Nurix and Sanofi End Development of STAT6 Degrader

Brisbane, California, USA, November 3, 2026

Sanofi Discontinues Phase 1 Development of SAR448272

SAR448272, also identified as NX-3911, is an investigational oral small-molecule degrader designed to target signal transducer and activator of transcription 6 (STAT6), a protein involved in immune system signaling. STAT6 plays an important role in pathways associated with type 2 inflammation and immune responses. Its activity is linked to signaling mediated by interleukin-4 and interleukin-13, which are involved in several inflammatory and allergic conditions. The candidate was developed through Nurix’s targeted protein degradation research capabilities and the company’s collaboration with Sanofi. Unlike conventional medicines that primarily inhibit protein activity, targeted protein degraders are designed to promote the removal of specific disease-associated proteins through the cell’s natural protein disposal machinery. This approach has attracted considerable interest in pharmaceutical research because it offers opportunities to investigate biological targets that may be difficult to address using traditional drug discovery methods. Sanofi had initiated the Phase 1 first-in-human clinical trial of SAR448272, marking its transition from preclinical development into human investigation. However, on November 3, 2026, Nurix confirmed that Sanofi had decided to discontinue the study and terminate the program. The companies have not publicly provided a specific scientific, clinical or commercial reason for the decision. No clinical efficacy or safety findings were disclosed in the announcement, and the discontinuation should not be interpreted as evidence of a particular adverse clinical outcome.

Discontinuation Changes Nurix’s Future Milestone Opportunities

The termination of SAR448272 has financial implications for Nurix under its existing collaboration agreement with Sanofi. Following the decision, Nurix does not expect to receive additional development, regulatory or commercial milestone payments or future royalties associated with this specific STAT6 degrader program. These potential payments were linked to the candidate’s progress through clinical development, regulatory milestones and possible future commercialization. However, the decision does not terminate the entire Nurix-Sanofi collaboration. Nurix remains eligible for milestone payments and royalties from other previously licensed programs under the partnership, provided Sanofi chooses to advance those candidates into further development. The original collaboration, established in 2019, involved the use of Nurix’s proprietary drug discovery platform to identify molecules capable of promoting targeted protein degradation through E3 ligase activity. Nurix also stated that the discontinuation does not change its previously communicated financial outlook. The company reported $1.1 billion in cash, cash equivalents and marketable securities as of August 31, 2026, which it expects will support operations into the second half of 2029. This financial position provides resources to continue investing in its broader research and development activities while managing changes in its partnered pipeline.

Nurix Continues Advancing Its Broader Drug Pipeline

Despite the setback involving SAR448272, Nurix highlighted several other clinical-stage programs progressing across oncology and immunology. Its lead BTK degrader candidate, bexobrutideg, developed in collaboration with Roche, is advancing in a Phase 3 clinical trial for patients with chronic lymphocytic leukemia (CLL). The program represents an important part of Nurix’s targeted protein degradation strategy in cancer treatment. The company is also advancing NX-1607, a wholly owned CBL-B inhibitor, through multiple Phase 1b clinical cohorts involving patients with lung cancer, colon cancer, prostate cancer and melanoma. In addition, its IRAK4 degrader GS-6791/NX-0479, partnered with Gilead Sciences, is progressing through Phase 1 clinical development for potential applications in rheumatoid arthritis. These programs demonstrate that Nurix continues to pursue multiple approaches to targeted protein modulation and degradation across cancer and inflammatory diseases. The company is also maintaining a preclinical pipeline of potential protein degraders and degrader antibody conjugates. Overall, Sanofi’s decision to discontinue SAR448272 marks an important development setback for the collaboration but does not signal the end of Nurix’s broader research strategy. Continued progress across its remaining clinical programs will be important in determining the company’s future contributions to targeted protein degradation, oncology drug development and innovative treatments for immune-mediated diseases.

Source: Nurix Therapeutics, Sanofi press release