Sputnik V Bests Pfizer Jab in Effectiveness Against Omicron, Research Shows

Previous data already suggested that Sputnik V vaccine is highly effective against the Omicron variant, with studies also pointing at a lesser and slower decline of antibody levels for the Russian jab when compared to other vaccines.

Sputnik V is twice as effective as the Pfizer vaccine in neutralising the Omicron strain - this is the key takeaway from the latest analysis by Italy's National Institute for Infectious Diseases Lazzaro Spallanzani, Russia’s Gamaleya Research Centre for Epidemiology and Microbiology and Moscow State Sechenov Medical University.

The researchers pitted Russia’s Sputnik V vaccine against the Pfizer-BioNTech mRNA jab in a comparative preprint study published by MedRxiv portal. The goal was to explore the efficacy of the two COVID-19 vaccines against the Omicron variant.

The examination has been prepared by the 12 Italian scientists in a Rome lab, using the blood serum samples of persons vaccinated with these jabs, who had similar levels of IgG (immunoglobulin G) antibodies and the same neutralising activity against the initial variant of novel coronavirus registered in Wuhan.

It turns out that in comparison with the Pfizer jab, Sputnik V had 2.1 times more neutralising antibodies against the Omicron in general, and 2.6 times more antibodies three months after vaccination.

Neutralising antibody titres of the SARS-CoV-2 Omicron variant

© Sputnik

When it comes to in-depth analysis of protection mechanisms, researchers noted that Sputnik V neutralises the Omicron variant because it forms a stronger immune response due to the high level of antibodies. When reviewing the basic level of RBD (receptor-binding domain)-specific IgG antibodies, researchers pointed out that within the upper 25% of samples with the highest levels of IgG, 100% of individuals vaccinated with Sputnik V had these antibodies, compared to 83.3% in the Pfizer group. In total 74.2% of Sputnik V blood serum samples successfully neutralised the Omicron strain compared to 56.9% for Pfizer.

Percentage of blood serum samples with the identified level of virus-neutralising antibodies

© Sputnik

As to reasons why Sputnik V forms such an immense response to Omicron, there are several factors at play, such as producing a much broader spectre of neutralising antibodies, whilst the Pfizer jab uses the S-protein in proline-stabilised form aimed against specific parts of the antigen molecules, which, in the case of the Omicron are usually deformed by the virus’s mutations. Sputnik V’s heterologous prime boost technology also plays a role, with the Russian vaccine using two different carrier adenovirus vectors, with the human adenoviral vector platform itself having an additional advantage of being a better imitation of the infection. The Spallanzani-Gamaleya MedRxiv publication mentions this approach as the most effective one:

“Today the necessity of third booster vaccination is obvious. And the most effective approach, already shown in several studies, is the use of heterologous booster vaccination pioneered in COVID-19 vaccines by Sputnik V.”

The joint Italo-Russian study also confirms earlier findings by the Gamaleya Institute, which were published by MedRxiv in December of 2021. According to the document, Sputnik V has a high level of virus-neutralising activity against the Omicron variant.

The Universal Booster Shot

The overwhelming spread of the Delta variant followed immediately by the wave of the Omicron strain, has led to a global search for the perfect booster vaccine. The answer, according to the Russian Direct Investment Fund (RDIF), comes in the form of Sputnik Light.

Sputnik Light is single-shot vaccine based on the human adenovirus serotype 26 (which is also used as the first component of the two-dose Sputnik V). The Russian Ministry of Health recommends Sputnik Light as a booster to be applied 6 months after primary vaccination.

Data from clinical studies in Argentina and other countries, as well as from domestic trials, have shown high safety and immunogenicity of Sputnik Light as a booster shot for vaccines of other manufacturers. Its efficacy as a single-shot booster against the notorious Delta variant for other vaccines is close to the efficacy against Delta of the two-shot Sputnik V jab: more than 83% against infection and 94% against hospitalisation, as per a report by RDIF.

RDIF CEO Kirill Dmitriev has underlined the importance of using Sputnik Light as a booster:

“The adenoviral vector platform has already shown high efficacy in combatting coronavirus mutations in the past. Mix-and-match boosting with the use of Sputnik Light could raise the effectiveness of other vaccines, and partnership between various vaccine platforms plays a key role in light of challenges created by the simultaneous presence of Delta and Omicron variants.”

World’s First Registered Jab Against COVID-19

Sputnik V has been authorised for use in 71 countries with a total population of 4 billion people, with Australia becoming the latest nation to recognise the Russian vaccine. Sputnik Light has been authorised in 30 countries. Both jabs have been developed using a well-known adenovirus vector technology which as a 30-year-long history and a proven safety and efficacy record. Unlike the competing technology, the adenoviral virus platform has not been connected with serious adverse effects, such as pericarditis or myocarditis. Among other key advantages of Sputnik V is the fact that it can be kept at temperatures from +2 to +8 Celsius, which makes it easier to deliver and preserve the batches, while some of the competing vaccines require special ultra-low temperature freezers.

Russian Direct Investment Fund (RDIF) is the country's sovereign wealth fund, established to make equity co-investments, primarily in Russia, alongside international strategic and financial investors. The Fund is in charge of Sputnik V and Sputnik Light’s production and international distribution.

The Omicron variant of SARS-Cov-2 was identified in November 2021 and has rapidly become the dominant type of the novel coronavirus around the world. As of 12 January 2022, the Omicron strain has been registered in 150 countries.