Celgene Cozies up to Nurix With $150M Drug Development Deal

Xconomy San Francisco — 

Celgene has established a reputation over the years for forming creative partnerships with nascent biotechs. Today it’s added another deal to that list, by taking an equity stake in a Bay Area startup called Nurix.

Summit, NJ-based Celgene (NASDAQ: CELG) is paying Nurix $150 million up front and making an unspecified equity investment for an option to license future programs coming from the San Francisco biotech over an unspecified term. During that time, Nurix will use its expertise—homing in on the ubiquitin proteasome system (UPS), which breaks down unwanted proteins and helps cells maintain a healthy stage of protein homeostasis—to find drugs for certain inflammatory and immunological diseases.

Nurix will handle all of the discovery work, and keep the lead on these drugs through the end of Phase 1 clinical trials. After that, Celgene can buy rights to each drug for an option fee and downstream milestone payments that, all together, total $405 million. For certain drugs in the deal, Nurix has the option to split U.S. rights with Celgene—and pay Celgene an option fee, milestone payments, and royalties. If Celgene passes on one of these programs, Nurix will keep full rights to it.

The deal is the first partnership Nurix has struck since it was seeded by Third Rock Ventures and The Column Group with $6 million in 2012. The two followed up with a $25 million Series B in May 2014 to help move Nurix along.

Nurix was formed around the work of UC Berkeley and UCSF professors—John Kuriyan, Michael Rape, and Arthur Weiss—who are experts in the UPS. Ubiquitins attach to proteins and essentially flag them for destruction by the proteasome, the cell’s garbage disposal unit. It’s been a tough area for drug developers to target because of how prevalent it is—the first drug to successfully inhibit the proteasome (pictured above) was bortezomib (Velcade), from Millennium Pharmaceuticals. And even that was, as Alnylam Pharmaceuticals CEO (and former Millennium executive) John Maraganore told me a while back, “a very scary program…as people said back then, it was inconsistent with life [to inhibit the proteasome].” Onyx Pharmaceuticals’s carfilzomib (Kyprolis) was the second FDA approved drug to work in this manner.

Nurix is trying to develop small molecule drugs that can either speed up protein degradation or slow it down. Though it hasn’t said which diseases it’s going after with this approach, its drugs will target E2 conjugation enzymes and E3 ligases, which are thought to control which proteins are tagged with ubiquitin. In a statement today, Nurix noted that mutations in certain genes involved in the UPS are implicated in a number of human cancers and the immune system’s response to tumors.

This isn’t Celgene’s first foray, meanwhile, into the field of protein homeostasis—the ability of cells to properly manufacture or deactivate proteins. It has a long-running deal in place with Watertown, MA-based Forma Therapeutics, for instance, to develop drugs that affect protein homeostasis.

“Consistent with our deep commitment and competitive position in the arena of protein homeostasis, we are excited to initiate this collaboration with the exceptional team that Nurix has assembled. This collaboration extends our approach in the E3 ubiquitin ligase space, and provides a highly complementary effort addressing important targets in oncology and immune-inflammatory diseases,” said Thomas Daniel, Celgene’s president of global research and early development, in a statement.