Brazilian health authority Anvisa said late Monday that it would not recommend importing Sputnik V, the Covid-19 vaccine developed by Russia.
Anvisa said that critical safety tests had not been conducted and that questions about the vaccine’s development, safety and manufacture remained open.
Data on the effectiveness of the vaccine are “uncertain”, said Gustavo Mendes Lima Santos, manager for medicine and biological products at Anvisa, in a detailed presentation of the decision of the health authority. The presentation said “crucial questions” remained unanswered, including concerns about possible adverse events such as clotting.
A tweet from the official Sputnik V Twitter account – in Portuguese – was pushed back on Monday, saying the vaccine developers had shared “all the necessary information and documentation” with Anvisa. In another tweet he urged Anvisa: “We have no time to waste – let’s start saving lives in Brazil. Together.”
Russia uses Sputnik V in its mass vaccination campaign, and the vaccine has been approved in dozens of other countries in case of emergency. The introduction was mired in politics and propaganda, and President Vladimir V. Putin gave his approval for its use before the late trials began. It was denounced by Western scientists for months.
The Gamaleya Research Institute, part of the Russian Ministry of Health, developed the vaccine, also known as Gam-Covid-Vac. A peer-reviewed study published in The Lancet in February found the vaccine to have an effectiveness rate of 91.6 percent.
The skepticism of Western experts has mainly focused on the early approval rather than the design of the vaccine, which emerged from decades of research into adenovirus-based vaccines. Other Covid-19 vaccines are also based on adenoviruses, such as one from Johnson & Johnson using Ad26 and one from the University of Oxford and AstraZeneca using a chimpanzee adenovirus.
While the developers of Sputnik V have not yet released detailed data on adverse events observed during the trials, the Russian government has been using the vaccine to vaccinate its own citizens for months. Russia has also exported Sputnik V to Belarus, Argentina and other countries, suggesting that any harmful side effects that were overlooked during the trials have now come to light.
As vaccine supply problems worsened in Europe, the European Union Medicines Agency announced last month that it would review the Sputnik V vaccine after member states announced they would purchase the vaccine themselves.