The gap between the two shots of the Sputnik V coronavirus vaccine can be extended up to 180 days and it will remain effective, the Russian Direct Investment Fund (RDIF) said today, according to Reuters.
Guyana has been awaiting the second doses for Sputnik V for more than a month and the Ministry of Health here is still to explain why it was not supplied with even amounts of the first and second doses which utilise different strains of the adenovirus.
An official at the RDIF, which markets the vaccine abroad, made the comments in a statement after some countries decided to widen the gap between the first and second doses of the vaccine developed in Russia, Reuters said.
Kazakhstan has stated that a longer interval between shots provides a stronger immune response. Argentina has widened the gap to prioritise ensuring that as many people as possible receive at least a single dose.
Alexander Gintsburg, director of the Gamaleya Institute which developed the vaccine, said in April that the gap between the shots could be increased to 90 days.
The RDIF official quoted Gamaleya trials as showing longer gaps had secured a better immune response, but provided no further details of the trials. The official supplied the statement after a Reuters request for comment, and denied it was related in any way to Russian deliveries of Sputnik V.
RDIF has notified all foreign partners and vaccine buyers that prolonging the gap between doses to 90 days helps to slightly increase the immune response, the official added.
Russia’s vaccine roll-out involves giving people the second doses of Sputnik V after 21 days.
