‘Vaccine Fatigue’? Merck Bets $9.2 Billion on ‘Not-a-Vaccine’ Flu Drug ‘Vaccine Fatigue’? Merck Bets $9.2 Billion on ‘Not-a-Vaccine’ Flu Drug November 22, 2025 by Suzanne Burdick, Ph.D. Merck is paying $9.2 billion to acquire a drug company primarily for an experimental antiviral flu-prevention drug, marketed specifically as “not a vaccine.” TrialSite News reported…