SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 10)*

Enzon Pharmaceuticals, Inc.

(Name of Issuer)

Common Stock, Par Value $0.01

(Title of Class of Securities)

293904108

(CUSIP Number)

Jesse Lynn, Esq.

Icahn Capital LP

767 Fifth Avenue, 47^th Floor

New York, New York 10153

(212) 702-4300

(Name, Address and Telephone Number of Person Authorized to

Receive Notices and Communications)

December 8, 2016

(Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of Section 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box / /.

NOTE: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See Rule 13d‑7 for other parties to whom copies are to be sent.

*The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

SCHEDULE 13D

Item 1.  Security and Issuer

This statement constitutes Amendment No. 10 to the Schedule 13D relating to the shares of Common Stock, par value $0.01 per share (the "Shares"), issued by Enzon Pharmaceuticals, Inc., a Delaware corporation (the "Issuer"), and amends the Schedule 13D relating to the Shares filed on March 14, 2008 and amended by Amendment Nos. 1 through 9 thereto (as amended, the "Original 13D"), on behalf of the Reporting Persons (as defined in the Original 13D). Capitalized terms used herein and not otherwise defined have the respective meanings ascribed thereto in the Original 13D.

Item 6 of the Original 13D is hereby amended by adding the following:

On December 8, 2016, the Reporting Persons entered into a standstill agreement with the Issuer, pursuant to which the Reporting Persons agreed that neither they nor any of their respective affiliates or associates will acquire any additional Shares, provided that if the Reporting Persons, together with all affiliates and associates thereof, become the beneficial owner of less than 4.99% of the then outstanding Shares, none of the Reporting Persons will be prohibited from acquiring additional Shares so long as the Reporting Persons, together with all affiliates and associates thereof, do not at any time become the beneficial owner of 4.99% or more of the then outstanding Shares.

SIGNATURE

After reasonable inquiry and to the best of each of the undersigned knowledge and belief, each of the undersigned certifies that the information set forth in this statement is true, complete and correct.

Dated: December 8, 2016

ICAHN PARTNERS MASTER FUND LP

ICAHN OFFSHORE LP

ICAHN PARTNERS LP

ICAHN ONSHORE LP

BECKTON CORP.

HOPPER INVESTMENTS LLC

BARBERRY CORP.

HIGH RIVER LIMITED PARTNERSHIP

By: Hopper Investments LLC, general partner

By: Barberry Corp.

Name: Edward E. Mattner

Title: Authorized Signatory

ICAHN CAPITAL LP

By: IPH GP LLC, its general partner

By: Icahn Enterprises Holdings L.P., its sole member

By: Icahn Enterprises G.P. Inc., its general partner

IPH GP LLC

By: Icahn Enterprises Holdings L.P., its sole member

By: Icahn Enterprises G.P. Inc., its general partner

ICAHN ENTERPRISES HOLDINGS L.P.

By: Icahn Enterprises G.P. Inc., its general partner

ICAHN ENTERPRISES G.P. INC.

Name: SungHwan Cho

Title: Chief Financial Officer

CARL C. ICAHN

[Signature Page of Amendment No. 10 to Schedule 13D – Enzon Pharmaceuticals, Inc.]