Russia’s Sputnik V coronavirus vaccine gives around 92% protection against Covid-19, late stage trial results published in The Lancet reveal.
It has also been deemed to be safe – and offer complete protection against hospitalisation and death.
The vaccine was initially met with some controversy after being rolled out before the final trial data had been released.
But scientists said its benefit has now been demonstrated.
It joins the ranks of proven vaccines alongside Pfizer, Oxford/AstraZeneca, Moderna and Janssen.
The Sputnik vaccine works in a similar way to the Oxford/AstraZeneca jab developed in the UK, and the Janssen vaccine developed in Belgium.
It uses a cold-type virus, engineered to be harmless, as a carrier to deliver a small fragment of the coronavirus to the body.
Safely exposing the body to part of the virus’s genetic code in this way allows it to recognise the threat and learn to fight it off, without risking becoming ill.
After being vaccinated, the body starts to produce antibodies specially tailored to the coronavirus.
This means the immune system is primed to fight coronavirus when if it encounters it for real.
It can be stored at temperatures of between 2 and 8C degrees (a standard fridge is roughly 3-5C degrees) making it easier to transport and store.
Different second dose
But unlike other similar vaccines, the Sputnik jab uses two slightly different versions of the vaccine for the first and second dose – given 21 days apart.
They both target the coronavirus’s distinctive “spike”, but use different vectors – the neutralised virus that carries the spike to the body.
The idea is that using two different formulas boosts the immune system even more than using the same version twice – and may give longer-lasting protection.
As well as proving effective, it was also safe with no serious reactions linked to the vaccine during the trial.
Some side effects to a vaccine are expected but these are usually mild, including a sore arm, tiredness and a bit of a temperature.
And there were no deaths or serious illness in the vaccinated group linked to the jab.