FDA approves Merck's RSV shot for infants, ramping up competition with Sanofi and AstaZeneca
1. Merck's RSV shot, Enflonsia, receives FDA approval for infants. 2. Orders for Enflonsia expected to start in July before RSV season. 3. Merck competes with Sanofi's Beyfortus, which faced supply shortages. 4. Enflonsia shown to significantly reduce RSV-related hospitalizations. 5. Other companies also marketing RSV treatments for adults and pregnant women.