The Russian Sputnik V vaccine is 91.6% effective against symptomatic coronavirus, results of interim trials have suggested.
The preliminary findings are based on data analysis from more than 20,000 mostly white participants, three-quarters of whom received the vaccine. The rest received a placebo.
Serious adverse events were not considered to be associated with vaccination and the majority of adverse events reported were mild, including flu-like symptoms, injection site pain, and weakness or low energy.
The vaccine, which is backed by the Russian Direct Investment Fund (RDIF), is given in two injections 21 days apart. In the 21 days after the first dose, there were 16 cases of Covid-19 in the 14,964 people (0.1%) in the vaccine group and 62 cases of the disease in the 4,902 people (1.3%) in the placebo group .
The trial included 2,144 participants aged 60 and over; in this subset, the vaccine was 91.8% effective against symptomatic disease, the researchers wrote in The Lancet magazine.
Similar to the Oxford / AstraZeneca vaccine, Sputnik V is based on a modified version of the adenovirus, a virus from the common cold. This is designed to carry genetic instructions for making the coronavirus spike protein, which is passed into human cells. The manufactured coronavirus spike protein triggers an immune response to again protect Covid-19 disease.