Called Enflonsia and developed by Merck & Co., the drug is an antibody intended to prevent illness from RSV, which can be particularly severe in young children.

Merck's shot will compete against a similar blockbuster treatment from Sanofi and AstraZeneca called Beyfortus, which was in short supply nationwide during the 2023 RSV season due to unprecedented ...

Merck plans to make Enflonsia available for physicians and healthcare administrators to order in July 2025. Shipments will be delivered before the start of the 2025-2026 RSV season.

Merck & Co., Inc. (NYSE:MRK) is one of the best wide moat stocks to buy now. On June 9, Merck’s preventative antibody shot received authorization from the U.S. Food and Drug Administration (FDA).

FDA approves Merck's RSV shot for infants, ramping up competition with Sanofi and AstraZeneca By Annika Kim Constantino, CNBC • Published June 9, 2025 • Updated on June 9, 2025 at 4:15 pm ...