MOSCOW, August 21. /TASS/. The proposal of the Russian Direct Investment Fund (RDIF) to use the Sputnik Light shot to additionally inoculate people who had the Pfizer vaccine has a scientific basis and will help to improve the effect of the first two jabs, head of the Gamaleya Center Alexander Gintsburg told TASS.
"Pfizer has a problem with the Delta variant which is now responsible for 90% and in some regions of the world 100% [of the cases]. Their efficacy is not as high as they declared against the original strain, their efficacy halved to almost 50-40% which is not observed in Sputnik V. Therefore, the RDIF proposal is quite logical and scientifically based," the scientist said.
The RDIF announced its proposal to use Sputnik Light for a third jab for those vaccinated with Pfizer on August 11. Moreover, it suggested cooperation to AstraZeneca last fall.
Earlier, scientists said that the Pfizer efficacy dropped from 76% to 42% amid the Delta surge. At the same time, the Russian Health Ministry said that the Sputnik V is 83% effective against this strain.