Interim Results from Ongoing Phase 1/2 Clinical Trial of Lead Immuno-Oncology Candidate to be Reported in Poster Presentation


OXFORD, UK – May 29, 2024 – Grey Wolf Therapeutics, a clinical-stage biotechnology company leveraging first-of-its-kind antigen modulation therapies to address the source of immune dysfunction in oncology and autoimmunity, today announced that the first clinical data for the company’s lead immuno-oncology candidate, GRWD5769, will be presented at the 2024 American Society of Clinical Oncology (ASCO) Annual Meeting. The presented findings will consist of initial data from the company’s ongoing Phase 1/2 clinical trial of the first-in-class ERAP1 inhibitor in a range of solid tumour types. The 2024 ASCO Annual Meeting is being held May 31 – June 4, 2024, in Chicago, IL.


Details of the company’s presentation at the 2024 ASCO Annual Meeting are as follows:


 Abstract Number: 2589

  • Title: EMITT-1: Proof-of-mechanism immunopeptidome (ImPD) effects at target PK exposure, in a Phase 1 study of GRWD5769 (a first-in-class inhibitor of Endoplasmic Reticulum Aminopeptidase 1 [ERAP1]) in patients with solid malignancies
  • Presenting Author: Thomas Lillie, M.D., Ph.D., Chief Medical Officer of Grey Wolf Therapeutics
  • Poster Session: Development Therapeutics – Immunotherapy
  • Date/Time: Saturday, June 1, 2024, 9:00 a.m. Central Time
  • Location: Poster Hall – Hall A


Grey Wolf has developed and is advancing a unique immune-oncology therapeutic strategy utilizing a proprietary antigen modulation strategy to reveal novel and potent cancer antigens on the surface of tumour cells. This is achieved through oral delivery of a targeted inhibitor of the endoplasmic reticulum aminopeptidases (ERAP1 or ERAP2), key proteins in the antigen presentation pathway. The targeted inhibition of ERAP is designed to elicit a de novo T cell response against tumours and to avoid T-cell exhaustion, thereby overcoming two key resistance mechanisms to current immuno-oncology therapy. The company is conducting an ongoing adaptive Phase 1/2 clinical trial of GRWD5769, which is evaluating the safety, tolerability, and efficacy of GRWD5769, including a planned combination with the PD-1 inhibitor Libtayo® (cemiplimab), in a range of solid tumour types.

The company recently reported that it is expanding the scope of the Phase 1/2 trial, allowing for the enrolment of patients with additional tumour types. Additionally, the company has also recently initiated dosing in the study’s first combination treatment cohort.


About Grey Wolf Therapeutics

Grey Wolf Therapeutics is a clinical-stage, UK- and Australian-based drug discovery and development biotechnology company spearheading a new therapeutic approach based on a first-of-its-kind antigen modulation platform. The company’s innovative technology is centered on inhibiting the endoplasmic reticulum aminopeptidases (ERAP1 or ERAP2), which play a key role in the antigen presentation pathway, allowing therapeutic approaches to address the source of immune dysfunction in oncology and autoimmunity. The company’s lead clinical development candidate, GRWD5769, is a potent and selective oral ERAP1 inhibitor that has shown the potential to elicit a powerful and differentiated immune response against tumours. A second ERAP1 inhibitor, GRWD0715, is advancing through preclinical development as a potential treatment for autoimmune disease. The company is also leveraging its leadership in neoantigen creation with an ERAP2 drug discovery program and by therapeutically targeting novel ERAP1 inhibitor generated cancer antigens with MHC Class I directed therapies, such as soluble T cell receptor (TCR) and TCR mimic bispecifics.

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Grey Wolf Therapeutics

Peter Joyce

Chief Executive Officer

+44 (0) 01235 644 970


Vida Strategic Partners (on behalf of Grey Wolf Therapeutics)

Tim Brons (Media)