Sputnik V shot to protect against new mutations of the coronavirus is producing strong results, researchers said on Saturday.Last month President Vladimir Putin ordered a review by March 15 of Russian-produced vaccines for their effectiveness against new variants spreading in different parts of the world."(A) recent study carried out by the Gamaleya Centre in Russia showed that revaccination with Sputnik V vaccine is working very well against new coronavirus mutations, including the UK and South African strains of coronavirus," said Denis Logunov, a deputy director of the centre, which developed the Sputnik V shot.Results of the trial are expected to be published soon, but this was the first indication of how the tests are going.