false --12-31 2023 FY 0000727510 false

 0000727510

 2023-01-01
 2023-12-31

 0000727510

 2023-06-30

 0000727510

 2024-04-18

 ENZN

 UNITED STATES

 SECURITIES AND EXCHANGE COMMISSION

 Washington, D.C. 20549

 FORM 10-K/A

 (Amendment No. 1)

 x

 ANNUAL REPORT PURSUANT TO SECTION 13
 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

 For the Fiscal Year Ended December 31,
2023

 OR

 TRANSITION REPORT PURSUANT
 TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

 For the transition period from
to

 Commission file number: 001-36435

 Enzon
Pharmaceuticals, Inc.

 (Exact name of registrant as specified in its
charter)

 Delaware

 22-2372868

 (State or other jurisdiction
 of incorporation or organization)

 (I.R.S. Employer Identification
 No.)

 20 Commerce Drive (Suite
 135), Cranford, New Jersey

 07016

 (Address of principal executive
 offices)

 (Zip Code)

 Registrant's telephone number, including
area code: ( 732) 980-4500

 Securities registered pursuant to Section 12(b) of
the Act:

 Title
 of Each Class

 Trading
 Symbol(s)

 Name
 of Each Exchange on Which Registered

 None

 N/A

 N/A

 Securities registered pursuant to Section
12(g) of the Act:

 Common Stock, $0.01 par value

 Series A-1 Junior Participating Preferred
Stock Purchase Rights

by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.
Yes x No

by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Exchange
Act. Yes x No

by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Exchange
Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports),
and (2) has been subject to such filing requirements for the past 90 days. x Yes No

by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant
to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period
that the registrant was required to submit such files). x Yes No

 Indicate by check mark whether the registrant
is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company.
See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company"
and "emerging growth company" in Rule 12b-2 of the Exchange Act:

 Large accelerated filer

 Accelerated filer

 Non-accelerated filer x

 Smaller reporting company x

 Emerging growth company

 If an emerging growth company, indicate by check
mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting
standards provided pursuant to Section 13(a) of the Exchange Act.

 Indicate by check mark whether the registrant
has filed a report on and attestation to its management's assessment of the effectiveness of its internal control over financial
reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that
prepared or issued its audit report.

 If securities are registered pursuant to Section 12(b) of
the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an
error to previously issued financial statements.

 Indicate by check mark whether any of those error
corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant's
executive o cers during the relevant recovery period pursuant to §240.10D-1(b).

by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act).
Yes x No

 The aggregate
market value of the Common Stock, $0.01 par value per share (the "Common Stock"), held by non-affiliates of the
registrant was approximately $ 7,591,503 as of June 30, 2023, based upon the closing sale price quoted on the OTCQX market of
the OTC Markets Group, Inc. of $0.20 per share reported for such date. Shares of Common Stock held by each executive officer
and director and certain beneficial owners of 10% or more of the Common Stock of the registrant as of June 30, 2023 have been
excluded in that such shares may be deemed to be owned by affiliates. This determination of affiliate status is not necessarily a
conclusive determination for other purposes.

 There were
 74,214,603 shares of Common Stock issued and outstanding as of April 19, 2024.

 DOCUMENTS INCORPORATED BY REFERENCE

 None.

 Auditor Name
 Auditor Firm ID
 Auditor Location

 EisnerAmper LLP
 Philadelphia, Pennsylvania

 ENZON PHARMACEUTICALS, INC.

 2023 Annual Report on
Form 10-K/A

 (Amendment No. 1)

 Page

 Explanatory Note

 Item 10.

 Directors, Executive Officers and Corporate Governance

 Item 11.

 Executive Compensation

 Item 12.

 Security Ownership of Certain Beneficial Owners and
 Management and Related Stockholder Matters

 Item 13.

 Certain Relationships and Related Transactions, and
 Director Independence

 Item 14.

 Principal Accounting Fees and Services

 Item 15.

 Exhibits, Financial Statement Schedules

 EXPLANATORY NOTE

 Enzon Pharmaceuticals, Inc.
(the "Company," "we," "us," or "our") is filing this Amendment No. 1 on Form 10-K/A
(this "Amendment No. 1") to amend our Annual Report on Form 10-K for the year ended December 31, 2023, originally filed with the Securities and Exchange Commission (the "SEC") on March 20, 2024 (our "Annual Report"), to
include the information required by Items 10 through 14 of Part III of Form 10-K. This information was previously omitted from
our Annual Report in reliance on General Instruction G(3) to Form 10-K, which permits the information in the above referenced
items to be incorporated in the Form 10-K by reference from our definitive proxy statement if such statement is filed no later than
120 days after our fiscal year-end. We are filing this Amendment No. 1 to provide the information required in Part III of Form 10-K
because a definitive proxy statement containing such information will not be filed by the Company within 120 days after the end of the
fiscal year covered by the Form 10-K.

 Pursuant to the rules of the SEC, Part IV, Item
15 has also been amended to contain the currently dated certification from the Company's principal executive officer who is also
the Company's principal financial officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002. The certification of the
Company's principal executive officer and principal financial officer is attached to this Amendment No. 1 as Exhibit 31.1.
Because no financial statements have been included in this Amendment No. 1 and this Amendment No. 1 does not contain or amend
any disclosure with respect to Items 307 and 308 of Regulation S-K, paragraphs 3, 4 and 5 of the certifications
have been omitted. Additionally, we are not including currently dated certifications required under Section 906 of the Sarbanes-Oxley
Act of 2002 as no financial statements are being filed with this Amendment No. 1.

 This Amendment No. 1
does not amend any other information set forth in our Annual Report, and we have not updated disclosures included therein to reflect
any subsequent events. This Amendment No. 1 should be read in conjunction with our Annual Report and with our filings with the SEC
subsequent to our Annual Report.

 PART III.

 Item 10. Directors, Executive Officers and
Corporate Governance

 The following table sets forth
certain information concerning our executive officers and directors as of April 26, 2024.

 Nominee Name

 Age

 Director/Officer

 Since

 Position with Our Company

 Randolph C. Read

 2020

 Chairman of the Board

 Jordan Bleznick

 2020

 Director

 Jaffery (Jay) A. Firestone

 2022

 Director

 2021

 Chief Executive Officer, Chief Financial Officer, and Secretary

 Directors

 Randolph C. Read – Mr. Read
has been a director of our Company since August 2020, and since that time has served as our Chairman of the Board and Chairman of
the Finance and Audit Committee. Mr. Read has been President and Chief Executive Officer of Nevada Strategic Credit Investments,
LLC since 2009. Mr. Read has served since November 2018 as an independent manager/director and Chairman of the Board of Managers
of New York REIT Liquidating, LLC, a successor to New York REIT, Inc., a publicly traded (NYSE) real estate investment trust, where
Mr. Read served as an independent director from December 2014 to November 2018, including as Chairman of its Board of Directors
from June 2015 to November 2018. Mr. Read has served as an independent Director of SandRidge Energy, Inc. (NYSE),
an oil and natural gas exploration and production company, since June 2018. Mr. Read previously served as an independent director
of Luby's Inc. from August 2019 to August 2021. Mr. Read has previously served as President of a variety of other
companies and has previously served on a number of public and private company boards. Mr. Read is admitted as a Certified Public
Accountant and has an M.B.A. in Finance from the Wharton Graduate School of the University of Pennsylvania and a B.S. from Tulane University.
Mr. Read's qualifications to serve as a director of our Company include his significant business experience as a director and
an executive officer of entities in a variety of industries, as well as capital markets, governance, and operations experience, in addition
to his knowledge, financial expertise and leadership qualities and roles.

 Jordan
Bleznick – Mr. Bleznick has been a director of our Company since August 2020. From April 2002 through
his retirement in April 2023, Mr. Bleznick was the Vice President/Taxes of Starfire Holding Corporation, a privately-held holding
company controlled by Carl C. Icahn. From April 2002 through his retirement in April 2023, he was the Chief Tax Counsel for
various affiliates of Mr. Icahn. In March 2023, Mr. Bleznick was appointed as a director and Chairman of the Board of
the general partner of CVR Partners, LP, a nitrogen fertilizer company controlled by Mr. Icahn. From April 2021 until April 2023,
Mr. Bleznick was a director of various other affiliates of Mr. Icahn, including American Entertainment Properties Corp., which
is the primary operating subsidiary of Icahn Enterprises L.P. From March 2000 through March 2002, Mr. Bleznick was a partner
in the New York City office of the law firm of DLA Piper. From March 1984 until February 2000, he was an associate and then
a partner at the New York City law firm of Gordon Altman Weitzen Shalov and Wein. Mr. Bleznick received a B.A. in Economics from
the University of Cincinnati, a J.D. from The Ohio State University College of Law and a L.L.M. in Taxation from the New York University
School of Law. Mr. Bleznick's qualifications to serve as a director of our Company include his expertise in tax law and his involvement
with other public companies owned by Carl C. Icahn and affiliated entities.

 Jaffery
(Jay) A. Firestone – Mr. Firestone has been a director of our Company since June 2022. He has served
as Chairman and Chief Executive Officer at Prodigy Pictures Inc., a producer of film, television and cross-platform media, since 2006.
Previously, Mr. Firestone established Fireworks Entertainment in 1996 to produce, distribute and finance television programs and
feature films. In 1998, Fireworks Entertainment was acquired by CanWest Global Communications Corporation and Mr. Firestone was
named chairman and chief executive officer and oversaw the company's Los Angeles and London based television operations as well
as its Los Angeles feature film division, Fireworks Pictures. In addition, Mr. Firestone oversaw the company's interest in
New York based IDP Distribution, an independent distribution and marketing company formed by Fireworks Entertainment in 2000 as a joint
venture with Samuel Goldwyn Films and Stratosphere Entertainment. Mr. Firestone has served on the board of directors for the Academy
of Canadian Cinema and Television and the Academy of Television Arts and Sciences International Council in Los Angeles. Mr. Firestone
has led two initial public offerings. Mr. Firestone has been a director of CVR Energy, Inc. (NYSE), a diversified holding company
primarily engaged in the renewables, petroleum refining and marketing business, since April 2020 and SandRidge Energy, Inc.
(NYSE) since May 2021, and previously served as a director of Voltari Corporation, a commercial real estate company, from July 2011
through September 2019. Mr. Firestone obtained a degree in commerce from McMasters University. Mr. Firestone's qualifications
to serve as a director of our Company include his extensive experience in dealing with financial reporting and his past service on other
public company boards.

 Management

 Richard
L. Feinstein – Mr. Feinstein has served as our Chief Executive Officer, Chief Financial Officer, and
Secretary since February 2021, having previously served as Vice President-Finance and Chief Financial Officer since March 2016.
Prior to that, Mr. Feinstein served as our Vice President – Finance and Principal Financial Officer since December 2013.
Mr. Feinstein is a retired partner of KPMG LLP and currently a private consultant providing management and financial advice to clients
in a variety of industries. From 2015 to 2019, he provided financial consulting services to General Cannabis Corp, a public company.
During July 2016, he provided consulting services to Hamaspik, Inc. From September 2010 to July 2013, as a consultant,
he was the Chief Financial Officer of Ameritrans Capital Corporation. From April 2004 to December 2004, Mr. Feinstein,
as a consultant, served as Chief Financial Officer for Image Technology Laboratories, Inc., a developer and provider of radiological
imaging, archiving and communications systems. From December 1997 to October 2002, Mr. Feinstein was Senior Vice-President
and Chief Financial Officer for The Major Automotive Companies, Inc., formerly a diversified holding company, but now engaged solely
in retail automotive dealership operations. Mr. Feinstein has served on boards of both publicly- held and not-for-profit enterprises.
Mr. Feinstein previously served as a board member and chair of the audit committee of MKTG, Inc.; a board member and chief
financial officer of the not-for-profit USA Fitness Corps; a board member and chair of the audit committee of EDGAR Online, Inc.;
a board member and chair of the finance committee of the New York Road Runners; and a member of the executive committee of the Association
for a Better New York. Mr. Feinstein, a certified public accountant, received a BBA degree from Pace University. Mr. Feinstein
also served in the United States Marine Corps.

 Director Independence

 Although our Common Stock is no longer listed
on The Nasdaq Stock Market ("Nasdaq"), our Board of Directors (the "Board"), continues to use the definition of
independence set forth in the listing standards of Nasdaq in evaluating the independence of our directors. Our Board has determined that
each of Messrs. Read, Bleznick and Firestone is independent as defined by the listing standards of Nasdaq.

 Meetings and Attendance

 Our Board held five meetings during fiscal year
2023. Each current director who served on the Board during fiscal year 2023 attended at least 75% of the total number of meetings held
during fiscal year 2023 by our Board and committees of our Board of which such director was a member (during the period that the director
served).

 We do not have a policy requiring our directors
to attend our annual stockholders' meetings. All of our then-serving directors attended the 2023 annual meeting.

 Board Leadership Structure

 Our Board is led by a Chairman appointed by our
Board annually. The Chairman leads our Board in its role of providing advice to, and overseeing the performance of, our Chief Executive
Officer. Randolph C. Read currently serves as the Chairman of the Board and Richard L. Feinstein currently serves as our Chief Executive
Officer. Our Board does not have a formal policy with respect to the separation of the positions of Chairman and Chief Executive Officer.
However, our Board believes that separating these positions allows the Chief Executive Officer to focus on day-to-day operations, while
allowing the Chairman to lead our Board in its primary role of review and oversight of management.

 Hedging or Pledging of Company Stock

 Our Company maintains a policy prohibiting our
employees, officers and directors from engaging in hedging or pledging transactions involving Company stock or holding Company stock
in a margin account.

 Communications with Directors

 Stockholders may communicate directly with our
directors. All communications should be sent in care of our Secretary at our address and should prominently indicate on the outside of
the envelope that it is intended for our Board or for a specific director. If no director is specified, the communication will be forwarded
to the entire Board.

 Standing Committees of our Board

 During 2023, the only standing committee of the Board was the Finance
and Audit Committee.

 Finance and Audit Committee

 Our Finance and Audit Committee is currently
comprised of Mr. Read, who has also served as Chairman of the committee since August 2020, and Mr. Firestone. Our Finance
and Audit Committee held four meetings during fiscal year 2023.

 In evaluating the composition of our Finance
and Audit Committee, our Board has determined that each current member is, and during 2023 all members were, independent as defined by
the listing standards of Nasdaq and Rule 10A-3 under the Exchange Act. Our Board has determined that Mr. Read satisfies the
definition of "audit committee financial expert" within the meaning of Item 407(d)(5) of Regulation S-K.

 The
primary purpose of the Finance and Audit Committee is to monitor the integrity of our Company's financial reporting process and
financial statements, the systems of internal controls and controls over financial reporting, our Company's compliance with legal
and regulatory requirements, and the performance and independence of our Company's independent registered public accounting firm.
The Finance and Audit Committee is responsible for discussing with management the adequacy of our Company's internal controls and
the financial reporting process. The Finance and Audit Committee also is responsible for discussing these matters with our Company's
independent registered public accounting firm. In addition, the Finance and Audit Committee is responsible for reviewing our financial
statements and discussing them with management and our Company's independent registered public accounting firm before those financial
statements are filed with the SEC. The charter of the Finance and Audit Committee may be found on the Corporate Governance page of
our website at www.enzon.com.

 Other Board Committees

 Currently, we do not have a nominating committee
or a compensation committee, and the Board is of the view that it is not necessary to have such committees at this time because the Board
is currently composed of only three members, all of whom are independent as defined by the listing standards of Nasdaq. Our Board directly
performs the functions of a nominating committee and oversees the process by which individuals may be nominated to our Board. The Board
also directly performs the functions of a compensation committee and oversees the process by which our named executive officer, who is
a consultant, and directors are compensated. We currently have no employees.

 Our Board's Role in Risk Oversight

 We, like other companies, face a variety of risks,
including operational, financial, regulatory, legal, and information technology and cybersecurity. While our Board oversees risk management,
our executive officer is responsible for day-to-day risk management and provides updates to our Board as appropriate regarding risk management
activities. Risk oversight is a significant component in all major Board decisions and the evaluation of risk is an important element
in our Board's decision-making process. Our Board believes that the processes it has established for overseeing risk would be effective
under a variety of leadership frameworks and therefore do not materially affect its choice of leadership structure as described above.

 Code of Conduct

 Our Board has adopted a code of conduct that is
applicable to all of our directors and executive officers. Any material changes made to the code of conduct or any waivers granted to
any of our directors and executive officers will be publicly disclosed on our website at www.enzon.com within four business days of such
material change or waiver. A copy of our code of conduct is available on the Corporate Governance page of our website at www.enzon.com.

 Item 11. Executive Compensation

 Summary Compensation Table

 Name
 and Principal
 Position

 Year

 Salary

 ($)

 Bonus

 ($)

 Stock

 Awards
 ($)

 Option

 Awards

 ($)

 All
 Other
 Compensation
 ($)(1)

 Total

 ($)

 Richard
 L. Feinstein

Chief Executive Officer, Chief

 2023

 —

 15,000

 —

 —

 209,068

 224,068

 Financial Officer
 and Secretary

 2022

 —

 10,000

 —

 —

 199,452

 209,452

 (1) The amounts in this column reflect fees and expenses related
to services rendered during fiscal years 2023 and 2022 on a consulting basis. Mr. Feinstein did not receive a base salary
for fiscal year 2023 or 2022.

 Narrative Disclosure to Summary
Compensation Table

 On February 24, 2022, the
Company entered into a revised consulting agreement with Richard L. Feinstein, the Company's Chief Executive Officer, Chief Financial
Officer and Secretary. The agreement provides for Mr. Feinstein's consulting fee to be set at $200,000 per year and an incentive
of up to 25% of the fee at the discretion of our Board based on the Company's and Mr. Feinstein's performance. In 2023,
the Board agreed to increase Mr. Feinstein's consulting fee to $210,000.

 Outstanding Equity Awards at December 31, 2023

 None. The 2011 Stock Option Plan and Incentive
Plan was terminated effective February 24, 2022 and, as such, there will be no further grants made pursuant to such plan.

 Potential Payments Upon Termination or Change in Control

 Mr. Feinstein is not covered by a severance
or change in control agreement and, accordingly, he would not have been entitled to receive any termination or change in control-related
payments as of December 31, 2023.

 Amended and Restated 2013 Outside Director Compensation Plan

 Under the Amended and Restated 2013 Outside Director
Compensation Plan, each non-employee director (i) received an annual cash retainer of $30,000 for service on the Board, (ii) for
service as chair of the Finance and Audit Committee, received an additional annual cash retainer of $10,000 and (iii) for service
as a non-chair member of the Finance and Audit Committee, received an additional annual cash retainer of $5,000.

 Currently, in lieu of the above, each director
is compensated in the amount of $36,666 per annum (pro-rated for partial periods of service). The one-fourth of the annual cash compensation
is payable quarterly at the end of each quarter.

 Total Director Compensation

 A summary of compensation paid to each of our
directors during fiscal year 2023 is set forth below:

 Name

 Fees Earned
 or Paid in
 Cash
 ($)

 Stock
 Awards
 ($)(1)

 Option
 Awards
 ($)(2)

 Total
 ($)

 Randolph C. Read

 —

 —

 Jordan Bleznick

 —

 —

 Jaffery (Jay) A. Firestone

 —

 —

 (1) As of December 31, 2023, none of the directors listed
held any outstanding restricted stock units.

 (2) As of December 31, 2023, none of the directors listed held
any outstanding stock options.

 Item 12. Security Ownership of Certain Beneficial
Owners and Management and Related Stockholder Matters

 The following table sets forth certain information
as of April 19, 2024 concerning stock ownership of (i) each person known by us to own beneficially more than 5% of our
outstanding Common Stock, (ii) each of our directors as of such date, (iii) each of our named executive officers, and (iv) all
of our directors and current executive officers as a group. Information set forth in this table as to our directors and current executive
officers is based upon information supplied by these individuals. Information in this table as to our greater than 5% stockholders is
based solely upon the Schedules 13D or 13G filed by these stockholders with the SEC. Where information is based on a Schedule 13D
or 13G, the number of shares owned is as of the date for which information was provided in such schedules.

 Name of Beneficial
 Owner or Identity of Group(1)

 Amount
 and
 Nature of
 Beneficial
 Ownership(2)

 Percentage
 of
 Voting Stock
 Outstanding(3)

 Randolph C. Read

 200,000

 *

 Jordan Bleznick

 100,000

 *

 Jaffery A. Firestone

 —

 —

 —

 —

 Carl C. Icahn and affiliated entities

 36,056,636
 (4)

 48.6
 %

 Jonathan Couchman and affiliated entities

 7,743,954
 (5)

 10.4
 %

 All Directors and Current Executive Officers as a group (4
 persons)

 300,000

 *

 * Less than one percent

 (1) The address for each of the named executive officers and
directors listed in this table is c/o Enzon Pharmaceuticals, Inc., 20 Commerce Drive, Suite 135, Cranford, New
Jersey, 07016.

 (2) Beneficial ownership is determined in accordance with the
rules of the SEC that deem shares to be beneficially owned by any person who has or shares voting or investment power with
respect to such shares. Unless otherwise indicated below, the persons and entities named in the table have sole voting and sole
investment power with respect to all the shares beneficially owned, subject to community property laws where applicable.

 (3) Based on 74,214,603 shares of Common Stock, which were issued
and outstanding as of the close of business on April 19, 2024. Each share of Common Stock is entitled to one vote.
The percentage of voting stock outstanding for each person set forth in the table is calculated by dividing (i) the number
of shares of Common Stock deemed to be beneficially held by such person as of April 19, 2024 by (ii) the sum of
(A) the number of shares of Common Stock outstanding as of April 19, 2024, plus (B) the number of shares of
Common Stock subject to stock options, if any, held by such person that were exercisable as of April 19, 2024 or will
become exercisable within 60 days after April 19, 2024.

 (4) Information concerning stock ownership was obtained from
Amendment No. 13 to the Schedule 13D filed with the SEC on October 14, 2020 by Carl C. Icahn and various entities
affiliated with him. The address for Carl C. Icahn and entities affiliated with him is 16690 Collins Avenue, Suite PH-1, Sunny
Isles Beach, FL 33160. Mr. Icahn was reported to share voting and dispositive power over all 36,056,636 shares of Common Stock
with entities affiliated with him. In addition, Mr. Icahn, through entities affiliated with him, also reported ownership of
39,277 shares of the Company's Series C Non-Convertible Redeemable Preferred Stock, which represents approximately 98% of
all outstanding shares of Series C Preferred Stock.

 (5) Information concerning stock ownership was obtained from
Amendment No. 2 to the Schedule 13D filed with the SEC on September 17, 2020 and the Form 4 filed
August 17, 2021 by Jonathan Couchman ("Mr. Couchman"), Couchman Family Fund (the "Foundation"),
Xstelos Corp. ("Xstelos") and Myrexis, Inc. ("Myrexis"). Mr. Couchman reported sole voting and
dispositive power over 4,717,666 shares and shared voting and dispositive power over the shares directly held by the Foundation,
Xstelos and Myrexis. The Form 4 reported that the Foundation directly held 350,000 shares, Xstelos directly held 2,043,024
shares, and Myrexis directly held 633,264 shares, and each reported shared voting and dispositive power over such shares. The
principal business address for Mr. Couchman, the Foundation and Myrexis is c/o Couchman Management LLC, 600 Fifth Avenue,
2nd Floor, New York, NY 10020. The principal business address for Xstelos is 1105 North Market Street, Suite 1300, Wilmington,
DE 19801.

 Item 13. Certain Relationships and Related
Transactions, and Director Independence

 Our Board has adopted a formal written policy
that we will not enter into any "related party transaction" (defined consistent with Item 404 of Regulation S-K
under the Exchange Act) unless the Finance and Audit Committee or a comparable committee of disinterested directors approves such transaction.
No member of the Finance and Audit Committee or comparable committee shall participate in the review or approval of any related party
transaction or any material amendment thereto where that member is a related party in that transaction. In reviewing and approving any
related party transaction or any material amendment thereto, the Finance and Audit Committee or comparable committee shall satisfy itself
that it has been fully informed as to the related party's relationship and interest and as to the material facts of the proposed
related party transaction or material amendment, and shall determine that the related party transaction or material amendment thereto
is fair to our Company.

 Since January 1, 2020, there have been no
such related party transactions, other than on September 1, 2020, when we entered into a non-exclusive Investment Agreement with
Icahn Capital LP in connection with our recently completed rights offering. Pursuant to the Investment Agreement, Icahn Capital
LP agreed to subscribe for its pro-rata share of our rights offering and to purchase all units that remained unsubscribed for at
the expiration of our rights offering to the extent that other holders elected not to exercise all of their respective subscription rights.
Before giving effect to the rights offering, Icahn Capital LP, together with its affiliates, beneficially owned approximately 15%
of our Common Stock.

 Pursuant to the rights offering, Icahn Capital
LP, together with its affiliates, subscribed for 5,971 units (its pro-rata share of the rights offering), representing the purchase
of 4,478,250 shares of Common Stock and 5,971 shares of Series C preferred stock. Icahn Capital LP also purchased all units
that remained unsubscribed for at the expiration of the rights offering to the extent that other holders elected not to exercise all
of their respective subscription rights, which totaled 33,306 units, representing the purchase of 24,979,500 shares of Common Stock
and 33,306 shares of Series C preferred stock. Following the completion of the rights offering, Icahn Capital LP, together
with its affiliates, owned approximately 48% of our outstanding Common Stock and approximately 98% of our outstanding Series C preferred
stock.

 No fees were paid by the Company to Icahn Capital
LP in consideration of such investment commitment. In connection with the execution of the Investment Agreement, the parties agreed to
terminate the Standstill Agreement, dated December 18, 2016, by and between the Company, Icahn Capital LP and the other affiliated
parties identified therein, so that it is of no further force or effect; and waived the applicability of Section 203 of the Delaware
General Corporation Law of the State of Delaware to Icahn Capital LP and its affiliates. In addition, we agreed to use our best efforts
to register for resale all of the shares of our Common Stock held by Icahn Capital LP and its affiliates following the closing of our
rights offering. We filed a resale registration statement covering the resale of the shares on November 12, 2020, which became effective
on November 23, 2020.

 Item 14. Principal Accounting Fees and Services

 Audit Fees, Audit-Related Fees, Tax Fees and All Other Fees

 The following table sets forth the aggregate
fees paid or payable for services provided to us by EisnerAmper LLP for professional services rendered for the fiscal years ended
December 31, 2023 and 2022. The Finance and Audit Committee considered whether the provision of these services by EisnerAmper LLP
was compatible with maintaining the firm's independence and concluded that EisnerAmper LLP was "independent."

 EisnerAmper LLP

 Fiscal Year

 Ended
 December 31, 2023

 Fiscal Year

 Ended
 December 31, 2022

 Audit Fees(1)

 $
 115,500

 $
 107,100

 Audit-Related Fees

 —

 —

 Tax Fees(2)

 $
 8,925

 $
 8,925

 All Other Fees

 —

 —

 Total

 $
 124,425

 $
 116,025

 (1) For fiscal years 2023 and 2022, "Audit Fees"
paid or payable to EisnerAmper LLP related to services in connection with the audit of our annual consolidated financial statements,
review of quarterly financial statements, issuance of consents, review of documents filed with the SEC and accounting
consultations.

 (2) For fiscal years 2023 and 2022, "Tax Fees"
paid or payable to EisnerAmper LLP related to tax preparation services and tax consulting services.

 Item 15. Exhibits, Financial Statement Schedules

 (a) (1)

 Financial Statements. The financial statements included
in "Item 8. Financial Statements and Supplementary Data" are filed as part of the Annual Report.

 (a) (2)

 Financial Statement Schedules. There are no financial
 statement schedules filed as part of this Amendment No. 1, since the required information is included in the financial statements,
 including the notes thereto, included in "Item 8. Financial Statements and Supplementary Data" of the Annual Report.

 (a) (3)

 Exhibits. (see "Exhibit Index" below).

 (b)

 Refer to (a)(3).

 (c)

 Not applicable.

 EXHIBIT INDEX

 Exhibit

 Reference

 Number

 Description

 No.

 3.1

 Amended and Restated Certificate of Incorporation dated May 18, 2006, together with that Certificate of Amendment to the Amended and Restated Certificate of Incorporation dated July 13, 2010

 (1)

 3.2

 Second Amended and Restated By-Laws effective March 11, 2011, as amended by Amendment No. 1 to the Second Amended and Restated By-Laws effective February 15, 2013

 (2)

 3.3

 Certificate of Designation of Series A-1 Junior Participating Preferred Stock of Enzon Pharmaceuticals, Inc. filed with the Secretary of State of the State of Delaware on August 14, 2020

 (4)

 3.4

 Certificate of Designation of Series C Non-Convertible Redeemable Preferred Stock of Enzon Pharmaceuticals, Inc., filed with the Secretary of State of the State of Delaware on September 21, 2020

 (5)

 3.5

 First Amendment to the Second Amended and Restated By-Laws, effective February 24, 2022

 (10)

 4.1

 Description of Enzon Pharmaceuticals, Inc.'s Registered Securities

 (12)

 4.2

 Section 382 Rights Agreement, dated as of August 14, 2020, by and between Enzon Pharmaceuticals, Inc. and Continental Stock Transfer & Trust Company, which includes the Form of Certificate of Designation as Exhibit A, Form of Rights Certificate as Exhibit B and the Form of Summary of Rights as Exhibit C

 (4)

 4.3

 First Amendment to the Section 382 Rights Agreement, dated as of June 4, 2021 and effective as of June 2, 2021, by and between Enzon Pharmaceuticals, Inc. and Continental Stock Transfer & Trust Company.

 (6)

 10.1

 Development, License and Supply Agreement between Enzon, Inc. (now known as Enzon Pharmaceuticals, Inc.) and Schering Corporation dated November 14, 1990, as amended*

 (3)

 10.2

 Amended and Restated 2013 Outside Director Compensation Plan**

 (7)

 10.3

 Amended and Restated Exclusive IP Marketing Agreement, dated as of June 28, 2004, by and between Micromet AG and Enzon Pharmaceuticals, Inc.

 (8)

 10.4

 Letter Agreement, dated January 30, 2019, between Servier IP UK Limited and Enzon Pharmaceuticals, Inc.

 (8)

 10.5

 Investment Agreement, dated as of September 1, 2020, by and between Enzon Pharmaceuticals, Inc. and Icahn Capital LP

 (9)

 10.6

 Independent Contractor Agreement, effective as of February 24, 2022, between Enzon Pharmaceuticals, Inc. and Richard L. Feinstein **

 (10)

 10.7

 Form of Indemnification Agreement for members of the Board of Directors **

 (11)

 21.1

 Subsidiaries of Registrant

 (12)

 23.1

 Consent of EisnerAmper LLP

 (12)

 31.1

 Certification of Principal Executive Officer and Principal Financial Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002

 +

 32.1

 Certification of Principal Executive Officer and Principal Financial Officer pursuant to Section 906 of the Sarbanes-Oxley Act of 2002***

 (12)

 101.INS

 (12)

 101.SCH

 (12)

 101.CAL

 Linkbase Document

 (12)

 101.LAB

 Document

 (12)

 101.PRE

 Linkbase Document

 (12)

 101.DEF

 Linkbase Document

 (12)

 Cover Page Interactive

 (12)

 (12)

 + Filed
herewith

 *

 Portions of this exhibit have been redacted and filed
 separately with the SEC pursuant to a confidential treatment request.

 **

 Management contracts or compensatory plans and arrangements
 required to be filed pursuant to Item 601(b)(10)(ii)(A) or (iii) of Regulation S-K.

 ***

 These certifications are not deemed filed by the SEC
 and are not to be incorporated by reference in any filing the Company makes under the Securities Act of 1933, as amended, or the
 Exchange Act, irrespective of any general incorporation language in any filings.

 Referenced exhibit was previously filed with
the SEC as an exhibit to the Company's filing indicated below and is incorporated herein by reference to that filing:

 (1)

 Quarterly Report on Form 10-Q
 for the quarter ended June 30, 2010 filed August 9, 2010

 (2)
 Annual Report on Form 10-K for the year
 ended December 31, 2012 filed March 18, 2013

 (3)
 Annual Report on Form 10-K for the fiscal
 year ended June 30, 2002 filed on September 26, 2002

 (4)
 Current Report on Form 8-K filed August 14,
 2020

 (5)
 Current Report on Form 8-K filed September 23,
 2020

 (6)
 Current Report on Form 8-K filed June 8,
 2021

 (7)
 Quarterly report on Form 10-Q for the
 quarter ended June 30, 2013 filed August 6, 2013

 (8)
 Annual Report on Form 10-K for the fiscal
 year ended December 31, 2018 filed on February 21, 2019

 (9)
 Current Report on Form 8-K filed September 1,
 2020

 (10)
 Annual Report on Form 10-K for the
 fiscal year ended December 31, 2021 filed on February 25, 2022

 (11)
 Quarterly report on Form 10-Q for the
 quarter ended March 31, 2022 filed April 26, 2022

 (12)
 Annual Report on Form 10-K for the
 fiscal year ended December 31, 2023 filed on March 20, 2024

 SIGNATURES

 Pursuant to the requirements
of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this Amendment No. 1 to
Annual Report on Form 10-K to be signed on its behalf by the undersigned, thereunto duly authorized.

 ENZON
 PHARMACEUTICALS, INC.

 (Registrant)

 Dated: April 26, 2024

 /s/ Richard
 L. Feinstein

 Chief Executive Officer, Chief Financial Officer and
 Secretary

 (Principal Executive Officer and Principal Financial
 Officer)

 Pursuant to the requirements
of the Securities Exchange Act of 1934, this Amendment No. 1 to Annual Report on Form 10-K has been signed below by the following
persons on behalf of the registrant and in the capacities and on the dates indicated.

 Name

 Title

 Date

 /s/ Richard
 L. Feinstein

 Chief Executive Officer, Chief Financial Officer and
 Secretary

 April 26, 2024

 (Principal Executive Officer and Principal Financial
 Officer)

 /s/ Randolph
 C. Read

 Director (Chairman of the Board)

 April 26, 2024

 Randolph C. Read

 /s/ Jordan Bleznick

 Director

 April 26, 2024

 Jordan Bleznick

 /s/ Jaffrey
 (Jay) A. Firestone

 Director

 April 26, 2024

 Jaffrey (Jay) A. Firestone