Russia announced on Tuesday that its coronavirus vaccine was 95 per cent effective on par with two other leading vaccines – but the lack of full scientific data has left some questions unanswered.
Russia approved Sputnik V as the world’s first vaccine against Covid-19 in August even though the trials were still ongoing after President Vladimir Putin announced that his own daughter was inoculated.
The interim analysis of clinical trial data has shown that Sputnik V was 95 per cent effective 42 days after the first dose was administered, the Russian Direct Investment Fund which is backing the vaccine’s development at the Gamaleya Centre in Moscow said in a statement on Tuesday.
The calculations were based on the trial of 18,794 volunteers who received both the first and second doses of the vaccine and placebo.
The RDIF, Russia’s sovereign wealth fund, said that there were “no unexpected adverse events during the trials” but added that some of those inoculated had short-term minor adverse effects such as flu-like symptoms.
40,000 volunteers are currently taking part in the double-bind, randomised Phase III clinical trial, half of whom have received two doses of the vaccine.
Sputnik V’s announcement follows reports by Pfizer/ BioNTech and Moderna showing the efficacy of their vaccines at approximately 95 per cent. Oxford University’s AstraZeneca showed a 70 percent efficacy.
The scientists and investors behind Sputnik V also boasted on Tuesday the two doses of the vaccine would cost under 20 US dollars, which would make it the cheapest Covid-19 vaccine on the market.
Unlike the Pfizer jab, the Russian vaccine can be stored at the fridge temperature, cutting the costs of storage and transportation.
Mikhail Murashko, Russia’s health minister, said in a statement released on Tuesday that “data demonstrating high efficacy of the Sputnik V vaccine give us hope that we will soon obtain the most important tool in the fight against the pandemic of the novel coronavirus infection”.
The Gamaleya Centre has yet to publish the full clinical report after Phase III clinical trials are completed. Russian vaccine developers previously frustrated the scientific community by making optimistic pronouncements before publishing full data on clinical trials.
Dr Vasily Vlassov, a public health expert at Moscow’s HSE University, described Sputnik V’s claim of the 95 per cent efficacy as “a typical example of data dredging when data are misused to showcase the desired result”.
The RDIF specified that the efficacy of the vaccine is calculated at “three statistically significant check points” – at 20, 39 and 70 cases of Covid-19 infections among volunteers who received the vaccine and the placebo. The 95 per cent efficacy of the immune response was achieved on the basis of 39 confirmed cases identified among the volunteers, the RDIF said.
The 39 cases of infections is too few to make far-reaching conclusions, Dr Vlassov told the Telegraph. Other scientists were more optimistic.
“Whilst the case numbers remain small, this is highly effective (91.4 per cent efficacy) with a lower confidence bound of approximately 80 per cent,” Prof Azra Ghani, Chair in Infectious Disease Epidemiology at Imperial College London, said in a statement.
“The lack of any serious adverse events in approximately 20,000 trial participants is also very encouraging. However, full details of the safety profiles for all four vaccines will need to be closely scrutinised by regulators in the coming weeks.”
Hungary became the first EU country last week to receive the Russian vaccine for testing, and other countries are likely to follow the suit. Sputnik V, according to Dr Vlassov, is likely to find enough buyers abroad as many countries would want to hedge their bets and not have to rely on one vaccine.