Grey Wolf Therapeutics makes £2.5 million in Series A2

OXFORD, UK—Grey Wolf Therapeutics, a drug discovery biotechnology company focused on developing first-in-class therapies for immuno-oncology, announced today that it has completed a £2.5 million ($3.3 million) Series A2 financing round with international healthcare investors Andera Partners and Canaan.

The new funding, which comes from existing investors, will allow the company to accelerate development of therapies targeting endoplasmic reticulum aminopeptidase 2 (ERAP2), following many positive signals of its potential. Funds will also be used to continue to drive the lead endoplasmic reticulum aminopeptidase 1 (ERAP1) modulator program.

“We have continued to generate data showing that modulation of both ERAP pathways drives change to the cancer-related antigen repertoire,” said Tom McCarthy, executive chairman and co-founder of Grey Wolf Therapeutics. “Data clearly demonstrates that modulation of ERAP2 drives an altogether different change to the antigen repertoire, when compared with ERAP1 modulation, due to ERAP2’s clearly differentiated peptide substrate specificities. With this investment and the prior knowledge base within Grey Wolf we will be able to accelerate the ERAP2 program quickly through optimization, building on our leading position in ERAP disease-related biology.”

Both of Grey Wolf’s novel ERAP approaches are aimed at directly altering tumor cells, illuminating them for attack and destruction by the immune system. The goal is to exploit this increased tumor visibility in monotherapy, and to extend the therapeutic benefit of already-approved immunotherapies to many more cancers. Grey Wolf is developing small molecule modulators of ERAP1 and ERAP2, two key proteins in the antigen presentation pathway, to change the antigen repertoire of tumors and thereby increase the number and range of cancer-related antigens — including neoantigens — present on tumor cells and available to engage an immune response.

“Grey Wolf have already provided compelling insight into the potential of ERAP1 modulation. This timely investment further underlines our excitement in these approaches. Grey Wolf are fast becoming true experts in modulation of ERAP biology for treatment of cancer,” noted Raphaël Wisniewski, partner at Andera Partners.

Grey Wolf is expanding efforts around ERAP2 because clinical data continues to demonstrate that tumors which are more visible to the immune system show improved responses to checkpoint inhibitors. One such example is the recent November 2019 paper published in Nature Medicine by the Chan group at Memorial Sloan Kettering Cancer Center. The results are consistent across patients which have either a higher tumor mutational burden, heterozygosity of the Class I HLA locus, or greater structural / sequence divergence at the Class I HLA locus.

The company has also developed insight into the targeting of the ERAP enzymes through the lead program ERAP1, and validated the role for ERAP inhibition in modulating the cancer-related antigen repertoire. These in-house data provide compelling evidence that the therapies could have a real impact in the treatment of oncology.

“Canaan continues to be excited by the potential of targeting the ERAP pathway and are impressed with the progress the team has made in such a short space of time since closing Series A,” added Brent Ahrens, general partner at Canaan. “The additional A2 investment enables the Company to push forward ERAP2 whilst maintaining the momentum on the lead ERAP1 program.”