Enzon Pharmaceuticals (ENZN) completes exchange offer for Series C preferred stock

Rhea-AI Filing Summary

Enzon Pharmaceuticals, Inc. reported that it has completed the exchange offer relating to its Series C Non-Convertible Redeemable Preferred Stock. The company disclosed this by issuing a press release, which is included as an exhibit to the report and incorporated by reference.

The information and attached press release are being furnished rather than filed, meaning they are not subject to certain liability provisions under the Exchange Act or automatically incorporated into other securities law filings unless specifically referenced.

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): March 25, 2026

ENZON PHARMACEUTICALS, INC.

(Exact name of registrant as specified in its charter)

Delaware (State or other jurisdiction
of incorporation) 000-12957 (Commission File Number) 22-2372868 (IRS Employer Identification No.)

20 Commerce Drive (Suite 135), Cranford, New Jersey (Address of principal executive offices) 07016 (Zip Code)

(732) 980-4500

(Registrant’s telephone number, including area code)

Not Applicable

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

x Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

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

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

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.  ¨

Item 7.01 Regulation FD Disclosure.

On March 25, 2026, Enzon Pharmaceuticals, Inc. issued a press release announcing the completion of the exchange offer relating to its Series C Non-Convertible Redeemable Preferred Stock. A copy of the press release is attached as Exhibit 99.1 hereto and incorporated herein by reference.

In accordance with General Instruction B.2 of Form 8-K, the foregoing information, including Exhibit 99.1, shall not be deemed “filed” for the purposes of Section 18 of the Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall such information, including Exhibit 99.1, be deemed incorporated by reference into any filing under the Securities Act or the Exchange Act, except as shall be expressly set forth by specific reference in such filing.

Item 9.01 Financial Statements and Exhibits. 

(d) Exhibits.

Exhibit		Description
99.1		Press Release issued by Enzon Pharmaceuticals, Inc., dated March 25, 2026 (incorporated by reference to Exhibit (a)(1)(L) to Amendment No. 9 to the Schedule TO-I/A filed by Enzon with the SEC on March 25, 2026).
104		Cover Page Interactive Data File (embedded within the Inline XBRL document).

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	ENZON PHARMACEUTICALS, INC.
	(Registrant)
Date: March 25, 2026
	By:	/s/Richard L. Feinstein
	Name:	Richard L. Feinstein
	Title:	Chief Executive Officer, Chief Financial Officer and Secretary

FAQ

What did Enzon Pharmaceuticals (ENZN) announce in this Form 8-K?

Enzon Pharmaceuticals announced the completion of its exchange offer for Series C Non-Convertible Redeemable Preferred Stock. The details are described in a press release attached as Exhibit 99.1 and incorporated into the report by reference.

Which security is affected by Enzon Pharmaceuticals’ (ENZN) exchange offer?

The exchange offer relates to Enzon Pharmaceuticals’ Series C Non-Convertible Redeemable Preferred Stock. The Form 8-K notes that the exchange offer has been completed and refers investors to the accompanying press release for additional information.

How did Enzon Pharmaceuticals (ENZN) communicate the completion of the exchange offer?

Enzon Pharmaceuticals communicated the completion of the exchange offer through a press release. This press release is attached to the Form 8-K as Exhibit 99.1 and is incorporated into the report by reference for investors seeking more detail.

Is the Enzon Pharmaceuticals (ENZN) press release considered filed for liability purposes?

The press release and related information are furnished, not filed, for Exchange Act purposes. This means they are not subject to Section 18 liability and are only incorporated into other filings when specifically referenced by Enzon Pharmaceuticals.

Does Enzon Pharmaceuticals (ENZN) list any securities on a national exchange in this report?

The report indicates there are no securities of Enzon Pharmaceuticals listed under Section 12(b), showing “None” under the title of each class and “N/A” for trading symbol and exchange, consistent with the included securities registration table.

Filing Exhibits & Attachments

3 documents

Other Documents

• EX-101 XBRL TAXONOMY EXTENSION SCHEMA 2.9 KB
• EX-101 XBRL TAXONOMY EXTENSION LABEL LINKBASE 33.4 KB
• EX-101 XBRL TAXONOMY EXTENSION PRESENTATION LINKBASE 21.8 KB