The FDA's vaccine advisory committee met Sept. 17 to discuss Pfizer's request for a booster dose of its COVID-19 vaccine for everyone ages 16 and older. The committee voted against a booster for the general population, but voted to recommend the FDA authorize boosters for people ages 65 and older and those at risk of severe COVID-19.
The meeting only discussed authorization of Pfizer booster shots, not Moderna or Johnson & Johnson ones, as the FDA hasn't finished reviews of data for those two vaccines.
Seven takeaways from the meeting:
- The panel experts presented conflicting data on whether boosters are needed, as they discussed a complex array of data from a variety of sources, The New York Times reported. The experts said that vaccination is still powerfully protective against severe illness and hospitalization in the majority of people in all studies published so far, but that vaccines appear to be less effective against infections in people of all ages, especially those exposed to the delta variant, according to the Times.
- The cumulative data seems to suggest that only older adults may need boosters, according to the Times.
- Some experts expressed concern that the long-term benefit of boosters is unclear and that it's not feasible to repeatedly give boosters to the general population, the Times reported.
- Some noted that while antibodies are expected to wane over time, studies have so far indicated that immune cells that prevent severe illness remain strong. One study published this week showed steady levels of immune cells seven months after the second dose, according to the Times.
- The analysis Pfizer submitted as justification for its request for a booster dose came from real-world data collected in Israel. It was revealed during the meeting that Israel defines severely ill COVID-19 patients as anyone with an accelerated respiratory rate and oxygen levels below 94 percent. The CDC defines severely ill as meaning those sick enough to be hospitalized. The discrepancy may explain why Israel and the U.S. have reported such different outcomes in fully vaccinated people, the Times reported.
- Israeli experts told the vaccine committee they believe a booster dose of Pfizer's vaccine helped to dampen a fourth wave of COVID-19 caused by the delta variant, according to the Times. Israel's head of public health services, Sharon Alroy-Preis, MD, said that after offering boosters to the general population, the country is now averaging about half as many severe or critically ill patients than the health ministry had anticipated.
- The CDC's vaccine advisory panel is set to meet next week to discuss recommendations for Pfizer booster shots.