The scientists wrote in ‘The Lancet’ about two studies, carried out between June 18 and August 3, by the Russian Ministry of Health and the Ministry of Defence.
Each study involved 38 healthy adults between 18 and 60 years of age. After their vaccination, they were followed up for 42 days. In the first three weeks they all developed antibodies.
After Moscow’s announcement in August, numerous researchers and some countries expressed doubts about the efficacy and safety of Sputnik-V, because there was no publicly available data on the tests carried out.
The Russian scientists now acknowledge in The Lancet that extensive and long-term studies are needed, as well as further follow-up, to determine the “long-term safety and efficacy” of the vaccine.
The third test phase, which has already started, will last at least six months, according to the State Institute of Epidemiology and Microbiology Gamaleja in Moscow, which developed the vaccine.
It is only during this phase that a candidate vaccine is tested on a large number of people to determine whether and how well it protects against infection and what side effects occur.
The first volunteers in Moscow will receive the vaccine next week, according to mayor Sergey Sobyanin.
The Russians want to start vaccinating as of September, without waiting for the results of the third and final phase of the clinical tests.
According to the World Health Organisation, a total of 176 candidate vaccines are under development all over the world.
Of these, 34 are at the clinical testing stage, which means that tests on humans have been started. Eight vaccines are already in the third testing phase.