FDA found no stroke risk for seniors who received Pfizer booster

The Food and Drug Administration has seen no indication that older adults are at increased risk of stroke after receiving Pfizer’s recall of omicron, a federal health official said Thursday.

The FDA launched an extensive review of federal data after investigators from the Centers for Disease Control and Prevention detected a possible risk of stroke for seniors who received the Pfizer booster.

The CDC’s Vaccine Safety Datalink, which monitors serious reactions to vaccines, showed a possible risk of stroke in late November. The FDA independently reviewed data from the Centers for Medicare and Medicaid Services and its vaccine adverse event reporting system.

“So far, the data we’ve seen suggests no safety risk from bivalent boosters in those 65 and older,” Richard Forshee, deputy director of the FDA’s office of biostatistics, told the independent panel. agency vaccines.

The FDA reviewed CMS data from 4.25 million older adults who received Pfizer’s omicron booster and identified no increased risk of stroke. The agency’s review of VAERS data also found no increased risk.

The Department of Veterans Affairs also conducted a preliminary review of its database and did not identify an increased risk of stroke, Forshee said. The FDA also reached out to international partners and Pfizer to find out what they observed in their data.

“We have contacted a number of our international regulatory agencies, and various countries in Europe as well as Israel have not indicated any increased risk of stroke on their monitoring systems,” Forshee told the committee. FDA.

“We also contacted Pfizer and they looked through their global safety database and they saw no increase or signal of ischemic stroke in their systems,” Forshee added.

CDC investigators found that 130 seniors suffered strokes within 21 days of receiving Pfizer’s reminder among approximately 550,000 recipients in the VSD database. A man in his 60s has died a month after the stroke that was his likely cause of death, data showed Thursday.

Dr. Nicola Klein, the principal investigator of the CDC’s Vaccine Safety Datalink, said a statistical signal indicating a potential risk of stroke was first identified in late November and persisted through January, although the signal strength has diminished somewhat.

“I will say that in the data from just a few days ago, it’s subsided significantly and actually wasn’t reported last week for the first time,” Klein told the vaccine advisory panel. from the FDA.

However, investigators did a small analysis which indicated that older people who received both the Pfizer omicron booster and a high-dose or adjuvanted flu vaccine on the same day may have a higher risk of an accident. cerebrovascular disease, although the data are preliminary.

Although the FDA has not identified a stroke risk, the agency is initiating a study to examine potential safety issues that could arise from administering omicron Covid vaccines at the same time as high-dose influenza vaccines. dose or adjuvants, Forshee said. The study will help the agency prepare for the 2023-2024 respiratory virus season vaccination campaign, he said.