Grey Wolf Therapeutics Announces Clinical Supply Agreement with Regeneron for Trial Evaluating GRWD5769 in Combination with Libtayo® (cemiplimab)

Combination of First-in-Class ERAP1 Inhibitor and Anti-PD-1 Monoclonal Antibody to be Studied in Patients with a Range of Advanced Solid Tumours 

Oxford, UK and Melbourne, Australia – Nov 16, 2022

Grey Wolf Therapeutics, a biotechnology company focused on generating entirely novel anti-tumour immune responses through targeted cancer neoantigen creation, today announced it has entered into a clinical supply agreement with Regeneron for their PD-1 inhibitor Libtayo® (cemiplimab). The agreement relates to Grey Wolf’s planned Phase 1/2 clinical trial evaluating the safety, tolerability and efficacy of their lead development candidate GRWD5769 (an investigational first-in-class ERAP1 inhibitor), including in combination with Libtayo®, in a range of solid tumour types. The study is expected to begin in the first half of 2023.

In both the GRWD5769 monotherapy and GRWD5769/Libtayo® combination modules of the trial, a particular focus will be on patients with virally associated solid tumours, such as head and neck squamous cell carcinoma, cervical cancer, and hepatocellular carcinoma as Grey Wolf’s analysis of patient data suggests these could be particularly sensitive to GRWD5769.

“GRWD5769 is a first-in-class ERAP1 inhibitor, designed to upregulate the generation of novel neoantigens, and mobilise an entirely novel T cell response against tumours, and in so doing overcome the challenges of T cell exhaustion. Based on this unique mechanism, we believe this compound holds great promise as a monotherapy, and we’re excited to evaluate our approach in the clinic where there is a particularly strong rationale for observing striking effects in patients with virally associated cancers.” said Peter Joyce, Ph.D., chief executive officer of Grey Wolf Therapeutics. “At the same time, we believe that this innovative approach to attacking cancer also has great potential to synergistically improve outcomes when used in rational combination with other anti-cancer agents, particularly immune checkpoint inhibitors. As such, we are looking forward to the opportunity to assess GRWD5769 in combination with Regeneron’s Libtayo®. Their continued investment in immuno-oncology innovation is clearly aligned with our first in class approach to cancer immunotherapy and we are delighted to be working with them as we progress into the clinic”.

About Grey Wolf Therapeutics

Grey Wolf Therapeutics is a UK and Australian based drug discovery and development biotechnology company spearheading a new therapeutic approach in immuno-oncology. The company’s first-of-its-kind immuno-oncology approach is centered on inhibiting the endoplasmic reticulum aminopeptidases (ERAP1 or ERAP2) which play a key role in the antigen presentation pathway. Inhibiting ERAP1 or ERAP2 generates novel neoantigens and upregulates certain neoantigens, resulting in the mobilisation of an entirely novel T cell response against the tumour that bypasses the challenge faced by current treatment options when once anti-tumourigenic T cells become irreversibly exhausted and hence ineffective. Based on this approach, the company is developing a portfolio of first-in-class small molecules that inhibit ERAP1 or ERAP2. The company’s lead development candidate, GRWD5769, is a potent and selective ERAP1 inhibitor intended to elicit a powerful and differentiated immune response against the tumour and it is expected to enter the clinic in the first half of 2023 subject to ethics and regulatory approval. A second program, focused on ERAP2 inhibition, is advancing through the discovery process.


Grey Wolf Therapeutics
Peter Joyce
Chief Executive Officer
+44 (0) 01865 292 038

Vida Strategic Partners (on behalf of Grey Wolf Therapeutics)
Tim Brons (Media)