A preliminary trial of Russia’s Sputnik V COVID-19 vaccine suggests that a two-dose regimen of the vaccine offers 91.6% efficacy against symptomatic COVID-19, according to findings published on Tuesday (2 February). At the same time, the European Commission confirmed it does not rule out a deal for the vaccine.
The preliminary findings, published in The Lancet, are based on an analysis of Phase 3 trial data from nearly 20,000 participants, three-quarters of whom received the vaccine and one-quarter received a placebo.
It found that the vaccine induced an antibody and cellular immune response with data from 342 and 44 participants, respectively.
No serious adverse events were deemed to be associated with vaccination, and most reported adverse events were mild, including flu-like symptoms, pain at the injection site and weakness or low energy.
A sub-analysis of 2,000 adults older than 60 years suggests the vaccine was similarly effective and well-tolerated in this age group.
“Our interim analysis of the randomised, controlled, phase 3 trial of Gam-COVID-Vac in Russia has shown high efficacy, immunogenicity, and a good tolerability profile in participants aged 18 years or older,” Inna V Dolzhikova, co-lead author, Gamaleya national research centre for epidemiology and microbiology in Russia, said.
Addressing the criticism surrounding the vaccine, concerning “unseemly haste, corner-cutting, and an absence of transparency,” Professor Ian Jones of the University of Reading, and Professor Polly Roy of the London school of hygiene and tropical medicine, said in a joint statement that the outcome reported by the Lancet is “clear” and the “scientific principle of vaccination is demonstrated”.
This means “another vaccine can now join the fight to reduce the incidence of COVID-19,” the statement added.
EU looking to ‘diversify vaccine portfolio’
Asked about the increased interest in the Russian vaccine and the possibility of its approval in the EU, Stefan de Keersmaecker, the European Commission spokesperson for public health and food safety, did not rule out the possibility of striking a deal for the vaccine.
Instead, he highlighted that the priority of the Commission is to ensure a “diversified, broad portfolio,” adding that there is “absolutely no nationalism” involved in deciding which companies to enter into an advanced purchase agreement with.
“It is not a matter of having only certain nationalities of companies, absolutely not,” he said, adding that the EU Commission welcomes all initiatives that lead to building production capacity.
Instead, the main consideration is that companies comply with the criteria set out in the EU’s vaccine strategy.
As well as a positive assessment from the European medicines agency (EMA), this also includes ensuring an EU-based production capacity, he stressed, pointing out that this is necessary to ensure that vaccines are ready to go the moment the vaccine gets the green light.
The decision as to whether or not to enter into an advanced purchase agreement with a company rests on this ability to ensure EU based production capacity, he reiterated.
More work must now be done to assess the vaccine, including an investigation as to the full duration of protection and the inclusion of wider diversity of participants, given that most of the participants in the trial were white, and not all risk groups were represented by the study, including adolescents and children, as well as pregnant women.
The authors also note that because COVID-19 cases were detected only when participants self-reported symptoms (followed by a PCR test), the efficacy analysis only includes symptomatic cases of COVID-19, and further research is needed to understand the efficacy of the vaccine on asymptomatic COVID-19, and transmission.
The trial is currently ongoing and aims to include a total of 40,000 participants.
[Edited by Zoran Radosavljevic]