The Food and Drug Administration has approved GSK’s respiratory syncytial virus (RSV) vaccine for at-risk adults starting from age 50, the company announced on Friday. This marks the first RSV vaccine authorized for use in this age group to protect against the virus.
GSK, a global vaccine and drug manufacturer, requested the FDA in February to extend the vaccine’s approval beyond the initially approved group of adults aged 60 and older. Data showed a similar immune response in adults vaccinated from this younger age group. GSK plans further trials for adults aged 18 to 49, with results expected later this year.
Pfizer and Moderna, which also produce RSV vaccines approved for adults 60 and older, are testing their vaccines in younger adults. Pfizer is preparing to submit positive data for its shot down to age 18.
Next, the Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices (ACIP) must recommend GSK’s vaccine for adults aged 50 to 59. Their endorsement, expected in meetings this June or October, would facilitate insurance coverage.
Vaccinating adults in their 50s against RSV offers public health benefits, as concluded by a CDC workgroup last year, although the benefits are narrower compared to older adults whose risk increases significantly with age. In adults under 60, pre-existing medical conditions contribute more to the severity of RSV infections.
Dr. Phil Dormitzer, GSK’s Senior Vice President and Global Head of Vaccines Research and Development, noted that the vaccine’s safety profile in this younger group is “relatively comparable” to that in older adults, with some side effects appearing stronger due to better immune responses.
The CDC panel has previously considered rare but serious cases of Guillain-Barré syndrome (GBS) linked to RSV vaccines. Approximately 1.5 cases of GBS per million doses of GSK’s vaccine have been reported. However, GSK’s trials did not find any concerning trends of GBS in the 50 to 59 age group.
The CDC panel will also discuss the potential need for booster shots for RSV. GSK plans to present more trial results in June, exploring boosters given up to three years after the initial shot. Dormitzer emphasized the importance of determining the duration of protection, which currently appears to last for more than one season.
