Enzon Pharmaceuticals (ENZN) 10-K23 Feb 212020 FY Annual reportFinancial data

Company Profile

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Dec. 31, 2020	Feb. 12, 2021	Jun. 30, 2020
Document and Entity Information
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Entity Registrant Name	ENZON PHARMACEUTICALS, INC.
Entity Central Index Key	0000727510
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Title of 12(g) Security	Common Stock, $0.01 par value
Entity Public Float			$ 6,394,672
Trading Symbol	ENZN
Entity Common Stock, Shares Outstanding		74,214,603
Entity Shell Company	false
Entity Emerging Growth Company	false
Entity Small Business	true
Entity Interactive Data Current	Yes

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 48,142	$ 5,446
Royalty receivable	31
Refundable tax credits receivable, current portion		485
Other current assets	59	62
Total current assets	48,232	5,993
Refundable tax credits receivable, net of current portion		485
Total assets	48,232	6,478
Current liabilities:
Accounts payable	302	324
Accrued expenses and other current liabilities	110	99
Total current liabilities	412	423
Commitments and contingencies
Stockholders' equity:
Preferred stock - $0.01 par value, authorized 2,960,000 shares; no shares issued and outstanding at December 31, 2020 and 2019
Common stock - $0.01 par value, authorized 170,000,000 shares; issued and outstanding 74,214,603 shares at December 31, 2020 and 44,214,603 at December 31, 2019	742	442
Additional paid-in capital	78,006	75,690
Accumulated deficit	(71,388)	(70,077)
Total stockholders' equity	7,360	6,055
Total liabilities, mezzanine equity and stockholders' equity	48,232	$ 6,478
Series C Preferred Stock
Mezzanine equity:
Series C preferred stock - $0.01 par value, 40,000 shares authorized, issued and outstanding (liquidation value $1,012 per share) at December 31, 2020; no shares issued and outstanding at December 31, 2019	40,460
Stockholders' equity:
Total stockholders' equity	$ 40,460

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
MEZZANINE EQUITY
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	2,960,000	2,960,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	170,000,000	170,000,000
Common stock, shares issued	74,214,603	44,214,603
Common stock, shares outstanding	74,214,603	44,214,603
Series C Preferred Stock
MEZZANINE EQUITY
Preferred Shares, par value	$ 0.01	$ 0.01
Preferred Shares, shares authorized	40,000	40,000
Preferred Shares, shares issued	40,000	0
Preferred Shares, shares outstanding	40,000	0
Preferred Shares, liquidation value	$ 1,012
Preferred stock, shares authorized	40,000

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Revenues:
Royalties and milestones, net	$ 52	$ 207
Total revenues	52	207
Operating expenses:
General and administrative	1,357	1,180
Total operating expenses	1,357	1,180
Operating loss	(1,305)	(973)
Other income	1
Loss before income tax expense	(1,304)	(973)
Income tax expense	7	6
Net loss	(1,311)	(979)
Dividends on Series C preferred stock	(460)
Net loss available to common shareholders	$ (1,771)	$ (979)
Loss per common share
Basic and diluted (in dollars per share)	$ (0.03)	$ (0.02)
Weighted average number of common shares
Basic and diluted (in shares)	51,100	44,215

CONSOLIDATED STATEMENTS OF MEZZ

CONSOLIDATED STATEMENTS OF MEZZANINE EQUITY AND STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Series C Preferred StockRights Offering	Series C Preferred Stock	Common StockRights Offering	Common Stock	Additional Paid-in CapitalRights Offering	Additional Paid-in Capital	Accumulated Deficit	Rights Offering	Total
Balance at Dec. 31, 2018				$ 442		$ 83,649	$ (69,098)		$ 14,993
Balance (in shares) at Dec. 31, 2018				44,215,000
Net loss		$ 0		$ 0		0	(979)		(979)
Preferred stock dividend accumulation						(7,959)			(7,959)
Balance at Dec. 31, 2019				$ 442		75,690	(70,077)		6,055
Balance (in shares) at Dec. 31, 2019				44,215,000
Net loss		0		$ 0		0	(1,311)		(1,311)
Preferred stock dividend accumulation		(460)				(460)			(460)
Rights offering, proceeds net of expenses (Note 2)	$ 40,000		$ 300		$ 2,776			$ 3,076
Rights offering, proceeds net of expenses (Note 2) (in shares)	40,000		30,000,000
Balance at Dec. 31, 2020		$ 40,460		$ 742		$ 78,006	$ (71,388)		$ 7,360
Balance (in shares) at Dec. 31, 2020		40,000		74,215,000

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities:
Net loss	$ (1,311)	$ (979)
Changes in operating assets and liabilities:
Decrease in milestone receivable		7,000
(Increase) decrease in other current assets and accounts receivable	(28)	8
Decrease in refundable tax credit receivable	970	970
Decrease in accounts payable	(22)	(115)
Increase in accrued expenses and other current liabilities	11	21
Net cash (used in) provided by operating activities	(380)	6,905
Cash flows from financing activities:
Payment of offering costs	(524)
Proceeds from rights offering	43,600
Common stock dividends	0	(7,959)
Net cash provided by (used in) financing activities	43,076	(7,959)
Net increase (decrease) in cash	42,696	(1,054)
Cash and cash equivalents at beginning of year	5,446	6,500
Cash and cash equivalents at end of year	48,142	5,446
Series C Preferred Stock
Cash flows from operating activities:
Net loss	0	$ 0
Non-cash financing activities:
Accretion of Dividend for Series C Preferred Stock	$ 460

Description of Business

Description of Business	12 Months Ended
Description of Business	Dec. 31, 2020
Description of Business
Description of Business	(1) Description of Business Enzon Pharmaceuticals, Inc. (together with its subsidiaries, the “Company,” “Enzon,” “we” or “us”) is positioned as a public company acquisition vehicle, where it can become an acquisition platform and more fully utilize its net operating loss carryforwards (“NOLs”) and enhance stockholder value. In September 2020, the Company initiated a rights offering for its common and preferred stock (see below and Note 14 to our Condensed Consolidated Financial Statements), which closed in October 2020, and it realized $43.6 million in gross proceeds. This has enabled the Company to embark on its plan to realize the value of its approximately $103 million net operating losses (“NOLs”) by acquiring potentially profitable businesses or assets. To protect the NOLs, in August 2020, the Company’s Board of Directors adopted a Section 382 rights plan (see Note 13 to our Condensed Consolidated Financial Statements). Historically, the Company had received royalty revenues from licensing arrangements with other companies primarily related to sales of certain drug products that utilized Enzon’s proprietary technology. In recent years, the Company has had no clinical operations and limited corporate operations. Enzon has a marketing agreements in the drug Vicineum, which, if approved, will potentially generate milestone and royalty payments to it in the future. Enzon cannot assure you that it will earn material future royalties or milestones. On January 30, 2019, the Company entered into a letter agreement with Servier, a wholly owned indirect subsidiary of Les Laboratoires Servier, in connection with the asset purchase agreement dated as of November 9, 2009 (the “Asset Purchase Agreement”), by and between Klee Pharmaceuticals, Inc., Defiante Farmacêutica, S.A. (“Defiante”) and Sigma-Tau, on the one hand, and the Company, on the other hand. Under the letter agreement, Servier, as successor-in-interest to Defiante, confirmed its obligation to pay the Company a $7.0 million milestone payment related to SC Oncaspar as a result of the U.S. Food and Drug Administration's ("FDA") December 20, 2018 approval of calaspargase pegol – mknl (brand name ASPARLAS™) as a component of a multi-agent chemotherapeutic regimen for the treatment of acute lymphoblastic leukemia in pediatric and young adult patients age one month to 21 years. In addition, under the letter agreement, the Company agreed to waive Servier’s obligations to pursue the development of SC Oncaspar in Europe and the approval of SC Oncaspar by the European Medicines Agency (“EMEA”) under the Asset Purchase Agreement, provided that the Company did not waive Servier’s obligation to make any applicable milestone payment to the Company upon EMEA approval, if any, of SC Oncaspar. Servier was required to make the $7.0 million milestone payment to the Company within three business days following the parties’ completion of procedures for claiming benefits under the double tax treaty between the United States and the United Kingdom. The Company recorded that amount as a current receivable at December 31, 2018. The Company received the $7.0 million payment in July 2019. The Company has a marketing agreement with Micromet AG, now part of Amgen, Inc. (the “Micromet Agreement”), pursuant to which the Company may be entitled to a share of certain milestone and royalty payments if Vicineum, a drug being developed by Sesen Bio, Inc. (“Sesen”) , is approved for the treatment of non-muscle invasive bladder cancer. In a press release dated February 16, 2021, Sesen announced that the U.S. Food and Drug Administration (the “FDA”) has accepted for filing Sesen’s Biologic License Application (“BLA”) for Vicineum. The FDA further granted Priority Review, with a target Prescription Drug User Fee Act (“PDUFA”) date for a decision on the BLA of August 18, 2021. Due to the challenges associated with developing and obtaining approval for drug products, and the lack of involvement by the Company in the development and approval process, there is substantial uncertainty as to whether the Company will receive any milestone or royalty payments under the Micromet Agreement. The Company will not recognize revenue until all revenue recognition requirements are met. In August 2020, the Company’s Board of Directors adopted a Section 382 rights plan and declared a dividend distribution of one right for each outstanding share of the Company’s common stock to stockholders of record at the close of business on August 24, 2020. (See Note 13 to the Consolidated Financial Statements.) In September 2020, the Company’s Board of Directors approved a Rights Offering (the “Rights Offering”), by which the Company distributed, at no charge to all holders of its common stock on September 23, 2020 (the “Record Date”), transferable subscription rights to purchase units (“Units”) at a subscription price per Unit of $1,090. In the Rights Offering, each stockholder on the Record Date received one subscription right for every share of common stock owned on the Record Date. For every 1,105 subscription rights held, a stockholder was entitled to purchase one Unit at the subscription price. Each Unit consisted of one share of newly designated Series C Preferred Stock, par value $0.01 per share, and 750 shares of the Company’s common stock. The subscription period for the Rights Offering ended on October 9, 2020. As a result of the sale of all 40,000 Units available for purchase in the Rights Offering, the Company received approximately $43.6 million of gross proceeds and had 40,000 shares of Series C Preferred Stock outstanding and an aggregate of 74,214,603 shares of common stock outstanding following the Rights Offering. (See Note 14 to the Consolidated Financial Statements.) On December 31st of each year, the Company’s Board of Directors may, at its sole discretion, cause a dividend with respect to the Series C Preferred Stock to be paid in cash to the holders in an amount equal to 3% of the liquidation preference as in effect at such time (initially $1,000 per share). If the dividend is not so paid in cash, the liquidation preference will be adjusted and increased annually by an amount equal to 5% of the liquidation preference per share as in effect at such time, that is not paid in cash to the holders on such date. The Company’s Board of Directors did not declare a dividend as of December 31, 2020 and, at December 31, 2020, the liquidation value of the Series C Preferred Stock was $1,012 per share. (See Note 15 to the Consolidated Financial Statements.) The Company maintains its principal executive offices at 20 Commerce Drive, Suite 135, Cranford, New Jersey 07016 through a service agreement with Regus Management Group, LLC.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
Summary of Significant Accounting Policies	Dec. 31, 2020
Summary of Significant Accounting Policies
Summary of Significant Accounting Policies	(2) Summary of Significant Accounting Policies Principles of Consolidation The consolidated financial statements include the accounts of Enzon Pharmaceuticals, Inc. and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated as part of the consolidation. Use of Estimates The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect reported amounts of assets and liabilities, disclosures of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. These estimates include legal and contractual contingencies and income taxes. Although management bases its estimates on historical experience, relevant current information and various other assumptions that are believed to be reasonable under the circumstances, actual results could differ from these estimates. Deferred Stock Offering Expenses The Company classified expenses related to the Rights Offering (See Note 14 to the Consolidated Financial Statements) not completed as of the balance sheet date as Deferred Stock Offering Expenses. Such expenses, aggregating approximately $524,000, were reclassified as an offset to Additional Paid-in-Capital upon completion of the Rights Offering. Financial Instruments and Fair Value The carrying values of cash and cash equivalents, royalty receivable, other current assets, accounts payable, accrued expenses and other current liabilities in the Company’s consolidated balance sheets approximated their fair values at December 31, 2020 and 2019 due to their short-term nature. As of December 31, 2020, the Company held cash equivalents aggregating approximately $43.6 million. Revenue Recognition Royalty revenues from the Company’s agreements with third parties are recognized when the Company can reasonably determine the amounts earned. In most cases, this will be upon notification from the third-party licensee, which is typically during the quarter following the quarter in which the sales occurred. The Company does not participate in the selling or marketing of products for which it receives royalties. As a result, no provision for uncollectible accounts is established upon recognition of revenues. Contingent payments due under the Asset Purchase Agreement for the sale of the Company’s former specialty pharmaceutical business are recognized as income when the milestone has been achieved and collection is assured, such payments are non-refundable and no further effort is required on the part of the Company or the other party to complete the earning process. Income Taxes Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be realized. The effect of a change in tax rates or laws on deferred tax assets and liabilities is recognized in operations in the period that includes the enactment date of the rate change. A valuation allowance is established to reduce the deferred tax assets to the amounts that are more likely than not to be realized from operations. Tax benefits of uncertain tax positions are recognized only if it is more likely than not that the Company will be able to sustain a position taken on an income tax return. The Company has no liability for uncertain tax positions. Interest and penalties, if any, related to unrecognized tax benefits would be recognized as income tax expense.

Recent Accounting Pronouncement

Recent Accounting Pronouncements	12 Months Ended
Recent Accounting Pronouncements	Dec. 31, 2020
Recent Accounting Pronouncements
Recent Accounting Pronouncements	(3) Recent Accounting Pronouncements The Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) No. 2016-02, Leases (Topic 842) and several related ASUs on practical expedient and targeted improvements. These ASUs require lessees to recognize the assets and liabilities that arise from leases on the balance sheets. A lessee should recognize in the statement of financial position a liability to make lease payments (the lease liability) and a right-of-use asset representing its right to use the underlying asset for the lease term. The Company adopted these ASUs on accounting for leases effective January 1, 2019. Due to the current nature of the Company’s lease obligations, adoption of the standard did not have a material effect on the Company’s consolidated financial statements. The Company adopted, ASU 2016-13, "Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments”, effective January 1, 2020. The amendments of ASU 2016-13 are intended to provide information related to expected credit losses on financial instruments and other commitments to extend credit. Due to the current nature of the Company’s financial instruments and other commitments, adoption of the standard did not have a material effect on the Company’s consolidated financial statements .

Accounts Payable and Accrued Ex

Accounts Payable and Accrued Expenses	12 Months Ended
Accounts Payable and Accrued Expenses	Dec. 31, 2020
Accounts Payable and Accrued Expenses
Accounts Payable and Accrued Expenses	(4) Accounts Payable and Accrued Expenses As of December 31, 2018, according to Merck, the Company had a net liability to Merck (net of a 25% royalty interest held by DRI Capital, Inc.) aggregating approximately $439,000. This was based on Merck’s assertions regarding the net result of overpayments, rebates and returns related to prior periods’ sales of PegIntron. Merck expected to recoup such overpayments through reductions of future royalties earned by the Company. In the year ended December 31, 2019, net royalties from PegIntron were approximately $115,000. As such, as asserted by Merck, the Company’s net liability to Merck was $324,000 at December 31, 2019. During the year ended December 31, 2020, net royalty revenues from Merck aggregated approximately $22,000. Accordingly, as asserted by Merck, the Company’s net liability to Merck was approximately $302,000 at December 31, 2020. The Company believes that it will receive little or no future royalties from Merck, but may be charged with additional chargebacks from returns and rebates in amounts that, based on current estimates, are not expected to be material. Accrued expenses and other current liabilities consisted of the following as of December 31, 2020 and 2019 (in thousands): December 31, December 31, 2020 2019 Professional and consulting fees $ 92 $ 81 Other 18 18 $ 110 $ 99

Stockholders' Equity

Stockholders' Equity	12 Months Ended
Stockholders' Equity	Dec. 31, 2020
Stockholders' Equity
Stockholders' Equity	(5) Stockholders’ Equity Preferred Stock The Company has authorized 3,000,000 shares of preferred stock in one or more series of which, at December 31, 2020, 40,000 shares have been issued, are outstanding and are designated as Series C in connection with the Rights Offering discussed in Note 14 and 100,000 shares have been designated as Series A-1 Junior Participating Preferred Stock in connection with the August 2020 Section 382 rights plan discussed in Note 13. Common Stock As of December 31, 2020, the Company reserved 9,818,392 shares of its common stock for the non-qualified and incentive stock plans.

Cash Dividend

Cash Dividend	12 Months Ended
Cash Dividend	Dec. 31, 2020
Cash Dividend
Cash Dividend	(6) Cash Dividend On January 30, 2019, the Board declared a special cash dividend of $0.06 per share of the Company’s common stock, aggregating approximately $2,653,000, which was paid on March 21, 2019 to stockholders of record as of the close of business on February 21, 2019. On August 22, 2019, the Board declared a special cash dividend of $0.12 per share of the Company’s common stock, aggregating approximately $5,306,000, which was paid on October 15, 2019 to stockholders of record at the close of business on October 1, 2019.

Loss Per Common Share

Loss Per Common Share	12 Months Ended
Loss Per Common Share	Dec. 31, 2020
Loss Per Common Share
Loss Per Common Share	(7) Loss Per Common Share Basic earnings (loss) per common share (EPS) is calculated by dividing net income (loss), less any dividends, accretion or reduction of redemption on our Series C Preferred Stock, by the weighted average number of common shares outstanding during the reported period. Restricted stock awards and restricted stock units (collectively, “nonvested shares”) are not considered to be outstanding shares until the service or performance vesting period has been completed. The diluted earnings per common share calculation would normally involve adjusting both the denominator and numerator as described here if the effect is dilutive. For purposes of calculating diluted earnings per common share, the denominator normally includes both the weighted-average number of shares of common stock outstanding and the number of common stock equivalents if the inclusion of such common stock equivalents is dilutive. Because a loss was incurred in each of the years ended December 31, 2020 and 2019, common stock equivalents would be anti-dilutive and, accordingly, were excluded from the calculation of diluted loss per share in each of the periods. Dilutive common stock equivalents potentially include stock options and nonvested shares using the treasury stock method and shares issuable under the employee stock purchase plan. During each of the years ended December 31, 2020 and 2019, there were no common stock equivalents. Loss per common share information was as follows (in thousands, except per share amounts) for the years ended December 31, 2020 and 2019: 2020 2019 Loss per Common Share – Basic and Diluted Net loss for year $ (1,311) $ (979) Dividends on Series C preferred stock (460) — Net loss available to common shareholders $ (1,771) $ (979) Weighted-average number of common shares outstanding 51,100 44,215 Basic and diluted loss per common share $ (0.03) $ (0.02) At December 31, 2020 and 2019, options for 25,000 and 41,787 shares, respectively, were outstanding that have been excluded from the calculation of diluted weighted-average number of shares outstanding, as they would be anti-dilutive, since the respective options’ strike price was greater than the market price of the respective shares.

Stock Options

Stock Options	12 Months Ended
Stock Options	Dec. 31, 2020
Stock Options
Stock Options	(8) Stock Options Through the Compensation Committee of the Board, the Company administers the 2011 Stock Option and Incentive Plan (the "2011 Plan"), which provides incentive and non-qualified stock option benefits for employees, officers, directors and independent contractors providing services to Enzon. Options granted to employees generally vest over four years from date of grant and options granted to directors vest after one year. The exercise price of the options granted must be at least 100 percent of the fair value of the Company’s common stock at the time the options are granted. Options may be exercised for a period of up to ten years from the grant date. As of December 31, 2020, the 2011 Plan authorized equity-based awards for 5.0 million common shares of which approximately 4.6 million shares remained available for grant. However, there will be no further grants made pursuant to this plan. In connection with the special cash dividends that were paid on March 21, 2019 to stockholders of record as of February 21, 2019 and on October 15, 2019 to stockholders of record as of October 1, 2019 (See Note 6 to the Consolidated Financial Statements), the Compensation Committee of the Board approved equitable adjustments to the Company’s outstanding stock options and restricted stock units. The following summary of the activity in the Company’s outstanding stock option plans, includes the 2011 Stock Option and Incentive Plan, the 2001 Incentive Stock Plan, and the 1987 Non-Qualified Stock Option Plan and reflects the equitable adjustments approved by the Board (options in thousands): Weighted Weighted Average Average Exercise Remaining Aggregate Price Per Contractual Intrinsic Options Option Term (years) Value ($000) Outstanding at December 31, 2020 and 2019 December 31, 2019 42 $ 2.93 $ — Expired and forfeited (17) — — — December 31, 2020 25 $ 1.31 $ — Vested at December 31, 2020 and 2019 December 31, 2019 42 $ 2.93 1.23 $ — Expired and forfeited (17) December 31, 2020 25 $ 1.31 $ — Exercisable at December 31, 2020 and 2019 December 31, 2019 42 $ 2.93 1.23 $ — Expired and forfeited (17) December 31, 2020 25 $ 1.31 $ — As of December 31, 2020, there was no unrecognized compensation cost related to unvested options that the Company expects to recognize. No options were granted during the years ended December 31, 2020 and 2019. During the years ended December 31, 2020 and 2019, the Company recorded no stock-based compensation related to stock options. The Company’s policy is to use newly issued shares to satisfy the exercise of stock options. The Company received no cash from exercises of stock options during either of the years ended December 31, 2020 and 2019.

Income Taxes

Income Taxes	12 Months Ended
Income Taxes	Dec. 31, 2020
Income Taxes
Income Taxes	(9) Income Taxes The components of the income tax provision are summarized as follows (in thousands): Year Ended December 31, 2020 2019 Current: Federal $ — $ — State and foreign 7 6 Total current 7 6 Deferred: Federal and state — — Income tax provision $ 7 $ 6 The following table represents the reconciliation between the reported income taxes and the income taxes that would be computed by applying the federal statutory rate (21% for years ended December 31, 2020 and 2019) to income before taxes (in thousands): Year Ended December 31, 2020 2019 Income tax provision at federal statutory rate $ (274) $ (204) Add (deduct) effect of: State income taxes, net of federal tax (86) (65) Expiration of federal research and development credits 1,039 416 Expiration of capital loss carryforwards — — Change in valuation allowance (672) (141) Income tax provision $ 7 $ 6 No federal income tax expense was incurred in relation to normal operating. As of December 31, 2020 and 2019, the cumulative tax effects of temporary differences that give rise to the deferred tax assets were as follows (in thousands): December 31, December 31, 2020 2019 Deferred tax assets: Federal and state net operating loss carryforward $ 23,398 $ 23,030 Research and development credits carryforward 14,795 15,835 Total gross deferred tax assets 38,193 38,865 Less valuation allowance (38,193) (38,865) Net deferred tax assets $ — $ — ASC 740 requires the reduction of deferred tax assets by a valuation allowance if, based on the weight of available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. For the period ended December 31, 2019, the Company believed that it was more likely than not that future taxable income would not exist to utilize some or all of its deferred tax assets. Accordingly, it recorded a valuation allowance in the amount of its total deferred tax assets for the period ended December 31, 2019. In 2020, the Company generated approximately $1.3 million in taxable loss before utilization of NOLs. The Company utilized none of the NOLs due to the taxable loss position. Due to the valuation allowance placed on its deferred tax assets, the deferred tax expense resulting from the usage and/or expiration of deferred tax assets was offset by a corresponding deferred tax benefit from a reduction in valuation allowance, and the Company recorded no deferred tax expense at December 31, 2020. The Company intends to acquire profitable businesses, entities or revenue streams that will generate sufficient income so that it can utilize its approximately $103 million NOLs. To date, no actionable acquisition candidates have been identified and, while the Company expects that, ultimately, it will be successful in realizing the value of its NOLs, the Company cannot provide assurance that it will be able to do so. Management of the Company will continue to assess the need for this valuation allowance and will make adjustments when appropriate. At December 31, 2020, the Company had federal NOLs of approximately $103 million, of which approximately $100.6 million will expire in the years 2025 through 2036, and New Jersey state NOLs of approximately $25.2 million that expire in the years 2031 through 2040. Under the Tax Cuts and Jobs Act, net operating losses generated in tax years beginning after December 31, 2017 have an unlimited carryforward period, and the amount of net operating loss allowed to be utilized each year is limited to 80% of taxable income. The Coronavirus Aid, Relief and Economic Security Act (the “CARES Act”) was signed into law on March 27, 2020 and provides for a five-year carryback period for net operating losses generated after 2017, but before 2021. The CARES Act also removes the annual utilization limit of 80% of taxable income and allows the net operating losses to offset 100% of taxable income during this period. Net operating losses generated in 2018 and later have an indefinite carryforward period and net operating losses generated prior to 2018 continue to be carried forward for 20 years and have no 80% limitation on utilization. The Company had federal and state capital loss carryforwards of approximately $1.2 million that expired in 2018. The Company also had federal research and development (“R&D”) credit carryforwards of approximately $1.0 million that expired in 2020. The Company has remaining R&D credit carryforwards of approximately $14.8 million that expire in the years 2021 through 2029. These deferred tax assets were subject to a valuation allowance such that the deferred tax expense incurred as a result of the expiration of the capital loss and R&D credit carryforwards was offset by a corresponding deferred tax benefit for the related reduction in valuation allowance. The Company’s ability to use the NOLs and R&D tax credit carryforwards may be limited, as they are subject to certain limitations due to ownership changes as defined by rules pursuant to Section 382 of the Internal Revenue Code of 1986, as amended. However, management of the Company believes that the Company’s NOLs will not be limited by any changes in the Company’s ownership as a result of the successful completion of the Rights Offering. (See Note 14 to the Consolidated Financial Statements.) Additionally, in an effort to protect stockholder value by attempting to protect against a possible limitation on the Company’s ability to use its NOLs, the Board adopted a Section 382 rights plan. (See Note 13 to the Consolidated Financial Statements.) On December 22, 2017, the Tax Cuts and Jobs Act was signed into law. Among its numerous changes to the Internal Revenue Code, the Tax Cut and Jobs Act allowed companies with existing alternative minimum tax credit (“MTC”) carryforwards as of December 31, 2017 to receive refunds of the credits in tax years after 2017 and before 2022 in an amount equal to 50% (100% in 2021) of the excess MTC over the amount of the credit allowable for the year against regular tax liability. As a result of the Tax Cuts and Jobs Act’s provision allowing for the refund of MTC, the Company recorded $485,000 as a long-term receivable and $485,000 as a current receivable as of December 31, 2019. As a result of provisions in the CARES Act both the current and long-term amounts were received in 2020. The Company has not recorded a liability for unrecognized income tax benefits.

Significant Agreements

Significant Agreements	12 Months Ended
Significant Agreements	Dec. 31, 2020
Significant Agreements
Significant Agreements	(10) Significant Agreements Merck Agreement See Note 4 to the Consolidated Financial Statements regarding Merck royalty revenues. Servier Agreement See Note 1 to the Consolidated Financial Statements regarding the Servier milestone obligation to the Company.

Commitments and Contingent Liab

Commitments and Contingent Liabilities	12 Months Ended
Commitments and Contingent Liabilities	Dec. 31, 2020
Commitments and Contingent Liabilities
Commitments and Contingent Liabilities	(11) Commitments and Contingent Liabilities In December 2019, an outbreak of a novel strain of coronavirus (COVID-19) was reported in Wuhan, China. On March 11, 2020, the World Health Organization characterized the global spread of COVID-19 as a pandemic. In an effort to slow the spread of the virus, the United States and many other countries around the world imposed restrictions on non-essential work activities, travel and mass gatherings. Although these restrictions have been eased in some areas, it is not known whether these lockdowns and other restrictions will be reintroduced, especially in light of the uncertainty regarding cases in the United States, when they will end or the ultimate impact these unprecedented actions will have on the Company’s financial condition and prospects. At the present time, the Company’s business activities have been largely unaffected by COVID-19 restrictions as the Company’s workforce is comprised solely of independent contractors who are able to perform their duties remotely. However, these restrictions may impact the third parties who are responsible for obtaining final approval of and manufacturing product candidates for which the Company shares the right to receive licensing fees, milestone payments and royalty revenues. If those third parties are required to curtail their business activities for a significant time, or if global supply chain disruptions impact their ability to procure needed resources, raw materials or components, the Company’s right to receive licensing fees, milestone payments or royalties could be materially and adversely affected. Additionally, the development timeline for product candidates being developed by third parties that are pending FDA or other regulatory approval could be delayed if the agency is required to shift resources to the review and approval of candidates for treatment of COVID-19. In addition, the effects of the COVID-19 pandemic, including the current global challenges, may negatively impact the Company’s search for a business acquisition or investment, as well as negatively impacting the business and/or results of operations of any target business which the Company acquires or in which it invests. The Company has been involved in various claims and legal actions arising in the ordinary course of business. In the opinion of management, the ultimate disposition of these matters will not have a material effect on the Company’s consolidated financial position, results of operations, or liquidity.

Other Corporate Events

Other Corporate Events	12 Months Ended
Other Corporate Events	Dec. 31, 2020
Other Corporate Events
Other Corporate Events	(12) Other Corporate Event Former Plan of Liquidation and Dissolution On February 4, 2016, the Company’s Board of Directors adopted a Plan of Liquidation and Dissolution, pursuant to which the Company would, subject to obtaining requisite stockholder approval, be liquidated and dissolved. On November 9, 2020, the Company’s Board of Directors withdrew and terminated the Plan of Liquidation and Dissolution as a result of the completion of the Rights Offering. (See Note 14 to the Consolidated Financial Statements.)

Section 382 Rights Plan

Section 382 Rights Plan	12 Months Ended
Section 382 Rights Plan	Dec. 31, 2020
Section 382 Rights Plan
Section 382 Rights Plan	(13) Section 382 Rights Plan On August 14, 2020, in an effort to protect stockholder value by attempting to protect against a possible limitation on the Company’s ability to use its NOLs, the Company’s Board of Directors adopted a Section 382 rights plan and declared a dividend distribution of one right for each outstanding share of the Company’s common stock to stockholders of record at the close of business on August 24, 2020. Accordingly, holders of the Company’s common stock own one preferred stock purchase right for each share of common stock owned by such holder. The rights are not immediately exercisable and will become exercisable only upon the occurrence of certain events as set forth in the Section 382 rights plan. If the rights become exercisable, each right would initially represent the right to purchase from the Company one one-thousandth of a share of the Company’s Series A-1 Junior Participating Preferred Stock, par value $0.01 per share, for a purchase price of $1.20 per right. If issued, each fractional share of Series A-1 Junior Participating Preferred Stock would give the stockholder approximately the same dividend, voting and liquidation rights as does one share of the Company’s common stock. However, prior to exercise, a right does not give its holder any rights as a stockholder of the Company, including any dividend, voting or liquidation rights. The rights will expire on the earliest of (i) the close of business on August 13, 2021 (unless that date is advanced or extended by the Board), (ii) the time at which the rights are redeemed or exchanged under the Section 382 rights plan, (iii) the close of business on the day of repeal of Section 382 of the Internal Revenue Code or any successor statute or (iv) the close of business on the first day of a taxable year of the Company to which the Company’s Board of Directors determines that no NOLs may be carried forward.

Rights Offering

Rights Offering	12 Months Ended
Rights Offering	Dec. 31, 2020
Rights Offering
Rights Offering	(14) Rights Offering On September 1, 2020, the Company’s Board of Directors approved a Rights Offering. For every 1,105 subscription rights held, a stockholder was entitled to purchase one Unit at the subscription price of $1,090. Each Unit consisted of one share of newly designated Series C Preferred Stock, par value $0.01 per share, and 750 shares of the Company’s common stock. On October 9, 2020, the Rights Offering expired and, as a result of the sale of all 40,000 Units, the Company received approximately $43.6 million in gross proceeds and issued shares of Series C Preferred Stock and shares of common stock such that, following the closing of the Rights Offering, there was an aggregate of 40,000 shares of Series C Preferred Stock outstanding and 74,214,603 shares of common stock outstanding. On December 31st each year, the Company’s Board of Directors may, at its sole discretion, cause a dividend with respect to the Series C Preferred Stock to be paid in cash to the holders in an amount equal to 3% of the liquidation preference as in effect at such time (initially $1,000 per share). If the dividend is not so paid in cash, the liquidation preference will be adjusted and increased annually by an amount equal to 5% of the liquidation preference per share as in effect at such time, that is not paid in cash to the holders on such date. Holders of Series C Preferred Stock do not have any voting rights and the Series C Preferred Stock is not convertible into shares of the Company’s common stock. The initial liquidation value of the Series C Preferred Stock was $1,000 per share. At December 31, 2020, the liquidation value of the Series C Preferred Stock was $1,012 per share. On or after November 1, 2022, the Company may redeem the Series C Preferred Stock at any time, in whole or in part, for an amount based on the liquidation preference per share as in effect at such time. Holders of Series C Preferred Stock have the right to demand that the Company redeem their shares in the event that the Company undergoes a change of control as defined in the Certificate of Designation of the Series C Preferred Stock.

Series C Preferred Stock

Series C Preferred Stock	12 Months Ended
Series C Preferred Stock	Dec. 31, 2020
Series C Preferred Stock
Series C Preferred Stock	(15) Series C Preferred Stock In October 2020, the Company issued 40,000 shares of Series C Preferred Stock for an aggregate purchase price of $40.0 million. As of December 31, 2020, the Company’s Board of Directors had not declared a cash dividend on the Series C Preferred Stock. Accordingly, the Company recorded a 5% increase (computed on a pro rata basis) to the liquidation preference of approximately $12 per share of Series C Preferred Stock, aggregating approximately $460,000, for a cumulative liquidation value approximately $40,460,000 of as of December 31, 2020. After November 1, 2022, there is no prohibition on the repurchase or redemption of Series C Preferred Shares while there is any arrearage in the payment of dividends. Since the redemption of the Series C Preferred Stock is contingently or optionally redeemable, the Series C Preferred Stock has been classified in mezzanine equity on the Consolidated Balance Sheets.

Subsequent Events

Subsequent Events	12 Months Ended
Subsequent Events	Dec. 31, 2020
Subsequent Events
Subsequent Events	(16) Subsequent Events On January 4, 2021, the Company announced that Andrew Rackear had, on December 30, 2020, communicated to the Board his intent to retire from his role as the Company’s Chief Executive Officer (“CEO”) effective February 26, 2021. On January 4, 2021, the Company also announced that Richard L. Feinstein, Enzon’s Chief Financial Officer (“CFO”), was appointed as CEO and Secretary, effective February 26, 2021, and would remain as the Company’s CFO..

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
Summary of Significant Accounting Policies (Policies)	Dec. 31, 2020
Summary of Significant Accounting Policies
Principles of Consolidation	Principles of Consolidation The consolidated financial statements include the accounts of Enzon Pharmaceuticals, Inc. and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated as part of the consolidation.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect reported amounts of assets and liabilities, disclosures of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. These estimates include legal and contractual contingencies and income taxes. Although management bases its estimates on historical experience, relevant current information and various other assumptions that are believed to be reasonable under the circumstances, actual results could differ from these estimates.
Deferred Stock Offering Expenses	Deferred Stock Offering Expenses The Company classified expenses related to the Rights Offering (See Note 14 to the Consolidated Financial Statements) not completed as of the balance sheet date as Deferred Stock Offering Expenses. Such expenses, aggregating approximately $524,000, were reclassified as an offset to Additional Paid-in-Capital upon completion of the Rights Offering.
Financial Instruments and Fair Value	Financial Instruments and Fair Value The carrying values of cash and cash equivalents, royalty receivable, other current assets, accounts payable, accrued expenses and other current liabilities in the Company’s consolidated balance sheets approximated their fair values at December 31, 2020 and 2019 due to their short-term nature. As of December 31, 2020, the Company held cash equivalents aggregating approximately $43.6 million.
Revenue Recognition	Revenue Recognition Royalty revenues from the Company’s agreements with third parties are recognized when the Company can reasonably determine the amounts earned. In most cases, this will be upon notification from the third-party licensee, which is typically during the quarter following the quarter in which the sales occurred. The Company does not participate in the selling or marketing of products for which it receives royalties. As a result, no provision for uncollectible accounts is established upon recognition of revenues. Contingent payments due under the Asset Purchase Agreement for the sale of the Company’s former specialty pharmaceutical business are recognized as income when the milestone has been achieved and collection is assured, such payments are non-refundable and no further effort is required on the part of the Company or the other party to complete the earning process.
Income Taxes	Income Taxes Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be realized. The effect of a change in tax rates or laws on deferred tax assets and liabilities is recognized in operations in the period that includes the enactment date of the rate change. A valuation allowance is established to reduce the deferred tax assets to the amounts that are more likely than not to be realized from operations. Tax benefits of uncertain tax positions are recognized only if it is more likely than not that the Company will be able to sustain a position taken on an income tax return. The Company has no liability for uncertain tax positions. Interest and penalties, if any, related to unrecognized tax benefits would be recognized as income tax expense.

Accounts Payable and Accrued _2

Accounts Payable and Accrued Expenses (Tables)	12 Months Ended
Accounts Payable and Accrued Expenses (Tables)	Dec. 31, 2020
Accounts Payable and Accrued Expenses
Schedule of accrued liabilities	December 31, December 31, 2020 2019 Professional and consulting fees $ 92 $ 81 Other 18 18 $ 110 $ 99

Loss Per Common Share (Tables)

Loss Per Common Share (Tables)	12 Months Ended
Loss Per Common Share (Tables)	Dec. 31, 2020
Loss Per Common Share
Schedule of loss per common share information, basic and diluted	2020 2019 Loss per Common Share – Basic and Diluted Net loss for year $ (1,311) $ (979) Dividends on Series C preferred stock (460) — Net loss available to common shareholders $ (1,771) $ (979) Weighted-average number of common shares outstanding 51,100 44,215 Basic and diluted loss per common share $ (0.03) $ (0.02)

Stock Options (Tables)

Stock Options (Tables)	12 Months Ended
Stock Options (Tables)	Dec. 31, 2020
Stock Options
Schedule of share-based compensation stock options activity	Weighted Weighted Average Average Exercise Remaining Aggregate Price Per Contractual Intrinsic Options Option Term (years) Value ($000) Outstanding at December 31, 2020 and 2019 December 31, 2019 42 $ 2.93 $ — Expired and forfeited (17) — — — December 31, 2020 25 $ 1.31 $ — Vested at December 31, 2020 and 2019 December 31, 2019 42 $ 2.93 1.23 $ — Expired and forfeited (17) December 31, 2020 25 $ 1.31 $ — Exercisable at December 31, 2020 and 2019 December 31, 2019 42 $ 2.93 1.23 $ — Expired and forfeited (17) December 31, 2020 25 $ 1.31 $ —

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
Income Taxes (Tables)	Dec. 31, 2020
Income Taxes
Schedule of Components of Income Tax Expense (Benefit)	Year Ended December 31, 2020 2019 Current: Federal $ — $ — State and foreign 7 6 Total current 7 6 Deferred: Federal and state — — Income tax provision $ 7 $ 6
Schedule of Effective Income Tax Rate Reconciliation	Year Ended December 31, 2020 2019 Income tax provision at federal statutory rate $ (274) $ (204) Add (deduct) effect of: State income taxes, net of federal tax (86) (65) Expiration of federal research and development credits 1,039 416 Expiration of capital loss carryforwards — — Change in valuation allowance (672) (141) Income tax provision $ 7 $ 6
Schedule of Deferred Tax Assets and Liabilities	December 31, December 31, 2020 2019 Deferred tax assets: Federal and state net operating loss carryforward $ 23,398 $ 23,030 Research and development credits carryforward 14,795 15,835 Total gross deferred tax assets 38,193 38,865 Less valuation allowance (38,193) (38,865) Net deferred tax assets $ — $ —

Description of Business (Detail

Description of Business (Details)	Sep. 23, 2020USD ($)item$ / sharesshares	Oct. 31, 2020USD ($)shares	Jul. 31, 2019USD ($)	Dec. 31, 2020USD ($)$ / sharesshares	Dec. 31, 2019USD ($)$ / sharesshares	Jan. 30, 2019USD ($)	Dec. 31, 2018shares
Description of Business [Line Items]
Proceeds from Royalties Received					$ 115,000
Accounts Payable, Current				$ 302,000	$ 324,000
Common Stock, Par or Stated Value Per Share \| $ / shares				$ 0.01	$ 0.01
Common Stock, Shares Authorized \| shares				170,000,000	170,000,000
Revenues				$ 52,000	$ 207,000
Accrued Royalties, Current					$ 324,000
Royalty receivable				$ 31,000
Proceeds from Milestone on Royalty			$ 7,000,000
Common Stock
Description of Business [Line Items]
Shares, Outstanding \| shares				74,215,000	44,215,000		44,215,000
Rights Offering
Description of Business [Line Items]
Rights offering, proceeds net of expenses (Note 2)				$ 3,076,000
Rights Offering \| Common Stock
Description of Business [Line Items]
Rights offering, proceeds net of expenses (Note 2) (in shares) \| shares				30,000,000
Rights offering, proceeds net of expenses (Note 2)				$ 300,000
Series C Preferred Stock
Description of Business [Line Items]
Shares, Outstanding \| shares				40,000
Preferred Stock, Dividend Preference or Restrictions				the holders in an amount equal to 3% of the liquidation preference as in effect at such time (initially $1,000 per share). If the dividend is not so paid in cash, the liquidation preference will be adjusted and increased annually by an amount equal to 5% of the liquidation preference per share as in effect at such time, that is not paid in cash to the holders on such date.
Temporary Equity, Aggregate Amount of Redemption Requirement				$ 1,012,000
Rights offering, proceeds net of expenses (Note 2) (in shares) \| shares		40,000
Rights offering, proceeds net of expenses (Note 2)		$ 40,000,000
Series C Preferred Stock \| Rights Offering
Description of Business [Line Items]
Rights offering, proceeds net of expenses (Note 2) (in shares) \| shares				40,000
Rights offering, proceeds net of expenses (Note 2)				$ 40,000,000
Board of Directors Chairman \| Rights Offering
Description of Business [Line Items]
Subscription Rights To Purchase Unit	$ 1,090
Number Of Subscription Rights To Purchase Unit \| shares	1,105
Board of Directors Chairman \| Series C Preferred Stock \| Rights Offering
Description of Business [Line Items]
Subscription Per Unit \| item	1
Common Stock, Par or Stated Value Per Share \| $ / shares	$ 0.01
Common Stock, Shares Authorized \| shares	750
Merck [Member]
Description of Business [Line Items]
Accrued Royalties, Current				$ 302,000
Servier IPUK Limited [Member]
Description of Business [Line Items]
Royalty Revenue Milestones		43,600,000
Royalty receivable		$ 103,000,000
Contract with Customer, Liability						$ 7,000,000
Period for milestone payment				3 days
Royalty [Member]
Description of Business [Line Items]
Revenues				$ 22,000
Royalty receivable				$ 7,000,000
Minimum [Member] \| Servier IPUK Limited [Member]
Description of Business [Line Items]
Patient Age				1 month
Maximum [Member] \| Servier IPUK Limited [Member]
Description of Business [Line Items]
Patient Age				21 years

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Details)	12 Months Ended
Summary of Significant Accounting Policies (Details)	Dec. 31, 2020USD ($)
Summary of Significant Accounting Policies
Cash Equivalents, at Carrying Value	$ 43,600,000
Offering Costs	524,000
Provision for Doubtful Accounts	$ 0

Accounts Payable and Accrued _3

Accounts Payable and Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Accounts Payable and Accrued Expenses
Professional and consulting fees	$ 92	$ 81
Other	18	18
Accrued Liabilities, Current, Total	$ 110	$ 99

Accounts Payable and Accrued _4

Accounts Payable and Accrued Expenses - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accounts Payable, Accrued Expenses and Other [Line Items]
Royalty Interest Rate			25.00%
Proceeds from Royalties Received		$ 115,000
Accrued Royalties, Current		324,000
Revenues	$ 52,000	$ 207,000
Royalty [Member]
Accounts Payable, Accrued Expenses and Other [Line Items]
Revenues	22,000
Merck [Member]
Accounts Payable, Accrued Expenses and Other [Line Items]
Due to Related Parties			$ 439,000
Accrued Royalties, Current	$ 302,000

Stockholders' Equity (Details)

Stockholders' Equity (Details) - shares	Dec. 31, 2020	Dec. 31, 2019
Class of Stock [Line Items]
Preferred Stock, Shares Authorized	2,960,000	2,960,000
Non Qualified And Incentive Stock Plans [Member]
Class of Stock [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance	9,818,392
Series A Preferred Stock
Class of Stock [Line Items]
Preferred Stock, Shares Authorized	100,000
Series C Preferred Stock
Class of Stock [Line Items]
Preferred Stock, Shares Authorized	40,000

Cash Dividend (Details)

Cash Dividend (Details) - USD ($) $ / shares in Units, $ in Thousands	Oct. 15, 2019	Aug. 22, 2019	Mar. 21, 2019	Jan. 30, 2019	Dec. 31, 2020	Dec. 31, 2019
Cash Dividend
Common Stock, Dividends, Per Share, Declared		$ 0.12		$ 0.06
Payments of Ordinary Dividends, Common Stock	$ 5,306		$ 2,653		$ 0	$ 7,959

Loss Per Common Share (Details)

Loss Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Loss per Common Share - Basic and Diluted
Net loss for year	$ (1,311)	$ (979)
Dividends on Series C preferred stock	(460)
Net loss available to common shareholders	$ (1,771)	$ (979)
Weighted-average number of common shares outstanding	51,100	44,215
Basic and diluted loss per common share	$ (0.03)	$ (0.02)

Loss Per Common Share - Additio

Loss Per Common Share - Additional Information (Details) - shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Employee Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	25,000	41,787

Stock Options - Activity (Detai

Stock Options - Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Stock Options
Outstanding at December 31, 2019	42
Expired and forfeited	(17)
Outstanding at December 31, 2020	25	42
Outstanding at December 31, 2019	42
Expired and forfeited	(17)
Outstanding at December 31, 2020	25	42
Exercisable at December 31, 2019	42
Expired and forfeited		(17)
Exercisable at December 31, 2020	25	42
Weighted Average Exercise Price per Option, Outstanding at December 31, 2020 and 2019	$ 1.31	$ 2.93
Weighted Average Exercise Price per Option, Vested at December 31, 2020 and 2019	1.31	2.93
Weighted Average Exercise Price per Option, Exercisable at December 31, 2020 and 2019	$ 1.31	$ 2.93
Weighted Average Remaining Contractual Term (years), Outstanding at December 31, 2020 and 2019	1 year 18 days	1 year 2 months 23 days
Weighted Average Remaining Contractual Term (years), Vested at December 31, 2020 and 2019	1 year 18 days	1 year 2 months 23 days
Weighted Average Remaining Contractual Term (years), Exercisable at December 31, 2020 and 2019	1 year 18 days	1 year 2 months 23 days
Aggregate Intrinsic Value, Outstanding at December 31, 2020 and 2019	$ 0	$ 0
Aggregate Intrinsic Value, Vested at December 31, 2020 and 2019	0	0
Aggregate Intrinsic Value, Exercisable at December 31, 2020 and 2019	$ 0	$ 0

Stock Options - Additional Info

Stock Options - Additional Information (Details) - USD ($)	12 Months Ended
Stock Options - Additional Information (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Exercise price as percentage of fair value	100.00%
Expiration period	10 years
Unrecognized compensation cost	$ 0
Options granted during the period	0	0
Stock-based compensation expense	$ 0	$ 0
Proceeds from Stock Options Exercised	$ 0	$ 0
Two Thousand Eleven Stock Incentive Plan [Member]
Number of shares authorized	5,000,000
Number of shares available for grant	4,600,000
Share-based Payment Arrangement, Employee [Member]
Vesting period	4 years
Share-based Payment Arrangement, Nonemployee [Member]
Vesting period	1 year

Income Taxes - Provision compon

Income Taxes - Provision components (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Current:
Federal	$ 0	$ 0
State and foreign	7	6
Total current	7	6
Deferred:
Federal and state	0	0
Income tax provision	$ 7	$ 6

Income Taxes - Rate reconciliat

Income Taxes - Rate reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Taxes
Income tax provision at federal statutory rate	$ (274)	$ (204)
Add (deduct) effect of:
State income taxes, net of federal tax	(86)	(65)
Expiration of federal research and development credits	1,039	416
Expiration of capital loss carryforwards	0
Change in valuation allowance	(672)	(141)
Income tax provision	$ 7	$ 6

Income Taxes - Deferred (Detail

Income Taxes - Deferred (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets:
Federal and state net operating loss carryforward	$ 23,398	$ 23,030
Research and development credits carryforward	14,795	15,835
Total gross deferred tax assets	38,193	38,865
Less valuation allowance	(38,193)	(38,865)
Net deferred tax assets	$ 0	$ 0

Income Taxes - Additional infor

Income Taxes - Additional information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Income Taxes [Line Items]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate	21.00%	21.00%
Net loss for year	$ (1,311)	$ (979)
Net operating losses carry forwards	20 years
Operating Loss Carryforwards	$ 103,000
Tax Credit Carryforward, Limitations on Use	net operating losses generated in tax years beginning after December 31, 2017 have an unlimited carryforward period, and the amount of net operating loss allowed to be utilized each year is limited to 80% of taxable income
Tax Credit Carryforward Amount	$ 14,800
Operating Loss Carryforwards, Limitation on Annual Utilization	80
Net Operating Loss Carry-Forwards Limitation On Annual Utilization	$ 103,000
Income Taxes Receivable, Current		485
Income Taxes Receivable, Noncurrent		$ 485
Research Tax Credit Carryforward [Member]
Income Taxes [Line Items]
Tax Credit Carryforward, Limitations on Use	The Company has remaining R&D credit carryforwards of approximately $14.8 million that expire in the years 2021 through 2029
Domestic Tax Authority [Member]
Income Taxes [Line Items]
Operating Loss Carryforwards	$ 100,600
Domestic Tax Authority [Member] \| Research Tax Credit Carryforward [Member]
Income Taxes [Line Items]
Tax Credit Carryforward Amount	1,000
NJ State [Member]
Income Taxes [Line Items]
Operating Loss Carryforwards	25,200
State and Local Jurisdiction [Member]
Income Taxes [Line Items]
Operating Loss Carryforwards	$ 1,200

Section 382 Rights Plan (Detail

Section 382 Rights Plan (Details) $ / shares in Units, $ in Millions	Aug. 14, 2020Vote$ / sharesshares	Dec. 31, 2020USD ($)$ / shares	Dec. 31, 2019$ / shares
Preferred stock, par value (in dollars per share) \| $ / shares		$ 0.01	$ 0.01
Amount of operating loss carry forward \| $		$ 103
Section 382 Rights Plan
Rights per share distributed as dividend \| shares	1
Number of preferred stock purchase right for each common stockholder \| shares	1
Section 382 Rights Plan \| Series A-1 Junior Participating Preferred Stock
Number of preferred stock eligible for each warrant become exercisable \| shares	1
Preferred stock, par value (in dollars per share) \| $ / shares	$ 0.01
Purchase price per right \| $ / shares	$ 1.20
Number of votes for fractional share \| Vote	1

Rights Offering (Details)

Rights Offering (Details) - USD ($) $ / shares in Units, $ in Millions	Oct. 09, 2020	Sep. 01, 2020	Dec. 31, 2020	Dec. 31, 2019
Class of Warrant or Right [Line Items]
Preferred stock, par value (in dollars per share)			$ 0.01	$ 0.01
Number of preferred shares outstanding			0	0
Common stock, shares outstanding			74,214,603	44,214,603
Series C Preferred Stock
Class of Warrant or Right [Line Items]
Liquidation preference per share of preferred stock			$ 12
Rights Offering
Class of Warrant or Right [Line Items]
Subscription price per unit of a right		$ 1,090
Number of preferred stock eligible for each warrant become exercisable		1
Number of subscription rights to be held for purchase of a unit		1,105
Number of units entitled for 1,105 subscription rights held		1
Rights Offering \| Series C Preferred Stock
Class of Warrant or Right [Line Items]
Preferred stock, par value (in dollars per share)		$ 0.01
Number of common shares for unit		750
Percentage of dividend on liquidation preference to be paid in cash		3.00%
Liquidation preference per share of preferred stock		$ 1,000	$ 1,012
Annual increase in percentage of the liquidation preference per share, if dividend not paid in cash		5.00%
Rights Offering \| Investment Agreement \| Icahn Capital LP \| Series C Preferred Stock
Class of Warrant or Right [Line Items]
Number of units sold	40,000
Number of preferred shares outstanding	40,000
Common stock, shares outstanding	74,214,603
Issued and gross proceeds	$ 43.6

Series C Preferred Stock - Addi

Series C Preferred Stock - Additional Information (Details) - Series C Preferred Stock - USD ($)	1 Months Ended	12 Months Ended
	Oct. 31, 2020	Dec. 31, 2020
Stock Issued During Period, Shares, New Issues	40,000
Stock Issued During Period, Value, New Issues	$ 40,000,000
Preferred Stock, Liquidation Preference Per Share		$ 12
Preferred Stock, Liquidation Preference Percent		5.00%
Preferred Stock, Liquidation Preference, Value		$ 460,000
Preferred Stock Cumulative Liquidation Value		$ 40,460,000