CERo Therapeutics Progresses Phase 1 CER-1236 AML Trial with Dosing of Third Patient in Initial Dose Cohort

Third patient in the first cohort is now advancing through protocol-defined evaluations as Company anticipates additional results from second dosing of second patient in the cohort

SOUTH SAN FRANCISCO, Calif, Sept. 22, 2025 (GLOBE NEWSWIRE) -- CERo Therapeutics Holdings, Inc. (NASDAQ:CERO) ("CERo" or the "Company"), an innovative cellular immunotherapy company, today announced that it has dosed the third patient in the starting dose cohort of its Phase 1 clinical trial evaluating CER-1236 in acute myeloid leukemia (AML). Per protocol, three patients are planned at this lowest dose level, and enrollment of the third subject may complete the initial cohort pending the outcome of protocol-defined safety assessments, including the dose-limiting toxicity (DLT) evaluation period.

Stephen Strickland, Jr., M.D., MSCI, Director of Leukemia Research at Sarah Cannon Research Institute (SCRI) and lead investigator at the site where the third patient was dosed, commented, "Advancing to the third and final planned patient at the starting dose level represents an important step in this first-in-human evaluation of CER-1236 as well as our understanding of the critical safety and pharmacokinetic information gained at this initial cohort. We look forward to providing this opportunity to additional patients as we continue to define the biological activity and potential clinical impact of this novel autologous T-cell therapy."

The ongoing first-in-human, multi-center, open-label, Phase 1/1b study is designed to evaluate the safety, tolerability, and preliminary activity of CER-1236 in patients with AML that is relapsed/refractory, in remission with measurable residual disease, or newly diagnosed with TP53-mutated MDS/AML or AML. The two-part trial begins with dose escalation to establish a recommended Phase 2 dose, followed by an expansion phase to further characterize safety and exploratory efficacy. Primary outcome measures include incidence of adverse events (AEs), serious adverse events (SAEs), dose-limiting toxicities (DLTs), and preliminary anti-leukemic activity as measured by overall response rate (ORR), complete response (CR), composite complete response (cCR), and measurable residual disease (MRD). Secondary outcome measures include pharmacokinetics (PK).

Chris Ehrlich, CERo Therapeutics Chief Executive Officer, stated, "Dosing the third and final planned patient in the starting dose cohort represents an important milestone for CERo. At this lowest dose level, we have observed pharmacokinetic data showing cell expansion, and with IRB approval and customary FDA submission, the protocol has been modified to increase dosing potential within each cohort by allowing for a second infusion in the same subject. While early, these changes are expected to provide valuable information as we prepare to move to higher doses, which are designed to more fully explore the potential for enhanced biological activity. We remain encouraged by the progress of the study and deeply grateful to the patients, investigators, and our team who have made this advancement possible."

About CERo Therapeutics Holdings, Inc.

CERo is an innovative immunotherapy company advancing the development of next generation engineered T cell therapeutics for the treatment of cancer. Its proprietary approach to T cell engineering, which enables it to integrate certain desirable characteristics of both innate and adaptive immunity into a single therapeutic construct, is designed to engage the body's full immune repertoire to achieve optimized cancer therapy. This novel cellular immunotherapy platform is expected to redirect patient-derived T cells to eliminate tumors by building in engulfment pathways that employ phagocytic mechanisms to destroy cancer cells, creating what CERo refers to as Chimeric Engulfment Receptor T cells ("CER-T"). CERo believes the differentiated activity of CER-T cells may allow broader therapeutic application than currently approved chimeric antigen receptor ("CAR-T") cell therapy, as the use of CER-T may potentially span both hematological malignancies and solid tumors. CERo has commenced clinical trials for its lead product candidate CER-1236 for hematological malignancies.

Forward-Looking Statements

This communication contains statements that are forward-looking and as such are not historical facts. This includes, without limitation, statements regarding the financial position, business strategy and the plans and objectives of management for future operations of CERo. These statements constitute projections, forecasts and forward-looking statements, and are not guarantees of performance. Such statements can be identified by the fact that they do not relate strictly to historical or current facts. When used in this communication, words such as "anticipate," "believe," "continue," "could," "estimate," "expect," "intend," "may," "might," "plan," "possible," "potential," "predict," "project," "should," "strive," "would" and similar expressions may identify forward-looking statements, but the absence of these words does not mean that a statement is not forward-looking. When CERo discusses its strategies or plans, it is making projections, forecasts or forward-looking statements. Such statements are based on the beliefs of, as well as assumptions made by and information currently available to, CERo's management.

Actual results could differ from those implied by the forward-looking statements in this communication. Certain risks that could cause actual results to differ are set forth in CERo's filings with the Securities and Exchange Commission, including its most recent Annual Report on Form 10-K and subsequent Quarterly Reports on Form 10-Q, and the documents incorporated by reference therein. The risks described in CERo's filings with the Securities and Exchange Commission are not exhaustive. New risk factors emerge from time to time, and it is not possible to predict all such risk factors, nor can CERo assess the impact of all such risk factors on its business, or the extent to which any factor or combination of factors may cause actual results to differ materially from those contained in any forward-looking statements. Forward-looking statements are not guarantees of performance. You should not put undue reliance on these statements, which speak only as of the date hereof. All forward-looking statements made by CERo or persons acting on its behalf are expressly qualified in their entirety by the foregoing cautionary statements. CERo undertakes no obligation to update or revise publicly any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.

Contact:

Chris Ehrlich

Chief Executive Officer

[email protected]

Investors:

Core IR

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