After opening an inquiry into a potential safety issue identified by one of its monitoring systems, the Centers for Disease Control and Prevention stated on Friday (January 13, 2023) that it is “very unlikely” that the Pfizer omicron booster poses a risk of stroke for elderly patients.
In a statement published on its website on Friday (January 13, 2023), the CDC stated that the Vaccine Safety Datalink tracking system discovered a potential stroke risk in persons 65 and older who had the Pfizer booster dose that targets the omicron Covid variety. A CDC spokesperson said this issue was first detected in late November.
“By mid-December, the CDC concluded the concern was persisting and launched an investigation into whether seniors are more likely to have a stroke in the first 21 days after receiving the Pfizer booster,” the spokesperson said. A similar preliminary signal was not detected for Moderna’s booster.
Out of the approximately 550,000 seniors who received the Pfizer omicron booster shot, the VSD monitoring system discovered that 130 patients aged 65 and older experienced a stroke within 21 days of receiving the dose, according to the CDC spokeswoman. No deaths have been reported. The Washington Post earlier reported the news.
According to the CDC, no other surveillance system has so far identified a comparable safety concern for the Pfizer booster. Investigators have not found an increased risk of stroke following the Pfizer booster after reviewing data from the Center for Medicare and Medicaid Services, the Department of Veterans Affairs, the Vaccine Adverse Reporting System and Pfizer’s global safety database.
“Although the totality of the data currently suggests that it is very unlikely that the signal in VSD represents a true clinical risk, we believe it is important to share this information with the public, as we have in the past, when one of our safety monitoring systems detects a signal,” the CDC said in the post on its website.
According to a statement released by the CDC on Friday, monitoring systems frequently pick up safety signals that are caused by things other than the vaccine. The agency spokeswoman stated that in the upcoming weeks, investigators want to have a clearer picture and more information.
The investigation will be discussed at an upcoming meeting of the Food and Drug Administration’s panel of independent vaccine experts on Jan. 26.
In a statement Friday, Pfizer said there is no evidence to conclude that ischemic stroke is associated with company’s Covid vaccine. Neither Pfizer and its German partner BioNTech, nor the CDC or the FDA, have observed such an association in numerous other monitoring systems in the U.S. and globally, company spokesperson Kit Longley said.
“Compared to published incidence rates of ischemic stroke in this older population, the companies to date have observed a lower number of reported ischemic strokes following the vaccination with the omicron BA.4/BA.5-adapted bivalent vaccine,” Longley said.
The CDC has not changed its recommendation for the Pfizer omicron shot. Everyone who has finished their primary vaccination series and is at least five years old is eligible for the booster. The third dose in the primary series is given to the youngest children, who range in age from 6 months to 4 years.