Sanofi-Synthélabo and Aventis merge to form Sanofi-Aventis (later Sanofi). Vaccines sit in Sanofi Pasteur, the Pasteur Mérieux Connaught lineage.

FDA approves Beyfortus (nirsevimab) with AstraZeneca for infants. Infant RSV prevention becomes a monoclonal antibody market.

Sanofi agrees to buy Dynavax for about $2.2B (HEPLISAV-B). Close still needs an 8-K. FY 2025 vaccines €7.936B, Beyfortus €1.781B.

FY 2025 call: 2026 vaccine sales guided slightly negative on US weakness. Beyfortus called out as not hit by the childhood-schedule edit.