The following is an excerpt from Time.
Pfizer Inc.’s vaccine to protect newborns from RSV received backing from U.S. regulatory advisers for use in pregnant mothers to protect their newborns, handing the drugmaker a win in the race to dominate immunization against the virus.
All 14 members of the committee that advises the Food and Drug Administration recommended the vaccine as effective for use in pregnant women.
In a separate question about safety, 10 panelists voted in favor of it and four voted against, saying they were concerned about pre-term births among participants.
The FDA isn’t required to follow its advisers’ recommendations, but often does.
Respiratory syncytial virus normally causes a cold in otherwise healthy people but can be dangerous for the elderly and young children.
Rival GSK Plc’s RSV vaccine has already been approved for use in older adults and Pfizer is expected to get the green light for that group later this month.
While GSK beat Pfizer to regulatory approval for an RSV vaccine for older adults, the British company stopped enrolling RSV trials for pregnant women due to an increase in pre-term births that it’s still studying.
Pfizer also reported a higher rate of premature births among pregnant mothers who received its vaccine than among those who got a placebo, but the difference wasn’t statistically significant, FDA staff said in a report released before the advisory meeting.
Several advisory committee members brought up the issue of pre-term births during the all-day meeting Thursday.
GSK’s data on premature birth is “hanging over” Pfizer’s vaccine, said one member, Paul Offit, director of the Vaccine Education Center at the Children’s Hospital of Philadelphia.
Lack of data about co-administering the RSV shot with other vaccines is also worrying, said Hana Mohammed El Sahly, chair of the panel and professor at Baylor College of Medicine. Both voted against recommending the vaccine for safety reasons.
In pregnant women, Pfizer reported vaccine efficacy of 81.8% against severe cases of RSV in the first 90 days of life in newborns, and 69.4% in the first six months.