MOSCOW (Reuters): Scientists gave Russia’s Sputnik V vaccine the green light on Tuesday saying it was almost 92% effective in fighting COVID-19 based on peer-reviewed late-stage trial results published in The Lancet international medical journal.

Experts said the Phase III trial results meant the world had another effective weapon to fight the deadly pandemic and justified to some extent Moscow’s decision to roll out the vaccine before final data had been released.

The results, collated by the Gamaleya Institute in Moscow that developed and tested the vaccine, were in line with efficacy data reported at earlier stages of the trial, which has been running in Moscow since September.

“The development of the Sputnik V vaccine has been criticised for unseemly haste, corner cutting, and an absence of transparency,” said Ian Jones, professor at the University of Reading, and Polly Roy, professor at the London School of Hygiene & Tropical Medicine.

“But the outcome reported here is clear and the scientific principle of vaccination is demonstrated,” the scientists, who were not involved in the study, said in a comment shared by The Lancet. “Another vaccine can now join the fight to reduce the incidence of COVID-19.”

The results were based on data from 19,866 volunteers, of whom a quarter received a placebo, the researchers, led by the Gamaleya Institute’s Denis Logunov, said in The Lancet.

Since the trial began in Moscow, there were 16 recorded cases of symptomatic COVID-19 among people who received the vaccine, and 62 among the placebo group, the scientists said.

This showed that a two-dose regimen of the vaccine – two shots based on two different viral vectors, administered 21 days apart – was 91.6% effective against symptomatic COVID-19.

The Sputnik V vaccine is the fourth worldwide to have Phase III results published in leading peer-reviewed medical journals following the shots developed by Pfizer and BioNTech, Moderna and AstraZeneca. Pfizer’s shot had the highest efficacy rate at 95%, closely followed by Moderna’s vaccine and Sputnik V while AstraZeneca’s vaccine had an average efficacy of 70%.

Sputnik V has also now been approved for storage in normal fridges, as opposed to freezers, making transportation and distribution easier, Gamaleya scientists said on Tuesday.

Russia approved the vaccine in August, before the large-scale trial had begun, saying it was the first country to do so for a COVID-19 shot. It named it Sputnik V, in homage to the world’s first satellite, launched by the Soviet Union.

Small numbers of frontline health workers began receiving it soon after and a large-scale roll out started in December, though access was limited to those in specific professions, such as teachers, medical workers and journalists.

In January, the vaccine was offered to all Russians.

“Russia was right all along,” Kirill Dmitriev, head of the Russian Direct Investment Fund (RDIF), which is responsible for marketing the vaccine abroad, told reporters on Tuesday.

He said the results supported Russia’s decision to begin administering Sputnik V to frontline workers while the trial was still underway, and suggested scepticism of such moves was politically motivated.

“The Lancet did very unbiased work despite some of the political pressures that may have been out there,” he said.

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