares Issued									256,410
Deerfield Facility Agreement [Member] | Series D Redeemable Convertible Preferred Stock [Member]
Own-share Lending Arrangement, Shares, Issued								1,923,077
Class of Warrant or Right, Number of Securities Called by Warrants or Rights								14,423,076
Deerfield Facility Agreement [Member] | Term Notes [Member]
Proceeds from Secured Notes Payable								$ 15,000,000
Deerfield Facility Agreement [Member] | Deerfield Convertible Notes [Member]
Proceeds from Secured Notes Payable								$ 10,000,000
Debt Instrument, Convertible, Conversion Price								$ 5.85

Note G - Debt Obligations - Con

Note G - Debt Obligations - Convertible Notes Outstanding (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Convertible notes	$ 80,199	$ 83,340
Less: debt issuance costs and discounts	(2,856)	(1,902)
Convertible notes, net	77,343	81,438
Deerfield Convertible Notes [Member]
Convertible notes	6,981	6,667
2021 Notes [Member]
Convertible notes	3,000	76,673
The 2019 Notes [Member]
Convertible notes	$ 70,218

Note G - Debt Obligations - Fut

Note G - Debt Obligations - Future Minimum Payments (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
2020
2021	80,199
Total minimum principal payments	80,199	$ 83,340
Less: debt issuance costs and discounts	(2,856)	(1,902)
Convertible notes, net	$ 77,343	$ 81,438

Note H - Commitments and Cont_3

Note H - Commitments and Contingencies (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Loss Contingency Accrual, Ending Balance	$ 0	$ 0
Lessee, Lease, Option to Extend, Maximum Term	5 years
Lessee, Lease, Option to Terminate, Term	1 year
Operating and Capital Leases, Rent Expense, Net	$ 700	$ 700
Minimum [Member]
Lessee, Lease, Remaining Term of Contract	1 year
Capital Lease, Interest Rate	7.19%	7.19%
Maximum [Member]
Lessee, Lease, Remaining Term of Contract	6 years
Capital Lease, Interest Rate	9.57%	9.57%

Note H - Commitments and Cont_4

Note H - Commitments and Contingencies - Lease Cost (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)
Amortization of right-of-use assets	$ 123
Interest on lease liabilities	40
Total finance lease cost	163
Operating lease cost	473
Short-term lease cost	232
Variable lease cost	48
Less: sublease income	(84)
Total lease costs	$ 832

Note H - Commitments and Cont_5

Note H - Commitments and Contingencies - Supplement Cash Flow Information Related to Leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Operating cash flows from finance leases	$ 40
Financing cash flows from finance leases	207
Operating cash flows from operating leases	435
Operating cash flows from short-term leases	232
Operating cash flows from variable lease costs	48
Finance leases	757
Operating leases	$ 1,852

Note H - Commitments and Cont_6

Note H - Commitments and Contingencies - Supplement Balance Sheet Information Related to Lease (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
less: accumulated depreciation and amortization	$ (1,560)	$ (1,253)
Lease liabilities	404
Operating lease right-of-use assets	1,537
Operating Lease, Right-of-Use Asset	1,537
Current portion of operating lease liabilities	284
Operating lease liabilities, less current portion	1,901
Total operating lease liabilities	$ 2,185
Finance leases (Year)	2 years
Operating leases (Year)	6 years
Finance leases	7.70%
Operating leases	7.50%
Property and Equipment, At Cost [Member]
Property and equipment, at cost	$ 1,013
Accumulated Depreciation and Amortization [Member]
less: accumulated depreciation and amortization	(398)
Property and Equipment, Net [Member]
Property and equipment, net	615
Other Current Liabilities [Member]
Other current liabilities	236
Other Noncurrent Liabilities [Member]
Other long-term liabilities	168
Operating Lease Right-of-Use Assets [Member]
Operating lease right-of-use assets	1,537
Operating Lease, Right-of-Use Asset	1,537
Current Portion of Operating Lease Liabilities [Member]
Current portion of operating lease liabilities	284
Operating Lease Liabilities, Less Current Portion [Member]
Operating lease liabilities, less current portion	$ 1,901

Note H - Commitments and Cont_7

Note H - Commitments and Contingencies - Maturities of lease Liabilities (Details) $ in Thousands	Dec. 31, 2019USD ($)
2020	$ 260
2020	438
2021	163
2021	449
2022	11
2022	461
2023
2023	472
2024
2024	484
Thereafter
Thereafter	420
Total lease payments	434
Total lease payments	2,724
Less: future interest expense	(30)
Less: future interest expense	(539)
Lease liabilities	404
Operating Lease, Liability, Total	$ 2,185

Note I - Supply Arrangement (De

Note I - Supply Arrangement (Details Textual) $ in Millions	12 Months Ended
	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Number of Manufacturing Arrangements	1	1
Supply Arrangement Expense	$ 3.2	$ 3.6
Supply Arrangement, Automatic Renewal Period	2 years
Supply Arrangement, Period of Prior Notice	1 year

Note J - Preferred Stock and _2

Note J - Preferred Stock and Warrants (Details Textual) - $ / shares	Oct. 05, 2018	Dec. 31, 2019	Dec. 31, 2019	Sep. 03, 2019	Dec. 31, 2018
Preferred Stock, Shares Authorized		10,000,000	10,000,000
Convertible Preferred Stock, Conversion Restriction, Percentage of Common Stock				4.985%
Series B-1 Preferred Convertible Stock Converted to Common Stock [Member]
Conversion of Stock, Shares Converted		1,576	1,576
Conversion of Stock, Shares Issued		1,659,966	1,659,996
Series A Preferred Stock [Member]
Preferred Stock, Shares Authorized		9,578	9,578
Preferred Stock, Shares Issued, Total		9,577	9,577		9,577
Preferred Stock, Shares Outstanding, Ending Balance		0	0		3,337
Preferred Stock, Aggregate Stated Value Per Share	$ 1,000
Convertible Preferred Stock, Conversion Price	$ 3
Conversion Of Stock Shares Issuable If Converted	3,192,333
Series B-1 Convertible Preferred Stock [Member]
Preferred Stock, Shares Authorized		1,576	1,576		0
Preferred Stock, Shares Issued, Total		1,576	1,576		0
Preferred Stock, Shares Outstanding, Ending Balance		0	0		0
Preferred Stock, Aggregate Stated Value Per Share				$ 1,000
Convertible Preferred Stock, Conversion Price				$ 0.9494
Conversion Of Stock Shares Issuable If Converted				1,659,996
Convertible Preferred Stock, Conversion Restriction, Percentage of Common Stock				4.985%
Preferred Stock, Liquidation Preference Per Share				$ 0.0001
Series B-2 Convertible Preferred Stock [Member]
Preferred Stock, Shares Authorized		27,000	27,000		0
Preferred Stock, Shares Issued, Total		0	0		0
Preferred Stock, Shares Outstanding, Ending Balance		0	0		0
Preferred Stock, Aggregate Stated Value Per Share				1,000
Convertible Preferred Stock, Conversion Price				$ 0.9494
Conversion Of Stock Shares Issuable If Converted				28,439,015
Preferred Class A [Member]
Debt Conversion, Converted Instrument, Shares Issued	9,577
Preferred Stock, Aggregate Stated Value Per Share	$ 1,000

Note K - Common Stock and War_3

Note K - Common Stock and Warrants (Details Textual) - USD ($)	Sep. 03, 2019	Oct. 25, 2018	Oct. 10, 2018	Oct. 05, 2018	Jun. 02, 2014	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2013	Dec. 31, 2019	Sep. 04, 2018	Dec. 31, 2017
Common Stock, Shares Authorized						250,000,000	250,000,000	250,000,000		250,000,000
Common Stock, Shares, Issued, Total						36,350,785	36,350,785	26,455,352		36,350,785
Proceeds from Issuance of Common Stock								$ 4,828,000
Stock Issued During Period, Shares, Conversion of Convertible Securities								598,568
Common Stock, Shares, Outstanding, Ending Balance						36,350,785	36,350,785	26,455,352		36,350,785		14,657,430
Common Stock [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights									143,466
Class of Warrant or Right, Exercise Price of Warrants or Rights									$ 5.85
2013 Warrants [Member]
Debt Instrument, Face Amount									$ 3,800,000
Class of Warrant or Right Issued									1,079,453
Series D Redeemable Convertible Preferred Stock [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights									1,079,453
Deerfield Warrant [Member]
Class of Warrant or Right Issued					14,423,076
Deerfield Warrant [Member] | Common Stock [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights					1,923,077
Class of Warrant or Right, Exercise Price of Warrants or Rights					$ 5.85
Warrant Issued to KVK [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights		500,000
Class of Warrant or Right, Exercise Price of Warrants or Rights		$ 2.30
Class of Warrant or Right, Additional Shares Exercisable for Each Milestones		125,000
Series A Preferred Stock Converted Into Common Stock [Member]
Conversion of Stock, Shares Converted										9,577
Conversion of Stock, Shares Issued							1,112,333	2,080,000		3,192,333
2021NotesConvertedToCommonStockMember
Stock Issued During Period, Shares, Conversion of Convertible Securities	1,499,894
2021NotesConvertedToSeriesB1PreferredStockMember
Stock Issued During Period, Shares, Conversion of Convertible Securities	1,576
Series B-1 Preferred Convertible Stock Converted to Common Stock [Member]
Conversion of Stock, Shares Converted						1,576	1,576
Conversion of Stock, Shares Issued						1,659,966	1,659,996
Exchanged 2021 Notes for Series A Preferred Stock [Member]
Debt Conversion, Converted Instrument, Shares Issued				9,577
Second ATM Agreement [Member]
Stock Issued During Period, Shares, New Issues							0
Cowen and Company, LLC [Member]
Stock Issued During Period, Shares, New Issues											762,338
Proceeds from Issuance of Common Stock											$ 4,900,000
RBC Capital Markets, LLC [Member] | Underwriting Agreement [Member]
Stock Issued During Period, Shares, New Issues			8,333,334	8,333,334

Note K - Common Stock and War_4

Note K - Common Stock and Warrants - Reserved Authorized Shares of Common Stock for Future Issuance (Details) - shares	Dec. 31, 2019	Dec. 31, 2018
Common shares reserved for future issuance (in shares)	48,267,688	13,641,913
Series A Preferred Stock [Member]
Common shares reserved for future issuance (in shares)		1,112,334
Warrant [Member]
Common shares reserved for future issuance (in shares)	2,423,077	2,527,763
Share-based Payment Arrangement [Member]
Common shares reserved for future issuance (in shares)	5,192,222	3,704,755
Possible Future Issuances under the Prior Purchase Agreement [Member]
Common shares reserved for future issuance (in shares)	9,553,046
Possible Future Issuances Under Equity Incentive Plans [Member]
Common shares reserved for future issuance (in shares)	84,616	648,272
2021 Notes [Member]
Common shares reserved for future issuance (in shares)	175,336	4,481,182
The 2019 Notes [Member]
Common shares reserved for future issuance (in shares)	3,186,770
Optional Exchange Principal Amount [Member]
Common shares reserved for future issuance (in shares)	26,439,015
Convertible Notes Payable [Member]
Common shares reserved for future issuance (in shares)	1,213,606	1,167,607

Note K - Common Stock and War_5

Note K - Common Stock and Warrants - Common Stock Activity (Details) - shares	4 Months Ended	12 Months Ended		15 Months Ended
	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019
Balance (in shares)		26,455,352	14,657,430
Common stock issued as a result of Convertible Note conversion (in shares)			598,568
Common stock options exercised (in shares)		101,739	23,682
Restricted stock vested during the period (in shares)		101,739
Balance (in shares)	36,350,785	36,350,785	26,455,352	36,350,785
2021NotesConvertedToCommonStockMember
Common stock issued as a result of Convertible Note conversion (in shares)		1,499,894
Optional Exchange Principal Amount [Member]
Common stock issued as a result of Convertible Note conversion (in shares)		2,000,000
Equity Line of Credit [Member]
Common stock sold (in shares)		3,521,471
Series A Preferred Stock Converted Into Common Stock [Member]
Common stock issued as a result of Preferred Stock conversion (in shares)		1,112,333	2,080,000	3,192,333
Series B-1 Preferred Convertible Stock Converted to Common Stock [Member]
Common stock issued as a result of Preferred Stock conversion (in shares)	1,659,966	1,659,996
First ATM Agreement [Member]
Common stock sold (in shares)		3,401,271	762,338
Underwriting Public Offering [Member]
Common stock sold (in shares)			8,333,334

Note L - Stock-based Compensa_3

Note L - Stock-based Compensation (Details Textual) - USD ($)	Jan. 01, 2020	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures, Total				101,739
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period				101,739	23,682
Stock Issued During Period, Value, Stock Options Exercised					$ 68,000
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate				0.00%	0.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value				$ 1.43	$ 4.05
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value				$ 4,900,000	$ 5,900,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total				$ 3,800,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition				2 years 105 days
Share-based Payment Arrangement, Expense				$ 4,410,000	6,495,000
Performance Shares [Member]
Share-based Payment Arrangement, Expense				$ 0	$ 0
2014 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized				5,076,694
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Reserved for Issuance, Incremental Percentage of Capital Stock Outstanding				4.00%
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures, Total		39,284	42,436	20,019
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period				0	23,682
Stock Issued During Period, Value, Stock Options Exercised					$ 68,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value					$ 69,000
2014 Equity Incentive Plan [Member] | Subsequent Event [Member]
Increase in Common Stock Reserved for Issuance	1,454,031

Note L - Stock-based Compensa_4

Note L - Stock-based Compensation - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Stock based compensation expense	$ 4,410	$ 6,495
Research and Development Expense [Member]
Stock based compensation expense	1,459	1,608
General and Administrative Expense [Member]
Stock based compensation expense	2,951	3,651
Severance Expense [Member]
Stock based compensation expense		$ 1,236

Note L - Stock-based Compensa_5

Note L - Stock-based Compensation - Black-Scholes Option-pricing Model (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Expected dividend yield	0.00%	0.00%
Minimum [Member]
Risk-free interest rate	1.75%	2.43%
Expected term (in years) (Year)	5 years 182 days	5 years 182 days
Expected volatility	84.82%	83.10%
Maximum [Member]
Risk-free interest rate	2.61%	2.91%
Expected term (in years) (Year)	10 years	6 years 288 days
Expected volatility	85.93%	85.05%

Note L - Stock-based Compensa_6

Note L - Stock-based Compensation - Schedule of Stock Option Activity (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Outstanding, number of options (in shares)	3,704,755
Outstanding, weighted average exercise price (in dollars per share)	$ 9.35
Outstanding, weighted average remaining contractual term (Year)	7 years 229 days	7 years 175 days
Outstanding, aggregate intrinsic value
Granted, number of options (in shares)	2,291,820
Granted, weighted average exercise price (in dollars per share)	$ 1.84
Exercised or released, number of options (in shares)	(101,739)	(23,682)
Exercised or released, weighted average exercise price (in dollars per share)
Canceled or forfeited, number of options (in shares)	(675,950)
Canceled or forfeited, weighted average exercise price (in dollars per share)	$ 8.80
Expired, number of options (in shares)	(26,664)
Expired, weighted average exercise price (in dollars per share)	$ 4.80
Outstanding, number of options (in shares)	5,192,222	3,704,755
Outstanding, weighted average exercise price (in dollars per share)	$ 6.31	$ 9.35
Exercisable, number of options (in shares)	2,154,640
Exercisable, weighted average exercise price (in dollars per share)	$ 10.80
Exercisable, weighted average remaining contractual term (Year)	6 years 14 days
Vested and expected to vest, number of options (in shares)	4,503,063
Vested and expected to vest, weighted average exercise price (in dollars per share)	$ 7.16
Vested and expected to vest, weighted average remaining contractual term (Year)	7 years 109 days

Note L - Stock-based Compensa_7

Note L - Stock-based Compensation - Information Regarding Currently Outstanding and Exercisable Options (Details) - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Lower range (in dollars per share)	$ 0.52
Upper range (in dollars per share)	$ 5
Options outstanding, number of shares (in shares)	5,192,222	3,704,755
Outstanding, weighted average remaining contractual term (Year)	7 years 229 days	7 years 175 days
Exercisable, number of options (in shares)	2,154,640
Exercisable, weighted average remaining contractual term (Year)	6 years 14 days
Exercise Price Range One [Member]
Lower range (in dollars per share)	$ 0.52
Upper range (in dollars per share)	$ 5
Options outstanding, number of shares (in shares)	2,902,995
Outstanding, weighted average remaining contractual term (Year)	8 years 262 days
Exercisable, number of options (in shares)	479,039
Exercisable, weighted average remaining contractual term (Year)	7 years 69 days
Exercise Price Range Two [Member]
Lower range (in dollars per share)	$ 5.01
Upper range (in dollars per share)	$ 10
Options outstanding, number of shares (in shares)	1,102,844
Outstanding, weighted average remaining contractual term (Year)	6 years 270 days
Exercisable, number of options (in shares)	599,969
Exercisable, weighted average remaining contractual term (Year)	5 years 226 days
Exercise Price Range Three [Member]
Lower range (in dollars per share)	$ 10.01
Upper range (in dollars per share)	$ 15
Options outstanding, number of shares (in shares)	471,833
Outstanding, weighted average remaining contractual term (Year)	5 years 343 days
Exercisable, number of options (in shares)	381,208
Exercisable, weighted average remaining contractual term (Year)	5 years 328 days
Exercise Price Range Four [Member]
Lower range (in dollars per share)	$ 15.01
Upper range (in dollars per share)	$ 20
Options outstanding, number of shares (in shares)	379,550
Outstanding, weighted average remaining contractual term (Year)	5 years 255 days
Exercisable, number of options (in shares)	359,424
Exercisable, weighted average remaining contractual term (Year)	5 years 244 days
Exercise Price Range Five [Member]
Lower range (in dollars per share)	$ 20.01
Upper range (in dollars per share)	$ 20.45
Options outstanding, number of shares (in shares)	335,000
Outstanding, weighted average remaining contractual term (Year)	5 years 248 days
Exercisable, number of options (in shares)	335,000
Exercisable, weighted average remaining contractual term (Year)	5 years 248 days

Note L - Stock-based Compensa_8

Note L - Stock-based Compensation - Nonvested Stock Option Awards (Details) - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Lower range (in dollars per share)	$ 0.52
Upper range (in dollars per share)	$ 5
Number of unvested shares (in shares)	3,037,582	1,867,173
Exercise Price Range One [Member]
Lower range (in dollars per share)	$ 0.52
Upper range (in dollars per share)	$ 5
Exercise Price Range One [Member] | Minimum [Member]
Number of unvested shares (in shares)	2,423,956
Exercise Price Range One [Member] | Maximum [Member]
Number of unvested shares (in shares)		634,751
Exercise Price Range Two [Member]
Lower range (in dollars per share)	$ 5.01
Upper range (in dollars per share)	$ 10
Exercise Price Range Two [Member] | Minimum [Member]
Number of unvested shares (in shares)	502,875
Exercise Price Range Two [Member] | Maximum [Member]
Number of unvested shares (in shares)		818,900
Exercise Price Range Three [Member]
Lower range (in dollars per share)	$ 10.01
Upper range (in dollars per share)	$ 15
Exercise Price Range Three [Member] | Minimum [Member]
Number of unvested shares (in shares)	90,625
Exercise Price Range Three [Member] | Maximum [Member]
Number of unvested shares (in shares)		186,584
Exercise Price Range Four [Member]
Lower range (in dollars per share)	$ 15.01
Upper range (in dollars per share)	$ 20
Exercise Price Range Four [Member] | Minimum [Member]
Number of unvested shares (in shares)	20,126
Exercise Price Range Four [Member] | Maximum [Member]
Number of unvested shares (in shares)		139,988
Exercise Price Range Five [Member]
Lower range (in dollars per share)	$ 20.01
Upper range (in dollars per share)	$ 20.45
Exercise Price Range Five [Member] | Minimum [Member]
Number of unvested shares (in shares)
Exercise Price Range Five [Member] | Maximum [Member]
Number of unvested shares (in shares)		86,950

Note M - Fair Value of Financ_3

Note M - Fair Value of Financial Instruments (Details Textual) - Fair Value, Inputs, Level 3 [Member] - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
The 2019 Notes [Member]
Long-term Debt, Fair Value	$ 57
Deerfield Facility Agreement [Member] | Deerfield Convertible Notes [Member]
Long-term Debt, Fair Value	6	$ 6.2
Deerfield Facility Agreement [Member] | Term Notes [Member]
Long-term Debt, Fair Value	$ 2.4	$ 51.2

Note M - Fair Value of Financ_4

Note M - Fair Value of Financial Instruments - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - Fair Value, Recurring [Member] - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financial liabilities measured at fair value on recurring basis		$ 2,118
Financial assets measured at fair value on recurring basis		3,260
Certificates of Deposit [Member]
Financial assets measured at fair value on recurring basis		246
US Treasury Securities [Member]
Financial assets measured at fair value on recurring basis		3,014
Fair Value, Inputs, Level 1 [Member]
Financial liabilities measured at fair value on recurring basis
Financial assets measured at fair value on recurring basis		3,260
Fair Value, Inputs, Level 1 [Member] | Certificates of Deposit [Member]
Financial assets measured at fair value on recurring basis		246
Fair Value, Inputs, Level 1 [Member] | US Treasury Securities [Member]
Financial assets measured at fair value on recurring basis		3,014
Fair Value, Inputs, Level 2 [Member]
Financial liabilities measured at fair value on recurring basis		273
Financial assets measured at fair value on recurring basis
Fair Value, Inputs, Level 2 [Member] | Certificates of Deposit [Member]
Financial assets measured at fair value on recurring basis
Fair Value, Inputs, Level 2 [Member] | US Treasury Securities [Member]
Financial assets measured at fair value on recurring basis
Fair Value, Inputs, Level 3 [Member]
Financial liabilities measured at fair value on recurring basis		1,845
Financial assets measured at fair value on recurring basis
Fair Value, Inputs, Level 3 [Member] | Certificates of Deposit [Member]
Financial assets measured at fair value on recurring basis
Fair Value, Inputs, Level 3 [Member] | US Treasury Securities [Member]
Financial assets measured at fair value on recurring basis
Deerfield Warrant Liability [Member]
Financial liabilities measured at fair value on recurring basis	$ 77	1,557
Deerfield Warrant Liability [Member] | Fair Value, Inputs, Level 1 [Member]
Financial liabilities measured at fair value on recurring basis
Deerfield Warrant Liability [Member] | Fair Value, Inputs, Level 2 [Member]
Financial liabilities measured at fair value on recurring basis
Deerfield Warrant Liability [Member] | Fair Value, Inputs, Level 3 [Member]
Financial liabilities measured at fair value on recurring basis	77	1,557
Embedded Put Option [Member]
Financial liabilities measured at fair value on recurring basis	19	154
Embedded Put Option [Member] | Fair Value, Inputs, Level 1 [Member]
Financial liabilities measured at fair value on recurring basis
Embedded Put Option [Member] | Fair Value, Inputs, Level 2 [Member]
Financial liabilities measured at fair value on recurring basis
Embedded Put Option [Member] | Fair Value, Inputs, Level 3 [Member]
Financial liabilities measured at fair value on recurring basis	19	154
Fundamental Change and Make-Whole Interest Provisions Embedded in 2021 Notes [Member]
Financial liabilities measured at fair value on recurring basis
Fundamental Change and Make-Whole Interest Provisions Embedded in 2021 Notes [Member] | Fair Value, Inputs, Level 1 [Member]
Financial liabilities measured at fair value on recurring basis
Fundamental Change and Make-Whole Interest Provisions Embedded in 2021 Notes [Member] | Fair Value, Inputs, Level 2 [Member]
Financial liabilities measured at fair value on recurring basis
Fundamental Change and Make-Whole Interest Provisions Embedded in 2021 Notes [Member] | Fair Value, Inputs, Level 3 [Member]
Financial liabilities measured at fair value on recurring basis
Embedded Deerfield Note Put Option [Member]
Financial liabilities measured at fair value on recurring basis		134
Embedded Deerfield Note Put Option [Member] | Fair Value, Inputs, Level 1 [Member]
Financial liabilities measured at fair value on recurring basis
Embedded Deerfield Note Put Option [Member] | Fair Value, Inputs, Level 2 [Member]
Financial liabilities measured at fair value on recurring basis
Embedded Deerfield Note Put Option [Member] | Fair Value, Inputs, Level 3 [Member]
Financial liabilities measured at fair value on recurring basis		134
KVK Warrant Liability [Member]
Financial liabilities measured at fair value on recurring basis	24	273
KVK Warrant Liability [Member] | Fair Value, Inputs, Level 1 [Member]
Financial liabilities measured at fair value on recurring basis
KVK Warrant Liability [Member] | Fair Value, Inputs, Level 2 [Member]
Financial liabilities measured at fair value on recurring basis	24	273
KVK Warrant Liability [Member] | Fair Value, Inputs, Level 3 [Member]
Financial liabilities measured at fair value on recurring basis
Optional Exchange Principal Amount Conversion Feature [Member[
Financial liabilities measured at fair value on recurring basis	120
Optional Exchange Principal Amount Conversion Feature [Member[ | Fair Value, Inputs, Level 1 [Member]
Financial liabilities measured at fair value on recurring basis
Optional Exchange Principal Amount Conversion Feature [Member[ | Fair Value, Inputs, Level 2 [Member]
Financial liabilities measured at fair value on recurring basis	24
Optional Exchange Principal Amount Conversion Feature [Member[ | Fair Value, Inputs, Level 3 [Member]
Financial liabilities measured at fair value on recurring basis	$ 96

Note M - Fair Value of Financ_5

Note M - Fair Value of Financial Instruments - Reconciliation of Beginning and Ending Balances for Derivative and Warrant Liability Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Balance as of beginning of period	$ 1,845	$ 7,709
Gain on extinguishment of debt		(2)
Adjustment to fair value	(1,749)	(5,862)
Balance as of end of period	$ 96	$ 1,845

Note N - Income Taxes (Details

Note N - Income Taxes (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
State and Local Income Tax Expense (Benefit), Continuing Operations, Total	$ 22,000	$ (126,000)
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest, Total	(24,544,000)	$ (56,592,000)
Operating Loss Carryforwards, Total	217,085,000
State and Local Jurisdiction [Member]
Operating Loss Carryforwards, Total	$ 136,000,000
Operating Loss Carryforwards, Expiration, Beginning Year	2027
Operating Loss Carryforwards, Expiration, Ending Year	2037

Note N - Income Taxes - Schedul

Note N - Income Taxes - Schedule of Reconciliation of Difference Between Benefit for Income Taxes and Income Taxes at Statutory U.S. Federal Income Tax Rate (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Federal statutory rate	21.00%	21.00%
Change in valuation allowance	(28.52%)	(30.44%)
Return to provision and deferred true-up		0.38%
Change in rate	(0.33%)	0.03%
State tax benefit (net of federal)	3.39%	4.35%
Warrant liability	1.71%	2.02%
State research and development credit	0.09%	0.22%
Federal research and development credit	1.44%	3.30%
Amortization	(0.29%)
Stock-based compensation	(1.10%)	(0.63%)
Other	2.70%	(0.01%)
Federal income tax provision effective rate	0.09%	0.22%

Note N - Income Taxes - Compone

Note N - Income Taxes - Components of Net Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Net operating loss carryforwards	$ 56,827	$ 51,269
Research and development tax carryforward	6,412	5,657
Other deferred tax assets	4,488	3,437
Total gross deferred tax assets	67,726	60,363
Property and equipment		161
Other deferred tax liabilities	540	10
Total gross deferred tax liabilities	540	171
Deferred tax assets less liabilities	67,186	60,192
Valuation allowance	(67,186)	(60,192)
Net deferred tax asset (liability)

Note N - Income Taxes - Federal

Note N - Income Taxes - Federal Net Operating Loss Carryforward and Research Activities Credit (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Net Operating Loss Carryforwards	$ 217,085
Research Activities Tax Credit	6,412	$ 5,657
Tax Year 2007 [Member]
Net Operating Loss Carryforwards	454
Research Activities Tax Credit	$ 30
Expiration	2027
Tax Year 2008 [Member]
Net Operating Loss Carryforwards	$ 1,178
Research Activities Tax Credit	$ 65
Expiration	2028
Tax Year 2009 [Member]
Net Operating Loss Carryforwards	$ 3,060
Research Activities Tax Credit	$ 176
Expiration	2029
Tax Year 2010 [Member]
Net Operating Loss Carryforwards	$ 3,423
Research Activities Tax Credit	$ 149
Expiration	2030
Tax Year 2011 [Member]
Net Operating Loss Carryforwards	$ 9,929
Research Activities Tax Credit	$ 176
Expiration	2031
Tax Year 2012 [Member]
Net Operating Loss Carryforwards
Research Activities Tax Credit	$ 170
Expiration	2032
Tax Year 2013 [Member]
Net Operating Loss Carryforwards	$ 4,353
Research Activities Tax Credit	$ 133
Expiration	2033
Tax Year 2014 [Member]
Net Operating Loss Carryforwards	$ 15,897
Research Activities Tax Credit	$ 894
Expiration	2034
Tax Year 2015 [Member]
Net Operating Loss Carryforwards	$ 23,496
Research Activities Tax Credit	$ 598
Expiration	2035
Tax Year 2016 [Member]
Net Operating Loss Carryforwards	$ 41,580
Research Activities Tax Credit	$ 745
Expiration	2036
Tax Year 2017 [Member]
Net Operating Loss Carryforwards	$ 34,776
Research Activities Tax Credit	$ 652
Expiration	2037
Tax Year 2018 [Member]
Net Operating Loss Carryforwards	$ 56,155
Research Activities Tax Credit	2,272
Tax Year 2019 [Member]
Net Operating Loss Carryforwards	22,784
Research Activities Tax Credit	$ 352

Note O - Net Loss Per Share (De

Note O - Net Loss Per Share (Details Textual) - shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	38,630,026	12,993,641
Optional Exchange Principal Amount [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	26,439,015

Note O - Net Loss Per Share - S

Note O - Net Loss Per Share - Summary of Computation of Basic and Diluted Net Loss and Net Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Net loss - basic and diluted	$ (24,522)	$ (56,466)
Weighted average number of shares of common stock - basic and diluted (in shares)	29,654,968	17,930,023
Net loss per share - basic and diluted (in dollars per share)	$ (0.83)	$ (3.15)

Note O - Net Loss Per Share - A

Note O - Net Loss Per Share - Anti-dilutive Securities (Details) - shares		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018
Antidilutive securities (in shares)		38,630,026	12,993,641
Convertible Debt Securities [Member]
Antidilutive securities (in shares)		1,213,606	1,167,607
2021 Notes [Member]
Antidilutive securities (in shares)		175,336	4,481,182
The 2019 Notes [Member]
Antidilutive securities (in shares)	[1]	29,625,785
Share-based Payment Arrangement [Member]
Antidilutive securities (in shares)		5,192,222	3,704,755
Warrants to Purchase Common Stock [Member]
Antidilutive securities (in shares)		2,423,077	2,527,763
Series A Convertible Preferred Stock [Member]
Antidilutive securities (in shares)			1,112,334
[1]	Inclusive of 26,439,015 of shares of Common Stock issuable (i) in exchange of the Deerfield Optional Conversion Feature, or (ii) upon conversion of the Series B-2 Preferred Stock issuable in exchange of the Deerfield Optional Conversion Feature.

Note P - Severance Expense (Det

Note P - Severance Expense (Details Textual) - USD ($) $ in Thousands	Aug. 31, 2018	Feb. 07, 2021	Dec. 31, 2019	Dec. 31, 2018
Share-based Payment Arrangement, Expense			$ 4,410	$ 6,495
Severance Costs				1,636
Severance Expense [Member]
Share-based Payment Arrangement, Expense				1,236
Employee Severance [Member] | Forecast [Member] | Chief Executive Officer [Member]
Share-based Payment Arrangement, Expense		$ 600
Severance Costs		1,000
Payments for Restructuring		$ 400
Employee Severance [Member] | Accounts Payable and Accrued Liabilities [Member]
Accrued Severance Expense				$ 200
Employee Severance [Member] | Severance Expense [Member]
Severance Charges	$ 400		$ 0
Share-based Payment Arrangement, Expense	$ 1,200

Note Q - Employee Benefit Plan

Note Q - Employee Benefit Plan (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Retirement Plan [Member]
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	4.00%
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 133,000	$ 212,000
Profit Sharing Plan [Member]
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 0	$ 0
Defined Contribution Plan, Requisite Service Period	3 years