All participants given a Russian Covid-19 vaccine developed an antibody response and suffered no serious adverse side effects in the early-stage trials, according to results published in The Lancet medical journal.
Experts said the trials were still too small and early to prove the vaccine’s effectiveness and safety – and noted that there had not been a placebo comparison.
The trial took place in two Russian hospitals and involved 76 healthy adults aged 18 to 60.
Each participant was given a dose of the first part of the vaccine and then given a booster with the second part 21 days later.