AEs similar across COVID-19 vaccines in Europe: Data Byte
At least 20 European countries have temporarily suspended the use of AstraZeneca’s COVID-19 vaccine due to concerns around thromboembolic events, but the rates of the side effects show little difference from the other two COVID-19 vaccines being distributed in Europe, and may not be above background levels in the general population.
According to the European Center for Disease Prevention and Control (ECDC), as of March 15 there had been 48.1 million doses administered across EU states, with Comirnaty from Pfizer Inc. (NYSE:PFE) and BioNTech SE (NASDAQ:BNTX) accounting for 37.5 million (78%) of the doses. The remainder were from AstraZeneca plc (LSE:AZN; NASDAQ:AZN) and Moderna Inc. (NASDAQ:MRNA).
Although AZ has been receiving all the attention related to thromboembolic events, an analysis of EudraVigilance adverse event data through March 13 shows little difference between the three COVID-19 vaccines as measured by events per million doses administered. Only AEs reported in the European Economic Area (EEA) were included in the analysis.
Estimates of the background rates of the AEs in published studies vary, but are generally similar to or higher than those reported in the vaccinated populations in EudraVigilance. For example, across seven studies of pulmonary embolism in different European countries incidence rates varied from 150-700 events per million people. Even the lowest of those rates is much higher than what’s been reported in the vaccinated populations.
According to Germany’s vaccines regulator, the Paul-Ehrlich-Institut, the primary reason for Germany’s suspension of AZ’s vaccine was due to a rise in cases of the rare adverse event of cerebral sinus thrombosis. According to EudraVigilance, AZ and Pfizer-BioNTech both reported three events of cerebral sinus thrombosis within the EEA, with no reports of the AE for COVID-19 Vaccine Moderna.
At a press briefing Tuesday, EMA Executive Director Emer Cooke stressed that the agency stands by its assessment of the risk/benefit profile of AZ’s vaccine. The agency’s Pharmacovigilance Risk Assessment Committee is reviewing the incidences of blood clotting events to see if there is any potential link to use of the vaccine; its scientific conclusions are due at an event planned for Thursday.
Associate Editor Paul Bonanos contributed to this report.