FDA Expands Indication for RSV Vaccine Abrysvo to Include Adults Aged 18 to 59 with Chronic Conditions
Pfizer announced the FDA approval on October 22 that makes Abrysvo now the RSV immunization with the broadest indication for adults, the company said.
The FDA has approved Abrysvo (RSVPreF; Pfizer), for prevention of respiratory syncytial virus (RSV) in adults aged 18 to 59 years who have chronic conditions that place them at increased risk of lower respiratory tract disease caused by the virus. The bivalent prefusion vaccine is now the only RSV vaccine indicated for adults younger than age 50, according to an announcement from Pfizer.1
The approval adds the indication to existing labeling for RSV protection in adults aged 60 years and older and to its approval as the only RSV immunization approved for pregnant women to protect infants from birth to age 6 months.1
The data supporting the FDA’s decision are from a substudy included in Pfizer’s pivotal phase 3 MONeT clinical trial for which the company announced topline results in April. The early data on the safety, tolerability, and immunogenicity from MONeT2 demonstrated neutralizing responses against both A and B strains of RSV in adults aged 18 to 59 years with a range of chronic conditions. Those findings were noninferior to data reported earlier from Pfizer’s phase 3 RENOIR3 trial of RSVPreF in a cohort of adults aged 60 years and older. RENOIR served as the registration trial for approval of RSVPreF by the FDA in May 2023 in this older population.
The vaccine’s safety profile in the high-risk cohort was consistent with previously reported studies, according to Pfizer.
“RSV represents a significant threat to younger adults with certain chronic conditions. After decades of vaccine research…we now have the opportunity to help alleviate the burden of RSV in this high-risk adult population,” Aamir Malik, Pfizer chief US commercial officer and executive vice president, said in the news release.1
Nearly 1 in 10 US adults between 18 and 49 years of age live with a chronic condition that increases their risk of contracting RSV and becoming ill enough to require hospitalization; among the population aged 50 to 64 years, the proportion at similar risk rises to approximately one-quarter (24.3%).4 Among the underlying chronic conditions that enhance susceptibility to the infection are obesity, chronic obstructive pulmonary disease, heart failure, chronic kidney disease, and asthma, according to the CDC.4
Brief Abrysvo History
In June 2024, the Advisory Committee on Immunization Practices (ACIP) voted to update its recommendation of RSV vaccines for use in adults aged 75 years and older and adults aged 60 to 74 years who are at increased risk for severe RSV disease. In August 2023, the FDA approved Abrysvo to prevent LRTD and severe LRTD caused by RSV in infants from birth up to 6 months through vaccination of pregnant women at weeks 32 through 36 of gestation. The next month, the ACIP recommended the maternal immunization to help protect newborns from RSV seasonally with the vaccine administered from September through January in most of the continental United States.
According to labeling approved by the FDA, Abrysvo has the broadest indication for RSV protection in adults, that is, for:
- the prevention of RSV-LRTD in people 60 years of age and older
- the prevention of RSV-LRTD in people 18 through 59 years of age who are at increased risk for LRTD caused by RSV
- pregnant individuals at 32 through 36 weeks gestational age for the prevention of LRTD and severe LRTD caused by RSV in infants from birth through 6 months of age
