as Exhibit 99.1 hereto and is incorporated herein by reference. The information contained in this Current Report on Form 8-K, including the Press Release, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information contained herein and in the Press Release shall not be incorporated by reference into any fi…

The filing details an amendment to the equity incentive plan, not a management change.

as Exhibit 99.1 hereto and is incorporated herein by reference. The information contained in this Current Report on Form 8-K, including the Press Release, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information contained herein and in the Press Release shall not be incorporated by reference into any fi…

as Exhibit 99.1 hereto and is incorporated herein by reference. The information contained in this Current Report on Form 8-K, including the Press Release, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information contained herein and in the Press Release shall not be incorporated by reference into any fi…

Other Events. On January 9, 2026, Delcath disclosed in the Corporate Presentation that as of December 31, 2025, (i) it had a total of 25 active sites utilizing HEPZATO KIT and (ii) there were approximately 34.7 million shares of its common stock issued and outstanding. In addition, Delcath disclosed in the Corporate Presentation that the Company achieved positive operating cash for the quarter ended December 31, 2025. On January 9, 2026, Delcath also announced the following preliminary unaudi…

as Exhibit 99.1 and Exhibit 99.2, respectively, and each such exhibit is incorporated herein by reference. The information contained in this Item 2.02, including Exhibits 99.1, and 99.2 shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section nor shall it be incorporated by reference into any other filing by Delcath with the U.S. Securities and Exchange Commission whether made before or a…

Other Events. On November 19, 2025, the board of directors of Delcath Systems, Inc., a Delaware corporation (the “Company”) authorized a share repurchase program under which the Company may repurchase up to $25 million of its outstanding shares of common stock from time to time, subject to market conditions. SIGNATURE Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereun…

as Exhibit 99.1 hereto and is incorporated herein by reference. The information contained in this Current Report on Form 8-K, including the Press Release, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information contained herein and in the Press Release shall not be incorporated by reference into any fi…

Other Events. CHOPIN Trial On October 18, 2025, Delcath issued a press release announcing the results of the CHOPIN Trial. A copy of the press release is furnished as Exhibit 99.2. The CHOPIN Trial was designed to compare the safety, tolerability and efficacy of Delcath’s CHEMOSAT ® Hepatic Delivery System (“HDS”) with melphalan for percutaneous hepatic perfusion (“PHP”) when used alone versus when combined with the systemic immune checkpoint inhibitors (“ICI”) ipilimumab and nivolumab. The C…

as Exhibit 99.1 hereto and is incorporated herein by reference. The information contained in this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (“Exchange Act”), or otherwise subject to the liabilities of that section nor shall it be incorporated by reference into any other filing by Delcath with the U.S. Securities and Exchange Commission (the “Commission”) whether made before or after the date her…

as Exhibit 99.1 hereto and is incorporated herein by reference. The information contained in this Current Report on Form 8-K, including the Press Release, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information contained herein and in the Press Release shall not be incorporated by reference into any fi…

Other Events On May 22, 2025, Delcath announced that it plans to enter into a National Medicaid Drug Rebate Agreement (the “NDRA”) with the Centers for Medicare & Medicaid Services and that it expects the NDRA to take effect at the beginning of the third quarter of 2025. Forward-Looking Statements The Private Securities Litigation Reform Act of 1995 provides a safe harbor for forward-looking statements made by Delcath or on its behalf. This Form 8-K contains forward-looking statements, which…

The filing is about an equity plan amendment, not a management change.

as Exhibit 99.1 hereto and is incorporated herein by reference. The information contained in this Current Report on Form 8-K, including the Press Release, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information contained herein and in the Press Release shall not be incorporated by reference into any fi…

Changes in Registrant’s Certifying Accountant. On March 18, 2025, Delcath Systems, Inc. (the “Company”) was notified by Marcum LLP (“Marcum”) that Marcum resigned as the Company’s independent registered accounting firm. On November 1, 2024, CBIZ CPAs P.C. (“CBIZ CPAs”) acquired the attest business of Marcum. On March 18, 2025, following the approval of the Audit Committee of the Company’s Board of Directors, CBIZ CPAs was engaged, effective immediately, as the Company’s independent registered…

as Exhibit 99.1 hereto and is incorporated herein by reference. The information contained in this Current Report on Form 8-K, including the Press Release, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information contained herein and in the Press Release shall not be incorporated by reference into any fi…

as Exhibit 99.1 hereto and is incorporated herein by reference. The information contained in this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section nor shall it be incorporated by reference into any other filing by Delcath with the U.S. Securities and Exchange Commission whether made before or after the date hereof, regardless of any general incor…

as Exhibit 99.1 hereto and is incorporated herein by reference. The information contained in this Current Report on Form 8-K, including the Press Release, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information contained herein and in the Press Release shall not be incorporated by reference into any fi…

as Exhibit 99.1 hereto and is incorporated herein by reference. The information contained in this Current Report on Form 8-K, including the Press Release, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section nor shall it be incorporated by reference into any other filing by Delcath with the U.S. Securities and Exchange Commission whether made before or after the date hereof, regardles…

as Exhibit 99.1 hereto and is incorporated herein by reference. The information contained in this Current Report on Form 8-K, including the Press Release, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information contained herein and in the Press Release shall not be incorporated by reference into any fi…

Chief Executive Officer — Gerard Michel: The CEO's existing employment agreement was updated, but he continues to serve in the same role.

Notice of Delisting or Failure to Satisfy a Continued Listing Rule or Standard; Transfer of Listing. On July 8, 2024, Delcath Systems, Inc. (the “Company”) received a letter from The Nasdaq Stock Market LLC (“Nasdaq”) informing the Company that it had regained compliance with the audit committee composition requirements as set forth in Nasdaq Listing Rule 5605 for continued listing on The Nasdaq Capital Market. As previously disclosed, on May 29, 2024, the Company was notified by Nasdaq that…

Notice of Delisting or Failure to Satisfy a Continued Listing Rule or Standard; Transfer of Listing. The information in

The filing pertains to an equity incentive plan amendment and does not involve any changes in management or directors.

as Exhibit 99.1 hereto and is incorporated herein by reference. The information contained in this Current Report on Form 8-K, including the Press Release, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information contained herein and in the Press Release shall not be incorporated by reference into any fi…