The calculations were based on preliminary data obtained 42 days after the first dose MOSCOW: Russia’s Sputnik V coronavirus vaccine is 95 percent effective according to a second interim analysis of clinical trial data, its developers said on Tuesday. The calculations were based on preliminary data obtained 42 days after the first dose, Russia’s health ministry, the state-run Gamaleya research center and the Russian Direct Investment Fund (RDIF) said in a statement. They did not note the number of cases used to make the calculation, however.