Hemogenyx Pharmaceuticals PLC Announces First Patient Safety

THIS ANNOUNCEMENT CONTAINS INSIDE INFORMATION FOR THE PURPOSES OF ARTICLE 7 OF REGULATION 2014/596/EU WHICH IS PART OF DOMESTIC UK LAW PURSUANT TO THE MARKET ABUSE (AMENDMENT) (EU EXIT) REGULATIIONS (SI 2019/310) ("UK MAR"). UPON THE PUBLICATION OF THIS ANNOUNCEMENT, THIS INSIDE INFORMATION (AS DEFINED IN UK MAR) IS NOW CONSIDERED TO BE IN THE PUBLIC DOMAIN.

24 March 2025

Hemogenyx Pharmaceuticals plc

("Hemogenyx Pharmaceuticals" or the "Company")

First Patient Treated with HG-CT-1 CAR-T Therapy Passes Initial Safety Tests

LONDON, UNITED KINGDOM / ACCESS Newswire / March 24, 2025 / Hemogenyx Pharmaceuticals plc is pleased to announce that the first patient has been successfully treated as part of the Company's Phase I clinical trial of HG-CT-1, the Company's proprietary CAR-T cell therapy for relapsed or refractory acute myeloid leukemia (R/R AML) in adults. The treatment was well tolerated, with no adverse effects observed, thereby passing the initial safety assessment.

Early signs of efficacy are encouraging. The patient will continue to be monitored in accordance with the FDA-approved clinical protocol to evaluate whether the secondary endpoints of the trial are achieved.

Manufacturing of HG-CT-1 is currently underway for the treatment of a second patient.

This Phase I clinical trial is a dose-escalation study designed to evaluate the safety profile of HG-CT-1 in adult patients with R/R AML. In addition to safety, key secondary objectives of the trial include:

• Assessing the efficacy of HG-CT-1 based on AML-specific response criteria

• Evaluating overall survival

• Measuring progression-free survival

• Determining duration of response in patients demonstrating clinical benefit

Data related to these secondary endpoints, including efficacy, durability, and overall clinical outcomes, will be collected over time through continued follow-up of the treated patient. These secondary endpoints are critical for assessing the potential clinical impact of HG-CT-1 in a patient population with limited remaining treatment options.

Further updates on the clinical trial will be provided in due course.

Dr Vladislav Sandler, CEO & Co-Founder of Hemogenyx Pharmaceuticals, commented:
"The successful treatment of the first patient with HG-CT-1 marks a major milestone not only for Hemogenyx Pharmaceuticals but also for patients battling relapsed or refractory AML. We are encouraged by the favorable safety profile observed so far and the early signs of efficacy. This outcome strengthens our confidence in the potential of HG-CT-1 to address one of the most challenging and deadly forms of leukemia. We remain committed to advancing this therapy through clinical development with the goal of delivering a transformative treatment to patients in desperate needwhile creating long-term value for our shareholders."

Market Abuse Regulation (MAR) Disclosure
Certain information contained in this announcement would have been inside information for the purposes of Article 7 of Regulation No 596/2014 (as it forms part of UK domestic law by virtue of the European Union (Withdrawal) Act 2018) until the release of this announcement.

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About Hemogenyx Pharmaceuticals plc
Hemogenyx Pharmaceuticals is a publicly traded company (LSE: HEMO) headquartered in London, with its US operating subsidiaries, Hemogenyx Pharmaceuticals LLC and Immugenyx LLC, located in New York City at its state-of-the-art research facility.

The Company is a clinical-stage biopharmaceutical group developing new medicines and treatments to treat blood and autoimmune disease and to bring the curative power of bone marrow transplantation to a greater number of patients suffering from otherwise incurable life-threatening diseases. Hemogenyx Pharmaceuticals is developing several distinct and complementary product candidates, as well as a platform technology that it uses as an engine for novel product development.

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SOURCE: Hemogenyx Pharmaceuticals PLC