The Indian COVAXIN vaccine was 77.8 percent effective in trials 
8 percent in preventing the onset of symptoms of coronavirus infection. The results of the third phase of clinical trials of the drug were published in the journal The Lancet.
In the third phase of clinical trials, more than 24.4 thousand Indian residents aged 18 to 97 years took part, who were randomly divided into two groups. Some (12,221 people) received two doses of the drug, others a placebo. Of almost 17,000 initially seronegative patients, PCR tests for COVID-19 were positive in 130 people. Among the 8471 vaccinated people, 24 people were infected, among 8502 people in the placebo group – 106 people, which makes it possible to estimate the effectiveness of the vaccine at 77.8 percent.
A total of 16 cases of severe COVID-19 were recorded – one in the experimental group and 15 in the placebo group. At the same time, the researchers note that these data are preliminary and need to be confirmed on a larger sample. Only 12 percent – in both the experimental and placebo groups – reported side effects after receiving the vaccine, none of which were serious.
Measurements taken one month after receiving the second dose showed that COVAXIN caused strong humoral – antibody-linked – immune response. Antibody activity in neutralizing coronavirus remained unchanged with the alpha variant, but decreased slightly for other variants of concern – in particular, delta. A preliminary analysis conducted by the researchers showed that the vaccine against infection with the delta variant of SARS-CoV-2 is 65 percent.