The Food and Drug Administration on Wednesday proposed the first public review of Pfizer's request for a coronavirus booster injection, two days before an external expert advisory committee meets to recommend whether or not the agency should approve. company demand.
This also comes in the midst of a big disagreement over the need for boosters between the career scientists of the agency and the top Biden Health o officials , who have already started planning a large relaunch campaign for this fall.
In a 23-page document reviewing the company's claim, regulators reviewed safety and immune response data from approximately 300 adults who were boosted with the Pfizer-BioNTech vaccine six months after their second dose, finding an enhanced immune response in study participants, even as they said the coronavirus vaccines were powerfully resistant.ment to severe forms of Covid-19. There were no serious safety issues associated with the booster injection, regulators reported.
Pfizer said in a separate archive that one month after a third injection, the levels of neutralizing antibodies against the Delta variant in a subgroup of trial volunteers were between five and about seven times higher than they were a month after the second dose. 96% to about 84% six months after the second injection, although it has remained stable against serious illnesses.
Pfizer argued in its record that the decline of theThe potency of the vaccine was the main reason for the breakthrough infections among those vaccinated in Israel, which relied almost exclusively on the Pfizer vaccine and vaccinated its population faster than the United St eats.
But the FDA regulators wrote that while declining immunity is a potential factor in major infections, other variables, including the Delta variant, may have contributed to the cases as well.
In an interview, Pfizer officials admitted that the company's recall study was quite small. But they said the data they provided meets F.D.A. criteria. to justify the third shots for people 16 years of age and over. Pfizer has another much larger recall study underway, the results of which are expected this fall.
The FDA analysis noted that Pfizer provided data on the immune response against the Delta variant, by far the dominant variant in the United States, in just two dozen people. Understanding the effectiveness of boosters against variants would likely be essential for the examination of F.D.A., the paper suggests. "The available data should support the effectiveness of the booster dose, especially primarily against currently circulating variants," the regulators wrote.
L The analysis also suggested that regulators cautiously assess Israel's studies, which senior officials in the Biden administration said were critical to their decision to recommend launching a recall campaign this month. Israel already provides booster shots to most of its population.
"Although observational studies may provide insight into efficacy in the real world, there are known and unknown biases that can affect their reliability, ”the regulators wrote. Studies in the United States "may most accurately represent the effectiveness of the vaccine in the American population," they added.