Anvisa is requesting the inclusion of possible side effects
By Karine Melo
Brazil’s national sanitary regulator Anvisa has requested the inclusion of possible side effects following reports of thromboembolic events with thrombocytopenia (low platelet count) under “Warnings and Precautions” in the text of the package insert for the Oxford/AstraZeneca/Fiocruz vaccine against the novel coronavirus.
“These are very rare cases of blood clot formation linked to thrombocytopenia—a reduction in the number of platelets (cell fragments that help clot the blood). In some cases, the bleeding may be associated with vaccine use. The cases were reported in a few countries,” Anvisa declared.
The information was published in a statement released by the drug authority on Wednesday (Apr. 7). In the document, Anvisa argues that vaccination should continue, as risks far outweigh the benefits.
In Brazil, with over 4 million doses of this vaccine administered thus far, a total of 47 suspected cases of adverse thromboembolic events have been reported, only one of which linked to a low platelet count. The cases were registered on VigiMed, the network used for the notification of adverse events associated with the use of vaccines and drugs in the country.
Despite the notifications, Anvisa said that no direct, causal link has yet been established between the 47 suspected cases and the use of the vaccine in Brazil. Specific risk factors for this adverse effect have also not been detected.
The request for changing the text in the package insert of the Oxford/AstraZeneca/Fiocruz vaccine comes as part of Anvisa’s ongoing monitoring efforts.
