Results of Operations and Financial Condition. On August 6, 2026, CytoSorbents Corporation issued a press release announcing its financial results for the quarter ended June 30, 2026. A copy of the press release is furnished herewith as Exhibit 99.1.*

Notice of Delisting or Failure to Satisfy a Continued Listing Rule or Standard; Transfer of Listing. On June 29, 2026, CytoSorbents Corporation, a Delaware corporation (the “Company”), received a written notice (“Notice”) from the Listing Qualifications Department of the Nasdaq Stock Market LLC (“Nasdaq”) that the Company was not in compliance with Nasdaq Listing Rule 5550(b)(2) because the Company’s minimum Market Value of Listed Securities was below the minimum of $35 million required for c…

Results of Operations and Financial Condition. On May 13, 2026, CytoSorbents Corporation issued a press release announcing its financial results for the quarter ended March 31, 2026. A copy of the press release is furnished herewith as Exhibit 99.1.*

Notice of Delisting or Failure to Satisfy a Continued Listing Rule or Standard; Transfer of Listing. On April 1, 2026, CytoSorbents Corporation, a Delaware corporation (the “Company”), received a letter (the “Extension Notice”) from the Listing Qualifications Staff (the “Staff”) of The Nasdaq Stock Market LLC (“Nasdaq”) advising that the Company has been granted a 180-day extension, or until September 28, 2026, to regain compliance with the requirement to maintain a minimum bid price of $1.00…

Results of Operations and Financial Condition. On March 25, 2026, CytoSorbents Corporation issued a press release announcing its financial results for the quarter and year ended December 31, 2025. A copy of the press release is furnished herewith as Exhibit 99.1.*

of this Form 8-K shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act, except as expressly set forth by specific reference in such a filing. SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly cause…

Notice of Delisting or Failure to Satisfy a Continued Listing Rule or Standard; Transfer of Listing. On October 2, 2025, CytoSorbents Corporation (the “Company”) received written notice from the Listing Qualifications Department of the Nasdaq Stock Market LLC (“Nasdaq”) that the Company was not in compliance with Nasdaq Listing Rule 5550(a)(2) because the Company’s common stock had fallen below $1.00 per share for 30 consecutive business days (the “Minimum Bid Price Requirement”). The written…

of this Form 8-K shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act, except as expressly set forth by specific reference in such a filing. SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly cause…

of this Form 8-K shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act, except as expressly set forth by specific reference in such a filing. SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly cause…

Non-Reliance on Previously Issued Financial Statements or a Related Audit Report or Completed Interim Review. On March 25, 2025, CytoSorbents Corporation (the “Company”), after consultation with the Audit Committee of the Company's Board of Directors determined that the following previously issued consolidated financial statements should no longer be relied upon, due to misstatements in inventory and stock-based compensation for restricted stock units contained in the consolidated financial s…

Results of Operation and Financial Condition On March 31, 2025, CytoSorbents Corporation issued a press release announcing its financial results for the quarter and year ended December 31, 2024. A copy of the press release is furnished herewith as Exhibit 99.1.*

Results of Operation and Financial Condition On March 21, 2025, CytoSorbents Corporation issued a press release reaffirming certain previously disclosed preliminary financial expectations for the quarter and year ended December 31, 2024, as well as announcing its rescheduled earnings call for the quarter and year ended December 31, 2024, which is now expected to occur on March 31, 2025. A copy of the press release is furnished herewith as Exhibit 99.1.*

Results of Operation and Financial Condition On March 4, 2025, CytoSorbents Corporation issued a press release reaffirming certain previously disclosed preliminary financial expectations for the quarter and year ended December 31, 2024, as well as announcing a delay of its previously announced earnings call, which is now expected to occur on March 25, 2025 due to the passing of the Company’s Vice President and Corporate Controller. A copy of the press release is furnished herewith as Exhibit…

Results of Operation and Financial Condition On January 13, 2025, CytoSorbents Corporation issued a press release announcing the conclusion of its subscription period and preliminary results of its Rights Offering, which commenced on December 9, 2024, including certain preliminary and unaudited financial results and business updates for the quarter and year ended December 31, 2024. A copy of the press release is furnished herewith as Exhibit 99.1.*

of this Form 8-K shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act, except as expressly set forth by specific reference in such a filing. SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly cause…

Other Events. On December 9, 2024, CytoSorbents Corporation (the “Company”) announced a rights offering (the “Rights Offering”). The Rights Offering is being made pursuant to the Company’s Registration Statement on Form S-3 (File No. 333-281062) (the “Registration Statement”), the prospectus forming a part of the Registration Statement and the prospectus supplement relating the Rights Offering (the “Prospectus Supplement”), filed with the SEC on December 9, 2024. Copies of the prospectus and…

of this Form 8-K shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act, except as expressly set forth by specific reference in such a filing. SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly cause…

of this Form 8-K shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act, except as expressly set forth by specific reference in such a filing. SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly cause…

Entry into a Material Definitive Agreement On August 16, 2024, CytoSorbents Corporation (the “Company”) entered into an Amended and Restated Letter Agreement (the “Amended and Restated Agreement”) with ROKK, LLC (“ROKK”), pursuant to which the parties amended and restated that certain Letter Agreement, dated as of August 11, 2003, originally entered into by and between RenalTech International, LLC (the predecessor to the Company) and Guillermina Vega Montiel (the “Original Agreement”). As pre…

Chief Financial Officer — Kathleen P. Bloch: Ms. Kathleen P. Bloch retired from her role as Chief Financial Officer and transitioned into a consulting role, with Peter J. Mariani appointed as the new CFO.

of this Form 8-K shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act, except as expressly set forth by specific reference in such a filing. SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly cause…

Entry into a Material Definitive Agreement On June 28, 2024 (the “ Closing Date ”), CytoSorbents Corporation, a Delaware corporation (the “ Company ”), along with CytoSorbents Medical Inc., a Delaware corporation and wholly owned subsidiary of the Company (“ CytoSorbents Medical ” and, together with the Company, the “ Borrower ”), entered into a Loan and Security Agreement (as amended, supplemented, restated or otherwise modified as of the date hereof and from time to time, the “ Loan and Sec…

Notice of Delisting or Failure to Satisfy a Continued Listing Rule or Standard; Transfer of Listing. On May 20, 2024, CytoSorbents Corporation (the “Company”) received written notice from the Listing Qualifications Department of the Nasdaq Stock Market LLC (“Nasdaq”) that the Company was not in compliance with Nasdaq Listing Rule 5550(a)(2) because the Company’s common stock had fallen below $1.00 per share for 30 consecutive business days (the “Minimum Bid Price Requirement”). The written no…

of this Form 8-K shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act, except as expressly set forth by specific reference in such a filing. SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly cause…

The company implemented a voluntary salary reduction program for its named executive officers as part of cost-cutting measures.