The first COVID-19 vaccine to be approved was Sputnik V, which was developed by Russia’s Gamaleya National Center of Epidemiology and Microbiology. This Snapshot looks at some of the most common side effects identified in clinical trials, as well as some of the debates surrounding the vaccine’s possible safety issues.
The Gamaleya National Center of Epidemiology and Microbiology in Moscow, Russia, produced Gam-COVID-Vac, also known as Sputnik V, a COVID-19 vaccine. It is the first COVID-19 vaccine to be approved for use against the SARS-CoV-2 virus anywhere in the world.
The vaccine has been authorised by 64 countries, including Russia. Argentina, Iran, and India are among these nations. The European Medicines Agency is currently reviewing the vaccine in the European Union.
Sputnik V is a two-part adenovirus viral vector vaccine that has a 91.6 percent efficacy score.
Adenoviruses are viruses that are linked to the common cold and other illnesses. They function as a vehicle for the DNA instructions to generate the SARS-CoV-2 virus’s spike protein in the body. This prompts the immune system to produce antibodies against the spike protein, preparing the body for an infection.
The two doses both use a different type of adenovirus: the first uses type-26 (Ad26), and the second uses type-5 (Ad5). The use of two forms is intended to reduce the risk of the body producing antibodies against the adenovirus after the first dose, which may render the second dose ineffective.
Ad26 is used in the single dose of the Johnson & Johnson COVID-19 vaccine, which is also an adenovirus-based vaccine.
Common side effects
The vaccine’s efficacy and safety were reported in an interim review of phase 3 clinical trial results published in The Lancet in February 2021. According to the data, the following were the most common side effects:
According to the authors of the study, 45 out of 16,427 people who obtained the vaccine experienced severe side effects, such as deep vein thrombosis, hemorrhagic stroke, and hypertension. However, the independent data review committee concluded that none of these were linked to the vaccine, according to the report.
Despite these findings, there is still a lot of debate about the vaccine. The findings have been met with scepticism by experts, who point to Russia’s policy of early acceptance in August 2020, as well as the lack of publicly available raw data and protocol.
Risks of replication and the common cold
In their natural state, adenoviruses can reproduce in the body and cause illnesses like the common cold. Adenoviruses are modified in vaccines to suppress their ability to replicate. It was noted that the E1 gene was omitted from the Sputnik V vaccine in order to avoid replication.
Brazil, on the other hand, recently opposed the use of Sputnik V, citing replication issues. Quality control records showed that batches of the vaccine contained “less than 100 replication-competent particles per dose,” indicating that the adenovirus has a limited risk of replication, according to Anvisa, the Brazilian Health Regulatory Agency.
Shortly after, the Gamaleya National Center issued a press statement refuting Anvisa’s claims, claiming that Brazil’s decisions were “political in nature” and “had little to do with the regulator’s access to information or research.”
It noted that only non-replicating adenoviruses are used in the vaccine and listed other quality control measures.
Some scientists have criticised Russia for its lack of openness, while others have questioned Anvisa’s interpretation of the results. If the adenovirus is able to spread, most people will experience a moderate common cold as a side effect. The risks could be higher for people with compromised immune systems.
Risks of HIV vulnerability
Researchers raised questions about the possible risks of introducing Ad5 into COVID-19 vaccines after CanSino published phase 1 clinical trial data on Convidecia, another Ad5-based COVID-19 vaccine.
The adenovirus Ad5 present in vaccines could be associated with an increased risk of HIV acquisition, according to a 2008 study examining the effectiveness of an HIV-1 vaccine.
Although more research is required to back up this point, the researchers advise against using Ad5-based COVID-19 vaccines, particularly in areas of the world where HIV and AIDS are prevalent.