Russia's Sputnik V coronavirus vaccine is 95 per cent effective according to a second interim analysis of clinical trial data, AFP reported quoting the vaccine's developers.

The two-dose vaccine will be available on international markets for less than $10 per dose, they said, and will be free for Russian citizens.

It can be stored at between two and eight degrees Celsius, they said, instead of the temperatures below freezing required for some other vaccines.

The calculations of its effectiveness were based on preliminary data obtained 42 days after the first dose, Russia's health ministry, the state-run Gamaleya research centre and the Russian Direct Investment Fund (RDIF) said in a statement.