The Sputnik V vaccine developed by Russia is 91.6 percent effective at protecting against symptomatic COVID-19 – comparable to currently approved Western jabs, according to a peer-reviewed study published in The Lancet Tuesday.
The data comes from a phase 3 study, with nearly 20,000 participants from a number of hospitals and clinics in Russia participating in the two-dose schedule. From 21 days after the first dose, there were 16 cases of symptomatic COVID-19 in the vaccine group versus 62 cases in the placebo group, researchers reported. There were no cases of “moderate or severe” coronavirus infections in the vaccinated group 21 days after the first dose.
The clinical trial also analyzed people over the age of 60 and found the jab to be 91.8 percent effective, based on 2,144 participants.
The issue of efficacy in the elderly has made the debate over the Oxford / AstraZeneca vaccine persistent due to a lack of data. Last week, German experts recommended limiting admission to people under 65 until more data is collected.
The Sputnik V vaccine is based on an adenoviral vector, which uses a modified version of the common cold to induce cells to produce the spike protein found on the coronavirus. The body then makes antibodies that target the protein, protecting the immune system. The Russian shot differs from the Oxford / AstraZeneca shot – which is based on similar technology – because it uses two different viruses in each shot.
The study authors say the two-pronged vaccine strategy “may help create a more potent immune response” because it lowers the risk of the body developing resistance to the shot, which would otherwise reduce the effectiveness of the second injection.
However, the study also notes that because cases of coronavirus were not discovered until after participants reported symptoms and then tested, efficacy only covers symptomatic cases of the coronavirus. More research is needed to assess efficacy for cases without symptoms, the study concluded.
In the EU, only Hungary has allowed the use of the Russian shot, although discussions are underway with the European Medicines Agency. Serbia and Belarus have both greened the vaccine. A spokesman for the Russian Direct Investment Fund, which is responsible for promoting Sputnik globally, said it plans to begin reviewing the jab with the EMA this month.
The clinical trial is underway and aims to involve approximately 40,000 participants in total.
In a written commentary, Ian Jones, a professor at the University of Reading, and Polly Roy, a professor at the London School of Hygiene & Tropical Medicine, noted that “the result reported here is clear” despite all criticism of the lack Sputnik transparency and the “inappropriate haste” of its development.
“Another vaccine can now join the fight to reduce the incidence of COVID-19,” they said.