Sanofi stopped its Phase 3 MOBILIZE trial of riliprubart in chronic inflammatory demyelinating polyneuropathy (CIDP) after an independent monitoring board concluded the study was unlikely to provide sufficient efficacy. Sanofi said there were no safety concerns flagged, but interim analysis pointed to futility on efficacy. The trial tested riliprubart in patients who were not helped by standard-of-care therapies. Sanofi also indicated it is evaluating the future of the program, including whether to continue a second Phase 3 trial, VITALIZE, which compares riliprubart against IVIg. The stop is the latest setback for Sanofi’s pipeline execution as competitors continue to push into the complement inhibitor space for CIDP. Dianthus Therapeutics’ similar-target approach has also been under scrutiny after the market interpreted Sanofi’s results as potentially informative for the class. For investors, this is a near-term risk adjustment for late-stage autoimmune development in CIDP—and a reminder that interim reads can quickly change competitive narratives.