Business Description

OVERVIEW Enzon Pharmaceuticals, Inc. (together with its subsidiaries, the “Company,” “Enzon,” “we” or “us”) is positioned as a public company acquisition vehicle. We were incorporated on May 11, 1983. Historically, we have received royalty revenues from licensing arrangements with other companies primarily related to sales of certain drug products that utilized Enzon’s proprietary technology. For more than ten years, we have had no clinical operations and limited corporate operations. We previously were a party to a marketing agreement relating to the drug Vicineum, which, if approved, could have potentially generated milestone and royalty payments to us in the future. However, our licensee for this drug was canceled by the counterparty to the marketing agreement and our patent for Vicineum has since expired. Accordingly, we do not believe any future revenue will be earned from this product or that if any such revenue is earned it will be material. Merger Agreement On June 20, 2025, the Company, EPSC Acquisition Corp., a Delaware corporation and a wholly owned subsidiary of ours (“Merger Sub”), and Viskase Companies, Inc. (“Viskase”) entered into an Agreement and Plan of Merger, which was amended on October 24, 2025 (as amended, the “Merger Agreement”). Upon the terms and subject to the satisfaction or waiver of the conditions described in the Merger Agreement, at the effective time of the merger, Merger Sub will be merged with and into Viskase, with Viskase as the surviving entity following the merger as a wholly owned subsidiary of Enzon (the “Merger”). Following consummation of the Merger, it is anticipated that Enzon’s pre-closing stockholders, including holders of Enzon’s Series C Non-Convertible Redeemable Preferred Stock (the “Series C Preferred Stock”), will hold 45% of the outstanding shares of Enzon’s Common Stock following the Merger, and Viskase’s pre-closing stockholders will hold 55% of the outstanding shares of Enzon’s Common Stock following the Merger. If the Merger is completed, Enzon Pharmaceuticals, Inc. will change its name to “Viskase Holdings, Inc.” and its common stock will continue to be quoted on the OTCQB tier of the OTC Markets Group, Inc., although pursuant to the rules of the OTCQB, Enzon is required to re-apply to the OTCQB following such change of control transaction. Support Agreement Icahn Enterprises Holdings L.P., a Delaware limited partnership (“IEH”), and certain of its affiliates (collectively with IEH, the “IEH Parties”) beneficially own approximately 48.6% of the outstanding shares of our Common Stock, as well as approximately 98.2% of the outstanding shares of our Series C Preferred Stock. In connection with the execution of the Merger Agreement, IEH and certain of its affiliates entered into the Support Agreement, which was subsequently amended (as amended, the “Support Agreement”). Pursuant to the terms of the Support Agreement, the IEH Parties agreed to, among other things, (i) deliver or cause the delivery of written consents with respect to all of the issued and outstanding shares of Enzon’s Common Stock held by the IEH Parties to approve the Merger and the amendment to Enzon’s certificate of incorporation, and (ii) exchange all of the shares of Series C Preferred Stock held by the IEH Parties for the Company’s Common Stock prior to the consummation of the Merger. Consent Solicitation As required by the Merger Agreement, on January 30, 2026, Enzon commenced a consent solicitation (the “Consent Solicitation”) for its stockholders to provide written consents relating to: (i) an amendment to the Company’s Amended and Restated Certificate of Incorporation (the “Enzon Charter,” and such amendment, the “Enzon Charter Amendment”) to effect the consolidation of the issued and outstanding shares of the Enzon’s Common Stock at a ratio of 1-for-100 (the “Reverse Stock Split” and, such proposal, the “Reverse Stock Split Proposal”); and (ii) the adoption of the Merger Agreement (the “Merger Proposal”) as more fully described in the Prospectus/Consent Solicitation/Offer to Exchange filed by Enzon with the SEC on January 30, 2026. 4 Table of Contents On February 11, 2026, Enzon received written consents from holders of its Common Stock that were sufficient to approve the Reverse Stock Split Proposal and the Merger Proposal. As of the record date for the written consents, there were 74,214,603 shares of Enzon’s Common Stock outstanding and entitled to vote.…