March 28, 2024

On April 26, after anonymous vote, Anvisa rejected the request initiated by ten Brazilian states on the import of 30 million doses of Russian coronavirus vaccine Sputnik V. The agency expressed concerns regarding the quality, effectiveness and safety of the vaccine. The concerns were based on the lack of accurate data on the development, testing and production of the vaccine, which the Russian developer (Gamaleya National Center of Epidemiology and Microbiology) failed to provide. Moreover, there was no or insufficient information on the effectiveness of the vaccine, as well as its safety and quality control standards. In its official statements Anvisa ensured that it did not conduct its own microbiological study of the product but only analyzed documentation provided by the Russian developer. For this reason Antonio Barra Torres, head of Brazil’s federal health regulator Anvisa claimed: “We will not allow millions of Brazilians to use a drug, the effectiveness, quality and safety of which have not been confirmed.”

Russia-developed vaccine Sputnik V that is called by Moscow nothing short of a miracle and scientific breakthrough, has caused serious disagreements and even division among politicians and federal health regulator, the Brazilian National Health Surveillance Agency (Anvisa).

A few days later three Brazilian states Bahia, Maranhão and Sergipe represented new documents on the vaccine and demanded Anvisa to revise the decision. However, the regulative body claimed the additional information was, though, incomplete and upheld the decision. In particular, Anvisa believes that Sputnik V contains adenoviruses able to replicate, and it means the drug may harm recipients.

“The data we evaluated shows the presence of replicating virus,” Gustavo Mendes, general manager of medicines and biological products at Anvisa, said at the press conference held in April. Moreover, Mendes noted that Anvisa has analyzed the quality control documentation on other adenovirus-based coronavirus vaccines, for instance, those made by AstraZeneca and Johnson&Johnson, and found no evidence of replication-competent viruses in those companies’ final products. Gustavo Mendes added that Anvisa would not accept the vaccine until further studies’ results indicating safety of vaccine are obtained.

In April, the agency applied to Gamaleya National Center of Epidemiology and Microbiology asking to answer about 100 questions. The volume of missing information was important and was related to vaccine safety for the fetus, reproductive organs, elderly people, those who have already contracted coronavirus, the data on adenoviruses etc . The request ended with nothing.

Anvisa also reported on the lack of detailed information on the 63 cases of adverse effects and four deaths during the clinical trial. The Lancet article on Sputnik V’s efficacy trial mentioned no serious adverse effects or fatalities were deemed to be related to vaccination, reports Science.

Despite the fact that the worldwide standard has been intolerant for the presence of replicating adenovirus in the vaccines, Russian developers established an “acceptable” limit of 5000 replication-capable virus particles per one dose and claimed that each dose of Sputnik V contains “less than 100” such particles. “The limit for us is zero,” noted Anvisa during the press conference.

Both of the adenoviruses that make up Sputnik V, known as Ad5 and Ad26, are churned out by cultured human cells called HEK293 cells. The adenoviruses ferry the coronavirus spike gene to the vaccine recipient’s cells, which then make spike, prompting an immune response. To stop the adenoviruses from replicating once inside their human host, the vaccine developers removed a gene they need for reproduction, called E1. The viruses can copy themselves in HEK293 cells, which are engineered to have a stand-in E1 gene, but they are not supposed to be able to replicate once they are separated from the human cells and packaged in the final vaccine product.

It’s long been known that Ad5 can on rare occasions acquire the E1 gene from the HEK293 cells, converting what is supposed to be a crippled virus into RCA. Although adenoviruses typically cause mild colds, they can rarely kill people, and immunocompromised people who receive a vaccine that inadvertently contains RCAs could be at serious risk.

Angela Rasmussen, a virologist at the Vaccine and Infectious Disease Organization at the University of Saskatchewan criticized Sputnik V on Twitter saying: “The Sputnik V vaccine Ad5 vector is evidently replication competent. The makers apparently neglected to delete E1, so getting this vaccine means being infected with live adenovirus 5. Hence Brazil’s regulator correctly rejected it.”

Indeed, the stakes are high. Russia’s Sputnik V has been authorized and accepted in more than 60 countries that have adopted the vaccine and shown their interest in the purchase, and despite the fact that neither the World Health Organization nor the European Medicines Agency (EMA), a regulative body responsible for medicine’s verification in Europe, have not given their “green light” for Sputnik V yet.

Mr. Mendes specified that many of the countries that have authorized Sputnik V didn’t analyze the data themselves, but based their decision on its existing approval by other countries. Many Brazilian scientists have backed Anvisa’s decision, despite the urgency of the public-health crisis in the country, where Covid-19 has killed over 400,000 people.

Some other countries have cited similar problems connected with Russian vaccine. Last month, Slovakia’s drug agency refused to authorize the vaccine, saying that the developers of Sputnik V failed to provide 80% of the requested data. Sputnik V’s developers have called Slovakia’s decision an act of sabotage and breach of contract. The doubt in quality and safety of Sputnik V was originated from Slovakia’s State Institute for Drug Control (SUKL). Slovak regulative body concluded that the doses supplied to the country do not match the samples examined by EMA. “These vaccines have only the name in common,” the Slovak regulative body concluded.

The Brazilian politicians went further — they used justice to make pressure upon Anvisa. The Brazilian Supreme Court has ordered Anvisa to justify within 48 hours claims of missing documents needed to conduct a conclusive analysis of Sputnik V. It was made on the request filed by the authorities of the Maranhão state, which, like several other provincial governments, is waiting for the decision on the Russian vaccine.

Russian Direct Investment Fund (RDIF) which financed the development and the promotion of Sputnik V blamed Anvisa of spreading fake news and making “false accusations” regarding the presence of replicating adenoviruses in Sputnik V, threatening they would sue Anvisa.

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