Science’s COVID-19 reporting is supported by the Heising-Simons Foundation. When the Kremlin last month said Russian President Vladimir Putin had received the first dose of a homegrown COVID-19 vaccine, a guessing game began. Had he gotten Sputnik V, which Russia had given emergency use authorization—a world first—in August 2020 after testing in just 79 patients? Or had Putin been given another COVID-19 vaccine that Russia had sanctioned with much less fanfare—and with equally sparse evidence that it works? Putin and state officials wouldn’t say, but Russia’s second COVID-19 vaccine, known as EpiVacCorona and first authorized in October 2020, has begun to emerge from the shadow of Sputnik V, bringing controversy of its own. Developed by VECTOR, the famed State Research Center of Virology and Biotechnology that once studied bioweapons and now is one of two global repositories of the eradicated smallpox virus, the vaccine is key to the country’s plans to combat the pandemic. Russia began to offer it to small numbers of people last year, plans to administer 1.5 million doses per month by this summer, and aims for a bigger national campaign.