Canaan leaps into UK biotech by co-leading $14M Series A for immuno-oncology upstart Grey Wolf
Checkpoint inhibitors have done wonders for immuno-oncology, but the potent class of drugs doesn’t work across all cancers. To remedy this, UK-based biotech upstart Grey Wolf Therapeutics is working on a fresh approach that does not directly target the immune system, but instead alters tumor cells by illuminating and priming them for immune system annihilation — a strategy that could work in conjunction with existing immunotherapies.
Andera Partners and Canaan have shown their faith in the concept by leading an approximately $14 million series A round for the company.

Founded by former Vertex executive Peter Joyce and ex-chief of Spinifex Pharmaceuticals Tom McCarthy, Grey Wolf is developing small molecule modulators of endoplasmic reticulum aminopeptidases (ERAPs) proteins, an approach designed to shore up the quantity and range of neoantigens presented on tumor cells.
“The enzyme targets we’re going after are ERAP1 and ERAP2 — they work in the antigen presentation pathway and essentially by modulating their activity, we can modulate what is presented on the surface of a cancer cell, so we actually change the neoantigens and modulate their visibility,” Joyce told Endpoints News, adding that preclinical data suggests that a monotherapy approach is feasible, as is a combination with existing PD-1s.
Grey Wolf is working with the University of Oxford, University of Southampton, and has a strategic partnership with Sygnature Discovery, a Nottingham-based provider of drug discovery and preclinical services. Sygnature and McCarthy together put in £420,000 in seed funding for Grey Wolf, Joyce said.
Back in 2015, McCarthy was in charge of Spinifex when it was sold to Swiss drugmaker Novartis $NVS in a $700 million deal after the publication of positive Phase II data on its non-opioid painkiller. Noted VC Canaan was an investor in Spinifex.
Canaan has made its first-ever investment in UK biotech with its Grey Wolf investment, thanks in part to McCarthy’s relationship with the firm, and due to the scientific potential of the ERAP approach, Joyce said. “(The) fact that we’re doing something very novel really piqued their interest.”
According to Joyce, outside of academic institutions, there aren’t any other commercial entities looking at modulating ERAP proteins for immuno-oncology to his knowledge and Grey Wolf is “aiming to be first-in-class.”
The company, which has a core team of 6, is currently in the drug discovery phase, and this round of funding will be used to take the company to pre-IND enabling studies in the next 2-3 years. “We either exit at that point — which we would be open to — or get a partner. Or we might do a Series B and take it to Phase I/II. I think beyond…the complexity of immuno-oncology clinical development really then does need one of the bigger partners,” Joyce said.
“I’m a fly fisherman by background and Grey Wolf is a type of mayfly and it’s a bit of lucky fly for me…so I’m hoping it will be a sort of a good luck omen.”