Why It Matters: R.S.V. can be lethal
The F.D.A. estimates that R.S.V. is associated with 6,000 to 10,000 deaths each year in adults 65 and older and at least 60,000 hospitalizations in that age group. It is a leading killer of children worldwide.
This winter, R.S.V. contributed to the “tripledemic” also involving flu and Covid cases that swamped children’s hospitals and some I.C.U. wards.
Background: Benefits and risks of the shots
On March 1, an F.D.A. advisory panel reviewed data from trials for two R.S.V. vaccines aimed at older adults, one from GSK and one from Pfizer. The panel recommended that the agency approve both.
The GSK vaccine was nearly 83 percent effective in preventing lower respiratory tract illness in adults 60 and older in a study of about 25,000 patients, according to data published in The New England Journal of Medicine. The virus can lead to pneumonia, which is far more worrisome for older adults and especially for those with underlying medical conditions like heart and lung disease or diabetes.
Pfizer’s R.S.V. vaccine for older adults is also expected to receive F.D.A. approval this month. In a large study of that shot, it was found to be nearly 67 percent effective in preventing R.S.V.-related illness.
The Pfizer and GSK vaccines were even more effective in treating older and sicker patients.
The advisers did learn of some rare side effects from the vaccine trials. In the days after the shots were given, two recipients of the Pfizer vaccine and one recipient of the GSK shot developed cases of Guillain-Barré, a condition where the immune system attacks the nervous system (but not the spine or brain), according to data given to the F.D.A. panel. The F.D.A. is requiring GSK to monitor the incidence of Guillain-Barré and another rare condition that was possibly related to the shot.
Moderna is also developing a vaccine for R.S.V. in older adults and said it expected authorization in the first half of this year. The company said a trial of 37,000 older adults showed 82 percent efficacy of the shot. The study was completed with “no safety concerns identified,” a Moderna news release said, though safety analyses were continuing.
AstraZeneca and Sanofi are also seeking F.D.A. approval of a monoclonal antibody treatment meant to protect infants and toddlers up to 2 years old from R.S.V. infections. The companies reported findings from a major study indicating that the therapy reduced confirmedillnesses by 75 percent after one shot, according to AstraZeneca.
Pfizer is seeking a separate approval for an R.S.V. vaccine given in the later stages of pregnancy to protect young infants.
What’s Next: When will the vaccines be available?
It will still be months before the vaccine is publicly available in the United States.
The Centers for Disease Control and Prevention is expected to follow the F.D.A.’s approval, most likely with a recommendation for use of the R.S.V. vaccines for older adults, possibly in June.
The GSK vaccine then would be available in the fall at local U.S. pharmacies, clinics and other health care settings, the company said.
GSK executives have said that supplies of the vaccine, which is manufactured mainly at a plant in Belgium, should be readily available once it’s approved for use. For Medicare patients with Part D drug coverage, there would be no out-of-pocket expense, Alison Hunt, a GSK spokeswoman, said. But the company has not released a price, although insurers typically cover much of the cost of many vaccines.
The company told investors this year that it hoped to gain approval from the European Union for its R.S.V. vaccine, and later in China. Last week, the European Medicines Agency did recommend approval of GSK’s vaccine for adults 60 and older.