Sanofi halted its Phase 3 MOBILIZE trial of riliprubart in chronic inflammatory demyelinating polyneuropathy (CIDP) after an independent monitoring board concluded the antibody was unlikely to achieve sufficient efficacy. Sanofi said there were no new safety concerns, but efficacy was not expected to reach statistical goals at interim analysis. The decision is another late-stage setback for Sanofi’s autoimmune pipeline as the company evaluates next steps for the program and whether to continue other Phase 3 work, including VITALIZE. Investors also looked to potential implications for rival complement inhibitors in CIDP, given the class-wide sensitivity to efficacy signals. The trial enrolled patients not helped by standard-of-care medicines, reinforcing that the stop decision reflects performance in a more difficult-to-treat population. Sanofi’s review of the riliprubart future now becomes central for complement-inhibition strategy in CIDP, a space with mounting competitive pressure.