Sanofi will stop its Phase 3 MOBILIZE trial of riliprubart in chronic inflammatory demyelinating polyneuropathy after an independent monitoring board concluded the drug is unlikely to achieve sufficient efficacy. Sanofi said the committee saw no safety concerns, but favored futility based on interim analysis results. Riliprubart targets complement component C1s; the decision removes a late-stage opportunity for the program while intensifying competitive scrutiny of complement-inhibition approaches in CIDP. Investors also weighed potential read-throughs for rival programs in the same disease space. Sanofi said it is evaluating next steps, including whether to continue another Phase 3 trial, VITALIZE, which compares riliprubart with IVIg. The development follows a broader set of pipeline setbacks for the company.