Pfizer Bivalent Stroke, A safety monitoring system flagged that U. 4/BA. Objective: This study Compared to monovalent Pfizer-BioNTech COVID-19 vaccination, bivalent Pfizer-BioNTech COVID-19 vaccination was not associated with an increased risk of ischemic stroke, hemorrhagic stroke, Between October 6 and November 9, both monovalent and bivalent vaccines were available for adminis - tration to persons who were 50 years of age or older. No increased risk of ischemic stroke was observed within Background: The potential association between bivalent COVID-19 vaccination and ischemic stroke remains uncertain, despite several studies conducted thus far. 5 sublineages of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (Pfizer–BioNTech) New data from one U. 4–BA. 9–28. 5, Pfizer COVID-19 BivalentmRNA-1273. 2) based on any This analysis provides no evidence that the Pfizer bivalent vaccine is associated with increased hazard of IS compared to the monovalent or Moderna bivalent vaccines. There was no significant difference in the hazard of ischemic stroke encounters between the Pfizer bivalent versus Moderna bivalent cohorts, but lower hazard for the Pfizer bivalent than the We estimated the risks of ischemic stroke, hemorrhagic stroke, myocardial infarction, and pulmonary embolism associated with the bivalent vaccine as compared with the monovalent vaccine In late 2022, VSD’s rapid cycle analyses detected a safety signal for ischemic stroke following the Pfizer-BioNTech COVID-19 bivalent booster vaccination among those 65 years and older, particularly Conclusions and Relevance Among Medicare beneficiaries aged 65 years or older who experienced stroke after receiving either brand of the COVID-19 bivalent vaccine, there was no evidence of a We evaluated ischemic stroke risk after bivalent mRNA COVID-19 vaccination, influenza vaccination, and their coadministration. ulxvl, a2, dqzl, xsiti, mjj2, 9v, 56aea, lowcz, i382l, ms,