8-K
Viskase Holdings, Inc. (ENZN)
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): September 30, 2025
ENZON PHARMACEUTICALS, INC.
(Exact name of registrant as specified in its charter)
| Delaware<br><br> <br>(State or other jurisdiction<br><br> of incorporation) | 001-36435<br><br> <br>(Commission File Number) | 22-2372868<br><br> <br>(IRS Employer Identification No.) |
|---|---|---|
| 20 Commerce Drive (Suite 135), Cranford, New Jersey<br><br> <br>(Address of principal executive<br> offices) | 07016<br><br> <br>(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:
| ¨ | 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)) |
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| ¨ | Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) |
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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 1.01 | Entry into a Material Definitive Agreement. |
|---|
On September 30, 2025, Enzon Pharmaceuticals, Inc. (the “Company”) entered into the Fifth Amendment to the Section 382 Rights Agreement (the “FifthAmendment”), which amends the Section 382 Rights Agreement, dated as of August 14, 2020 (the “Rights Agreement”), by and between the Company and Continental Stock Transfer & Trust Company, as rights agent. Effective as of June 2, 2021, the Company amended the Rights Agreement (the “First Amendment”) to extend the Final Expiration Date (as defined in the Rights Agreement) of the rights issued pursuant to the Rights Agreement from the close of business on August 13, 2021 to the close of business on June 2, 2024. Effective as of May 16, 2024, the Company amended the Rights Agreement (the “Second Amendment”) to extend the Final Expiration Date of the rights issued pursuant to the Rights Agreement from the close of business on June 2, 2024 to the close of business on March 31, 2025. Effective as of March 31, 2025, the Company entered into the Third Amendment (the “ThirdAmendment”) to extend the Final Expiration Date of the rights issued pursuant to the Rights Agreement from the close of business on March 31, 2025 to the close of business on June 30, 2026. On August 13, 2025, the Company entered into the Fourth Amendment, to amend the Final Expiration Date of the rights issued pursuant to the Rights Agreement from the close of business on June 30, 2026 to the close of business on September 30, 2025. On September 30, 2025, the Company entered into the Fifth Amendment to amend the Final Expiration Date of the rights issued pursuant to the Rights Agreement from the close of business on September 30, 2025 to the close of business on December 31, 2025. Except for the adjustment to the Final Expiration Date, the Rights Agreement otherwise remains unmodified.
The Fifth Amendment has been adopted because the Company’s management believes that it is in the best interests of the Company and its stockholders to provide for a Final Expiration Date of December 31, 2025, as established in the Fifth Amendment.
The foregoing description does not purport to be complete and is qualified in its entirety by reference to the complete text of (i) the Rights Agreement, which was filed with the U.S. Securities and Exchange Commission (the “SEC”) as Exhibit 4.1 to the Company’s Registration Statement on Form 8-A filed with the SEC on August 14, 2020, (ii) the First Amendment, which was filed with the SEC as Exhibit 4.1 to the Current Report on Form 8-K filed on June 8, 2021, (iii) the Second Amendment, which was filed with the SEC as Exhibit 4.1 to the Current Report on Form 8-K filed on May 22, 2024, (iv) the Third Amendment, which was filed with the SEC as Exhibit 4.1 to the Current Report on Form 8-K filed on April 1, 2025, (v) the Fourth Amendment, which was filed with the SEC as Exhibit 4.1 to the Quarterly Report on Form 10-Q filed on August 14, 2025, and (vi) the Fifth Amendment, a copy of which is attached as Exhibit 4.1 hereto and incorporated herein by reference. The Rights Agreement, the First Amendment, the Second Amendment, the Third Amendment, the Fourth Amendment, and the Fifth Amendment are incorporated herein by reference.
| Item 3.03 | Material Modification to Rights of Security Holders. |
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The information set forth in Item 1.01 of this Current Report on Form 8-K is incorporated by reference into this Item 3.03.
| Item 9.01 | Financial Statements and Exhibits. |
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(d) Exhibits.
| Exhibit | Description |
|---|---|
| 4.1 | Fifth Amendment to the Section 382 Rights Agreement, dated as of September 30, 2025, by and between Enzon Pharmaceuticals, Inc. and Continental Stock Transfer & Trust Company. |
| 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: September 30, 2025 | ||
| By: | /s/ Richard L. Feinstein | |
| Name: | Richard L. Feinstein | |
| Title: | Chief Executive Officer, Chief Financial Officer and Secretary |
Exhibit 4.1
FIFTH AMENDMENT TO THE
SECTION 382 RIGHTS AGREEMENT
by and between
ENZON PHARMACEUTICALS, INC.
and
CONTINENTAL STOCK TRANSFER & TRUSTCOMPANY,
as Rights Agent
This FIFTH AMENDMENT TOTHE SECTION 382 RIGHTS AGREEMENT (this “Fifth Amendment”) is made and entered into September 30, 2025 and is effective immediately, by and between Enzon Pharmaceuticals, Inc., a Delaware corporation (the “Company”), and Continental Stock Transfer & Trust Company, a New York corporation, as rights agent (the “Rights Agent”).
WHEREAS, the Company and the Rights Agent are parties to that certain Section 382 Rights Agreement, dated as of August 14, 2020 (the “Rights Agreement”), as initially amended on June 4, 2021, further amended on May 16, 2024, further amended on March 31, 2025, and further amended on August 13, 2025 (the “Fourth Amendment”);
WHEREAS, the Rights Agreement, under the terms of the Fourth Amendment, will expire on September 30, 2025;
WHEREAS, the Company may amend the Rights Agreement pursuant to Section 26 thereof; and
WHEREAS, the Board of Directors of the Company has determined that it is in the best interests of the Company and its stockholders to extend the Final Expiration Date to December 31, 2025, in accordance with the terms set forth in this Fifth Amendment.
NOW,THEREFORE, in consideration of the foregoing and other good and valuable consideration, the receipt and sufficiency of which the parties hereby acknowledge, the Company and the Rights Agent agree as follows:
- Amendments.
| (a) | Section 7(a) of the Rights Agreement is hereby amended<br> and restated to read as follows: |
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“Subject to Section 7(e) and Section 27 hereof, the registered holder of any Rights Certificate may exercise the Rights evidenced thereby (except as otherwise provided herein including, without limitation, the restrictions on exercisability set forth in Section 9(c), Section 11(a)(iii) and Section 23(a) hereof) in whole or in part at any time after the Distribution Date upon surrender of the Rights Certificate, with the form of election to purchase and the certificate on the reverse side thereof duly executed, to the Rights Agent at the principal office or offices of the Rights Agent designated for such purpose, together with payment of the aggregate Purchase Price with respect to the total number of one one-thousandth of a share of Preferred Stock (or other securities, cash or other assets, as the case may be) as to which such surrendered Rights are then exercisable, at or prior to the earliest of (i) the Close of Business on December 31, 2025 (the “Final Expiration Date”), (ii) the time at which the Rights are redeemed as provided in Section 23 hereof, (iii) the time at which all of the Rights (other than Rights that have become void pursuant to the provisions of Section 7(e) hereof) are exchanged for Common Stock or other assets or securities as provided in Section 27 hereof, (iv) the Close of Business on the effective date of the repeal of Section 382 of the Code or any successor statute if the Board of Directors determines that this Agreement is no longer necessary or desirable for the preservation of Tax Benefits, or (v) the Close of Business on the first day of a taxable year of the Company to which the Board of Directors determines that no Tax Benefits may be carried forward (the earliest of (i) and (ii) and (iii) and (iv) and (v) being herein referred to as the “Expiration Date”).
| (b) | All references to “September 30, 2025” in Exhibit B<br> (Form of Rights Certificate) and Exhibit C (Summary of Rights to Purchase<br> Series A-1 Junior Participating Preferred Stock) to the Rights Agreement are amended<br> to replace each such reference with “December 31, 2025.” |
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Capitalized Terms. Capitalized terms not defined herein shall have the meanings given such terms in the Rights Agreement.
Descriptive Headings. Descriptive headings of the several Sections of this Fifth Amendment are included for convenience of reference only and shall not control or affect the meaning or construction of any of the provisions hereof.
Governing Law. This Fifth Amendment shall be deemed to be a contract made under the laws of the State of Delaware and for all purposes shall be governed by and construed and enforced in accordance with the laws of such state applicable to contracts to be made and performed entirely within such State.
Counterparts. This Fifth Amendment may be executed in any number of counterparts and each of such counterparts shall for all purposes be deemed to be an original, and all such counterparts shall together constitute but one and the same instrument. A signature to this Fifth Amendment executed and/or transmitted electronically shall have the same authority, effect and enforceability as an original signature.
Effect of FifthAmendment. Except as expressly modified by this Fifth Amendment, the Rights Agreement remains in full force and effect and is hereby ratified and confirmed.
[Remainder of page left intentionallyblank]
INWITNESS WHEREOF, the parties hereto have caused this Fifth Amendment to be duly executed as of the date first written above.
| ENZON PHARMACEUTICALS, INC. | |
|---|---|
| By: | /s/ Richard<br> L. Feinstein |
| Name: | Richard L. Feinstein |
| Title: | Chief Executive Officer, Chief Financial Officer and<br> Secretary |
| CONTINENTAL STOCK TRANSFER & TRUST COMPANY | |
| By: | /s/ Henry Farrell |
| Name: | Henry Farrell |
| Title: | Vice President |
[Signature Page to Fifth Amendment toRights Agreement]