Russia’s “Sputnik V” COVID Vaccine Makes Strong 91.6 % Efficacy Showing In Peer-Reviewed Trial Results   
Sputnik V is 91.6% effective against symptomatic COVID-19 and 100% effective against moderate and severe disease

Fulfilling the legacy of its pioneering name, the Russian Sputnik V vaccine, was over 91% effective in preventing symptomatic COVID-19 cases and 100% effective in preventing severe COVID, according to results published Tuesday in The Lancet

Globally, that means that the Sputnik vaccine joins the club with just two other coronavirus vaccines that have demonstrated an efficacy of 90% or more – the others being Moderna’s and Pfizer’s high-tech mRNA vaccines.  

The Lancet publication also marks the first time that Phase 3 trial results of one of the “elusive trio” of Russian and Chinese vaccines have been published in a peer-reviewed journal.  That marks a big step forward in the transparent review of vaccines generally – setting a bar that Chinese vaccines will have to pass over as well to gain WHO approval and widespread public acceptance.  

Good News for Low and Middle Income Countries 

Most importantly, the results are very good news for the nearly fifty countries across the globe that have pre-ordered over 1.2 billion doses of the Sputnik vaccine, developed by Russia’s Gamaleya National Research Institute of Epidemiology and Microbiology, and marketed abroad by the Russian Direct Investment Fund (RDIF). 

Even before Sputnik’s Phase 3 results were formally published, the vaccine had been administered to about 2 million people worldwide thanks to an aggressive  Russian marketing campaign. 

Its low price of $US 10 per dose, and easy storage in conventional refrigerators at temperatures of 2°C to °8 C, has indeed made Sputnik a strong market competitor with the vaccines being produced by pharma companies in western Europe and the United States. Although at US$ 3 a dose, the AstraZeneca/Oxford vaccine produced by the Swedish-British collaboration is even more affordable – thanks to AstraZeneca’s no-profit pledge.

Kirill Dmitriev, head of the RDIF

The landmark publication of results in a prestigious peer-reviewed journal now means that Sputnik skeptics have “run out of arguments,” boasted Kirill Dmitriev, the head of the RDIF in a press briefing that coincided with the  announcement of the results: 

“When we take safety, efficacy, logistics, price, and long lasting immunity into account, certainly Sputnik is a leading vaccine in the world, and the publication The Lancet journal confirms that.”  

“Our interim analysis of the randomised, controlled, phase 3 trial of Gam-COVID-Vac [Sputnik] in Russia has shown high efficacy, immunogenicity, and a good tolerability profile in participants aged 18 years or older,” added Gamaleya’s Inna V Dolzhikova, a co-author of The Lancet’s Study, in a press release.

Trial Reports on 22,000 Participants 

The publication reported interim results from Russia’s randomised, double-blind, placebo-controlled, phase 3 trial in almost 22,000 participants, of which 75% received the vaccine and 25% received a placebo. 

The interim analysis found that only 16 out of 14,964 (0.1%) participants that received the vaccine developed symptomatic COVID-19, compared to 62 out of 4902 (1.3%) in the placebo group, demonstrating an overall efficacy of 91.6%. 

Importantly, secondary analyses found that the vaccine was 100% effective against moderate or severe COVID-19, and equally efficacious across all age groups, including older adults.

Apart from stimulating robust antibody responses in virtually all participants, Sputnik V also induced vigorous T-cell responses, an important component of immunity. In fact, only six of 342 participants in the vaccine group failed to develop antibodies, probably because they were older or due to possible immune disorders.

The findings also hint that a single dose of Sputnik could confer a partial protective effect of 75% within two weeks.

Although this would require further trials to confirm, the findings have already stimulated a joint trial that aims to employ Sputnik to boost AstraZeneca’s vaccine, as well as another Chinese vaccine.

We are ready to partner with the developers of vaccines having efficacy less than 90% to help them boost efficacy,” said Dmitriev on Tuesday. “We are about to launch clinical trials together with AstraZeneca in order to analyze how adding Sputnik components can increase the efficacy of the AstraZeneca vaccine, and we’re about to announce cooperation with another Chinese developer.”

Lack of Variant Analysis & Self-Reports Of COVID Cases Remain Key Limitations 

However, the study was not without limitations.  

Because COVID-19 cases were detected through participant self-reports, asymptomatic cases were excluded from the efficacy analysis, even though these account for at least one in five infections worldwide.

And unlike the Novavax vaccine candidate, which had almost the same levels of efficacy, the Sputnik trial results do not consider the new virus variants that have emerged recently, although these studies are ongoing, said Dmitriev.

“We’ve been doing analysis of variants that we’re seeing at the moment…But of course, is very important to continue analysis,” he said, noting that Sputnik may be better at outwitting variants than other vaccines.

In the case of the Novavax Phase 3 trials, released on Monday, the vaccine showed an overall efficacy of 95.6% against older virus variants, but dipped to 85.6% and 60% for British and South African variants respectively.  

If a similar analysis had been performed on Sputnik, it would be likely that the results of the vaccine’s potency against the variants would be lower – insofar as all of the vaccines currently in R&D were designed to fight a SARS-COV-2 variant that was prevalent up until the end of 2020. 

Based on a pre-existing Ebola vaccine developed about six years ago, Sputnik’s vaccine technology relies on two genetically modified human cold viruses, Adenovirus 26 and Adenovirus 5. AstraZeneca’s technology is also based on a deactivated adenovirus – but one that circulates exclusively in monkeys. 

Lancet Commentary Welcomes Results

Despite the shortcomings, the tone of a Lancet commentary, linked to the report of the trial results themselves, was congratulatory. 

“The development of the Sputnik V vaccine has been criticised for unseemly haste, corner cutting, and an absence of transparency,” said the commentary  by Polly Roy and Ian Jones from the London School of Hygiene & Tropical Medicine and and the University of Reading.  “But the outcome reported here is clear and the scientific principle of vaccination is demonstrated, which means another vaccine can now join the fight to reduce the incidence of COVID-19.”

On the other hand, the commentators noted that the vaccines from Pfizer and Moderna vaccines will retain an advantage in terms of the smaller volumes of the vaccine required per dose – even if their cold chain requirements are more rigid and their price is twice that of Sputnik, at about $20 per dose .

Vaccines based on adenoviruses – including not only Sputnik but also AstraZeneca – demand larger volumes of product – making their manufacture and transport bulkier across the supply chain. 

Sputnik’s Vaccine Production & Distribution Already Widespread 

Healthcare worker prepares Sputnik V vials

Sputnik’s vaccine has received considerable worldwide attention in recent months, with 16 countries across Latin America, Asia, Africa, including the United Arab Emirates and the Palestinian Authority in the Eastern Mediterranean Region, already having given the vaccine regulatory approval.  

Local production has begun in India, South Korea, Brazil, China, is set to begin in Kazakhstan and Belarus, probably also in Turkey, and maybe even in Iran, said Dmitriev.

In particular, India will be a “key partner” of Sputnik because of its massive manufacturing capacity, with potential to produce as much of the vaccine as Russia is producing now. 

“We’re even ready to call Sputnik V a Russian/Indian vaccine because we have five production partners in India, and from the very beginning we’ve been in very close collaboration, because India has outstanding production capacities for the vaccine,” said Dmitriev, whose comments also reflect the geopolitical alliances around vaccine collaborations.  

Vaccine Well Tolerated Across Ages – But Gender and Ethnic Diversity Was Lacking  

The vaccine was well tolerated in all age groups, including older adults, as well as people with underlying conditions, who made up a quarter of total participants in the trial. These included people with diabetes, hypertension, ischaemic heart disease and obesity.

Like most clinical trials, however, it lacked diversity – as two thirds of participants were male and almost all were white. So further research will also be needed in adolescents, children, pregnant and lactating women as well as other diverse populations, 

Fortunately, 94% of adverse effects were categorized as mild, and the severe adverse effects that occurred were considered to be unrelated with vaccination by the study authors as well as an independent data monitoring committee. In total, 45 participants in the vaccine group and 23 in the placebo group reported serious adverse events.

Although four deaths were recorded in the trial, of which three were in the vaccine group and one in the placebo group, none were related to the vaccine, said the study authors. 

In the vaccine group, one death was associated with a fracture and the remaining two were in people with pre-existing conditions that likely had developed COVID-19 symptoms before the trial began, said the study. Furthermore, both participants self-administered non-steroidal anti-inflammatory drugs without informing clinicians, which interfered with diagnosis and prompt medical help. In the placebo group, the death was associated with a stroke. 

Unclear How Long Immunity Will Last 

Like other vaccines, it’s unclear how long immunity against SARS-CoV-2 will last, but Sputnik’s vaccine-makers have “high hopes” that it could last for “at least two years”, said Alexander Ginstsburg, who leads the Gamaleya Institute.

“We have very high hopes that the immunity lasting after this vaccine would be lost for more than several months, even more than a year, but at least two years and probably even longer.”

Even if antibody levels decrease within several months, the immune response can easily be boosted with an additional shot, noted Gamaleya’s Denis Logunov, who co-authored the article.

“Stopping the COVID-19 pandemic requires the introduction of different vaccines based on different mechanisms of action to cover diverse global health demands. Our vaccine, along with other SARS-CoV-2 vaccines, helps to diversify the world SARS-CoV-2 vaccine pipeline,” he said.  

Image Credits: RDIF.

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