Hemogenyx Pharmaceuticals : CDX Antibody Update

1 April 2021

Hemogenyx Pharmaceuticals plc

("Hemogenyx Pharmaceuticals" or the "Company")

CDX Antibody Update

Hemogenyx Pharmaceuticals plc (LSE: HEMO), the biopharmaceutical group developing new therapies and treatments for blood diseases, is pleased to issue an update on negotiations regarding the future development of its leading product candidate CDX bispecific antibody ("CDX") for the treatment of acute myeloid leukemia ("AML").

On 13 January 2021, the Company announcedthe completion of development of CDX with a global pharmaceutical company ("GlobalCo"). With the development phase of the agreement completed, GlobalCo or the Company may exercise an option to license the other party's intellectual property necessary to exploit the CDX antibody on an exclusive worldwide basis.

The Company is pleased to announce that negotiations have commenced with GlobalCo regarding the form of licensing and further development of CDX toward clinical trials. The results of these negotiations and the outline of the path toward the further development of CDX will be announced upon their completion.

At the same time, the Company is progressing in the development of its leading product candidate Chimeric Antigen Receptor ("CAR") T-cells("HEMO-CAR-T"). As announced on 3 March 2021, the Company has engaged a highly experienced consultant in the field of manufacturing and quality control operations and has initiated the process of engaging contract manufacturing organizations ("CMOs") for product development and manufacturing to support Phase I clinical trials of HEMO- CAR-T. Discussions and negotiations with CMOs continue and the Directors are confident that the Company is poised to move ahead toward clinical trials with an outstanding team, including the University of Pennsylvania, with which the Company has entered into a Master Translational Research Services Agreement, the goal of which is to advance HEMO-CAR-T toward clinical trials.

Hemogenyx Pharmaceuticals plc is registered in England and Wales as company number 08401609

Registered office: 5 Fleet Place, London, EC4M 7RD

Dr Vladislav Sandler, CEO & Co-Founder of Hemogenyx Pharmaceuticals, commented: "We are pleased with the continued interest of GlobalCo in facilitating the advancement of the CDX antibody toward the clinic, having concluded the highly successful development phase of this product candidate. We are also excited about the progress being made in moving HEMO-CAR-Ttoward clinical trials. Having two lead product candidates that have resulted in collaborations with such esteemed organizations and both moving toward clinical trials is testament to the Company's exceptional team of scientists and our dedication to cutting edge science."

About AML

AML, the most common type of acute leukemia in adults, has poor survival rates (a five-year survival rate of less than 30% in adults) and is currently treated using chemotherapy, rather than the potentially more benign and effective form of therapy being developed by Hemogenyx Pharmaceuticals. The successful development of the new therapy for AML would have a major impact on treatment and survival rates for the disease.

About CAR-T Therapy

CAR-T therapy is a treatment in which a patient's own T-cells, a type of immune cell, are modified to recognize and kill the patient's cancer cells. The procedure involves: isolating T-cells from the patient; modifying the isolated T-cells in a laboratory using a CAR gene construct (which allows the cells to recognize the patient's cancer); amplifying (growing to large numbers) the newly modified cells; and re-introducing the cells back into the patient.

Market Abuse Regulation (MAR) Disclosure

Certain information contained in this announcement would have been deemed inside information for the purposes of Article 7 of Regulation No 596/2014 until the release of this announcement.

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Enquiries:

Hemogenyx Pharmaceuticals plc	https://hemogenyx.com
Dr Vladislav Sandler, Chief Executive Officer & Co-Founder	[e-mail]
Peter Redmond, Director	[e-mail]
SP Angel Corporate Finance LLP	Tel: [phone]
Matthew Johnson, Vadim Alexandre, Adam Cowl
Peterhouse Capital Limited	Tel: [phone]
Lucy Williams, Duncan Vasey, Charles Goodfellow

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 pre-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.

For more than 50 years, bone marrow transplantation has been used to save the lives of patients suffering from blood diseases. The risks of toxicity and death that are associated with bone marrow transplantation, however, have meant that the procedure is restricted to use only as a last resort. The Company's technology has the potential to enable many more patients suffering from devastating blood diseases such as leukemia and lymphoma, as well as severe autoimmune diseases such as multiple sclerosis, aplastic anemia and systemic lupus erythematosus (Lupus), to benefit from bone marrow transplantation.

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