Roche has agreed to pay Nurix Therapeutics $700 million in cash upfront to co-develop and co-commercialize bexobrutideg (NX-5948), the South San Francisco biotech’s lead BTK degrader, in a deal the companies say could reach $2.3 billion if development, regulatory and sales milestones are met.

The structure is closer to a partnership than a licensing handoff. In the United States, the two firms will share development costs 40/60 — Nurix 40%, Roche 60% — and split US profits and losses equally across all indications. Outside the US, Roche takes commercialization, paying Nurix royalties the companies describe only as “ranging from the low- to high-teens.” Both figures come from Nurix’s own announcement and are corroborated by Roche’s release; The Vital Record could not independently access Nurix’s Form 8-K to confirm the milestone breakdown.

A degrader, not a blocker

Bexobrutideg is an oral, brain-penetrant small molecule that the companies say eliminates the BTK protein from cells rather than merely blocking its kinase activity — the mechanism that distinguishes degraders from established BTK inhibitors. That premise is now being tested where it matters most: directly against a marketed competitor.

ClinicalTrials.gov lists a Phase 3 trial (NCT07516093) of bexobrutideg versus pirtobrutinib in relapsed or refractory chronic lymphocytic leukemia and small lymphocytic lymphoma, with planned enrollment of 620 patients. It is marked not yet recruiting, with a June 2026 start. A single-arm Phase 2 (NCT07221500, 100 patients) in CLL/SLL previously treated with both a BTK inhibitor and a BCL-2 inhibitor is recruiting, and the foundational Phase 1 dose-escalation study (NCT05131022) lists 572 participants.

The companies frame ambitions beyond oncology — chronic spontaneous urticaria and multiple sclerosis — but the registry’s pivotal program is, for now, the CLL head-to-head.

For Roche, the deal extends a deliberate push into targeted protein degradation. For Nurix, the $700 million is by far its largest single payment to date and, per chief executive Arthur Sands, “a major step” toward becoming a fully integrated company. No efficacy or safety figures are reported here: bexobrutideg remains investigational, and no readouts from the pivotal trials have been published. This is not investment advice.