Americans as young as 18 with a chronic condition can now receive an RSV vaccine after Pfizer snagged expanded FDA approval this week.
The shot, Abrysvo, is now approved for people 18 to 59 who are at increased risk of lower respiratory tract disease caused by the virus, significantly expanding beyond the 60-and-older demographic the shot was previously greenlit for.
The expanded approval, announced Tuesday, gives Pfizer the broadest label among the three adult vaccines on the market. GSK previously offered the only approved product in patients younger than 60, available for people 50 to 59 as well. Moderna’s shot, mRESVIA, is approved for patients 60 and older. Sanofi and AstraZeneca’s monoclonal antibody is a prophylactic available for infants.
It’s unlikely, however, that many people in the younger age group actually get the shot this season, given that the CDC still only recommends the shots for select people 60 and older. Market data have shown that the shots aren’t being administered as widely this year compared with last year — their first on the market.
Tomorrow, the CDC’s Advisory Committee on Immunization Practices, or ACIP, is meeting to discuss RSV vaccine co-administration data from Moderna and Pfizer and data from GSK on immunocompromised populations. The group isn’t expected to reconsider its RSV vaccine recommendations again until next year.
Pfizer’s new label was based on Phase 3 immunobridging data, in which immune response markers are compared to data in older populations where efficacy was studied. Vaccine manufacturers use immunobridging to infer the effectiveness of vaccines in subpopulations studied after a pivotal trial. Pfizer said it plans to publish the data in a peer-reviewed journal and present them at an upcoming scientific meeting.
Despite the expanded indication, the CDC adopted RSV recommendations in June that centered on people 60 and older. Those recommendations narrowed slightly from the year prior. Previously, the CDC recommended that patients 60 and older consult a healthcare provider about getting a shot; the new guidelines recommend a shot for adults ages 60 to 74 who are at higher risk, and for all adults 75 and older.
The CDC’s recommendations are crucial for guiding vaccine uptake because insurers must cover inoculations that the agency adds to its guidelines. Though any patient in an FDA-approved population can get a shot, people outside of the CDC’s recommended groups may pay out of pocket.