“ Protection Before Day One Vaccine: Seasonal Influenza Vaccines with Pandemic Coverage ” Request for Information (RFI) 1.0 Background Influenza viruses remain a persistent and evolving threat to public health in the United States and globally. Seasonal influenza epidemics cause significant morbidity and mortality each year, while novel zoonotic influenza subtypes retain the potential to trigger pandemics. A critical vulnerability in current pandemic preparedness is the time required—typically at least three months—between identification of a novel pandemic strain and deployment of strain-matched vaccines at scale. The Center for the Biomedical Advanced Research and Development Authority (BARDA) has led efforts to develop improved influenza vaccines and expand domestic manufacturing capacity, including initiatives to accelerate vaccine development timelines. However, limitations in current vaccine technologies result in a protection gap during the earliest phase of a pandemic. In a pandemic setting, early intervention is crucial to dampening the spread and impact of a novel virus. Prior modeling studies have demonstrated that a modestly effective but rapidly distributed vaccine can provide a greater benefit than a highly efficacious but delayed vaccine. Similarly, bolstering population immunity before a pandemic would lessen the damage caused by emergent influenza strains, even if the vaccine is only partially protective. BARDA refers to these vaccines as offering “Protection Before Day One”, with “Day One vaccines” providing some degree of protection at the outset of a pandemic. Day One vaccines, would: Deliver seasonal influenza protection; and Provide partial protection against emerging pandemic influenza viruses at the onset of a Public Health Emergency. Modeling suggests that Day One vaccines can not only reduce the total number of infections and peak infection rate but also delay the peak to allow more time for strain-matched pandemic vaccines to become available. In addition to the population-level benefits, Day One vaccines would also benefit individual vaccine recipients by reducing the risk of severe disease. Even with modest effectiveness, receiving a Day One vaccine could reduce an individual's hospitalization risk by 35%. Through this RFI, BARDA seeks to understand the availability of candidate Day One vaccines, including their development maturity, technical feasibility, manufacturing readiness, and regulatory considerations associated with vaccine candidates intended to meet this dual-benefit profile. Please see full Request for Information attached.