The announcement was the latest in a flurry of breakthroughs as several vaccine makers worldwide published preliminary data showing efficacy rates of 90 percent and higher.
Countries are hoping to begin inoculating their populations by year’s end or in early 2021 to stop a pandemic that has claimed the lives of nearly 1.4 million people.
Russia was one of the first to announce the development of a vaccine in August — dubbed Sputnik V after the Soviet-era satellite — but before the start of final clinical trials.
In statement on Tuesday, the vaccine’s developers said preliminary data after trials involving thousands of volunteers showed “an efficacy of the vaccine above 95 percent” after a second dose.
Russia’s health ministry, the state-run Gamaleya research center and the Russian Direct Investment Fund (RDIF) said in the statement they expected the vaccine to record an even higher effectiveness after the next analysis.
“No unexpected adverse events were identified as part of the research,” it said, though some of those vaccinated suffered short-term effects including fever, weakness, fatigue, and headache.