Sanofi scraps Phase 3 trial of riliprubart after CIDP treatment failure

Sanofi has abandoned its Phase 3 MOBILIZE study of riliprubart after the drug failed to treat refractory CIDP. The trial involved 140 patients across 134 global sites. Riliprubart is a C1s inhibitor designed to target the classical complement pathway of the immune system. Sanofi acquired Bioverativ for $11.6 billion in 2018. The deal was controversial, with critics questioning its high cost and long-term value.

The Bioverativ portfolio includes Enjaymo, another C1s inhibitor. Approved in 2022, Enjaymo was later sold to Recordati for $825 million. Another drug from the acquisition, Altuviiio, gained approval in 2023 for haemophilia A and has since generated around €325 million in sales by Q1 2026.

The failure of riliprubart marks a setback for Sanofi’s Bioverativ pipeline. Following the interim analysis, the company is now reviewing other ongoing studies of the drug. The abandonment of the MOBILIZE study raises further questions about the Bioverativ deal. Despite Altuviiio’s strong sales, the acquisition’s overall success remains uncertain. The $11.6 billion price tag is still not fully justified by its outcomes.