Partnered with Gilead and Sanofi, protein degradation specialist Nurix bags $120M to chart its own clinical path
The race to steer the first protein degradation drugs to the clinic is on.
On the same day that Cambridge, MA-based Kymera Therapeutics unveiled a $102 million round to enter into development phase, Nurix said it has raised $120 million to do the same out of San Francisco’s Mission Bay.
Foresite Capital led the round. Redmile Group, a co-leader in Kymera’s Series C, participated alongside Bain Capital Life Sciences, Boxer Capital (Tavistock Group), EcoR1 Capital, Wellington Management Company and an undisclosed investor, as well as founding investors The Column Group and Third Rock Ventures.
Investing out of its $668 million Fund IV, Foresite is interested in any new modalities for drug discovery. Having followed Nurix since at least 2017, staying in touch with CEO Arthur Sands and his team through the years, partner Michael Rome said now is the perfect time to get involved.
“What’s really unique about the company is they spent several years developing their platform technology, whether that’s their DNA encoded libraries, or their specific CTM molecules,” he said, referring to its chimeric targeting molecules harnessing E3 ligases.
That deep dive into the biology of E3 ligases — the ubiquitin tag that tells the cell’s garbage disposal system that a certain protein is up for degradation — has allowed Nurix to go beyond simply reappropriating the natural machinery. There are certain E3 ligases, it turned out, that degrade proteins necessary for the immune system to mount an attack on cancer. Blocking them can unleash the body’s full defense.
“They’re very complex protein structures,” Nurix CFO Hans van Houte told Endpoints News. “It turns out that there are probably over 600 E3 ligases in the human genome, and they all have certain roles to play in terms of regulating protein levels themselves.”
According to him, it gives them an edge over rivals at Kymera, C4 and even Arvinas (which is in a Phase I trial for prostate cancer).
Van Houte made a clear distinction between deal money — $100 million in upfront total and $4.5 billion in potential milestones — and the new financing. While the former is helping beef up its research organization, the latter is strictly reserved for bringing the two wholly-owned franchises (with two programs each) into human testing in the next 12 to 18 months.
The first aims to degrade BTK, the kinase target for marketed drugs like J&J/AbbVie’s Imbruvica, AstraZeneca’s Calquence and BeiGene’s Brukinsa. But tumors can develop a resistance to these therapies. Nurix hopes that by following a different mechanism of action, its CTM can bypass the resistance mutations and induce deeper and more durable response.
Another has to do with a type of E3 ligase dubbed CBL-B, which is found to negatively regulate T cell activation. Inhibiting it, van Houte said, triggers the secretion of the powerful cytokine IL-2.
Nurix recently recruited biotech vet Jean Chang as VP of program management and asset strategy as part of a plan to build out the development team on top of its current 95-strong workforce. It expects to file an IND by the end of the year.