The Covid-19 vaccine that Russia registered on Tuesday is expected to enter into civilian circulation on January 1, 2021, the media reported, citing the registration certificate.Russian Health Minister Mikhail Murashko said that teachers and medical workers will be the first to get the Covid-19 vaccine jointly developed by the Gamaleya Research Institute and the Russian Defence Ministry, the Tass news agency reported."We will begin the stage-by-stage civilian use of the vaccine. First and foremost, we would like to offer vaccination to those who come into contact with infected persons at work. These are medical workers. And also those who are responsible for children's health - teachers," the minister was quoted as saying.The Russian Health Minister said that two sites - the Gamaleya Research Institute and pharmaceutical company Binnopharm JSC - will be used for producing the vaccine.The head of the Russian Direct Investment Fund, Kirill Dmitriev, said that the country has received requests for one billion doses of the vaccine."We see a great interest abroad towards the Russian vaccine produced by the Gamaleya Research Institute. We have received preliminary requests for the purchase of over 1 billion doses of the vaccine from 20 states," Dmitriev was quoted as saying.He said that the country is ready to ensure production of over 500 million vaccine doses along with its foreign partners in five countries.Russia is planning to increase its production capacity further, he said, according to a Tass news agency report.As per details available at U.S. National Library of Medicine's ClinicalTrials.gov, a database of privately and publicly funded clinical studies conducted around the world, the "Gam-COVID-Vac" developed by the Gamaleya Research Institute has two components.The first component consists of a recombinant adenovirus vector based on the human adenovirus type 26, containing the SARS-CoV-2 S protein gene. SARS-CoV-2 is the virus responsible for Covid-19.And the second component consists of a vector based on the human adenovirus type 5, containing the SARS-CoV-2 S protein gene.During the clinical trial of the vaccine, a group of experimental participants received the drug in a booster version.They were given the second component of the vaccine three weeks after the first vaccination.