The Lancet, an authoritative medical magazine has published the results of the 1/2 phase of research on Sputnik Light vaccine. The scientists drew conclusions about the safety, immunogenicity and volunteers’ tolerability of the vaccine. The composition of this vaccine is identical to the first component of the classic version of Sputnik V. The study was funded by the Russian Direct Investment Fund, which promotes the vaccine.
The study was conducted on 110 healthy volunteers aged 18 to 59 years at Eco-Safety Clinical Center in St. Petersburg. "The results show that the vaccine was well tolerated and induced strong humoral and cellular immune response both in the seronegative and seropositive groups," the article says.
Scientists studied neutralizing antibodies (the most important in terms of preventing the virus get into the cells). In addition, cellular immunity and changes in the level of neutralizing antibodies were measured.
How did you get the protection after the vaccine?
Before vaccination, all the participants were tested for antibodies to coronavirus, and those who had them (14 people) were placed in one group, those who did not have antibodies (96 people) were placed in another. The authors of the article came to the conclusion that even a single injection for volunteers who had not previously had antibodies is enough to quickly get an immune response. Seroconversion (production of specific antibodies in the serum) was 100% by the 42th day.
A cellular immune response was formed in 96% of those who did not have immunity before vaccination as early as 10 days after the injection, scientists note. No significant statistical differences were found between the groups for this parameter, since there were few who had previously had immunity, but all of them developed cellular immunity after a single vaccination.
Side effects and vector immunity
The volunteers did not have any serious side effects after Sputnik Light vaccination, 5.5% had moderate side effects, the study says. Most of the reported systemic and local side effects were not serious - 66.4%.
“One-shot vaccines against SARS-CoV-2 compensate for the vaccine shortage, allowing the population to achieve immunity in a shorter time, thereby it helps to prevent new waves of Covid-19 around the world,” the scientists note.
"Our results show that Sputnik Light vaccine is safe and immunogenic for both seronegative and seropositive healthy adults. Thus, Sputnik Light can be considered not only for primary vaccination, but also as an effective tool for further revaccination or vaccination after a previous Covid-19 infection,” the article says.
