Sputnik V: Results showed 91.6% efficiency, as published by The Lancet

The Lancet published today on the interim results of the phase III study of the Sputnik V vaccine in nearly 20,000 people, information that provides the detailed data expected by everyone.

In the interim efficacy analysis of the randomized, double-blind, placebo-controlled clinical trial of 19,866 volunteers, 14,964 received the vaccine and 4,902 received the placebo. The two doses were administered 21 days apart and an efficiency of 91.6% was achieved. The calculation is based on the analysis of 78 identified confirmed cases of Covid-19: in the group that received the placebo, there were 62 cases, and in the group that received the vaccine, 16.

In the clinical trial, after the first week (when protection was not yet developed), 20 confirmed severe cases of Covid-19 were recorded in the placebo group and none in the vaccinated group. Over a period of 7 to 14 days, the effectiveness of the vaccine [para evitar casos graves] it increased to 50%, between 14 and 21 days, to 74.1% and from day 21, to 100%.

For people over 60, the study included 2,144 volunteers from this age group (with a maximum of 87 years), and also showed good safety results. Efficacy in the elderly was 91.8%, similar to that obtained in the 18-60 age group.

In the study, 70 episodes of serious adverse events unrelated to coronavirus in 68 participants: 45 were in the vaccinated group and 23 in the placebo group. “The side effects are few and they were double in the vaccine group, but considering that this group was three times larger, it is less than in those who received the placebo”, explains the Argentine molecular biologist residing in the States – United Ernesto Resnik.

According to an independent data monitoring committee, none were attributable to the vaccination. Most of the adverse events (94%) were mild and limited to flu-like symptoms, injection site reactions, headache, and asthenia (weakness, lack of energy).

Additional data

“The article published in The Lancet, one of the most important scientific journals, confirms the information previously presented and offers additional data on the efficacy and safety of this vaccine in different subgroups”, says Omar Sued, president of the Argentine Society of Infectious Diseases. and one of the two local experts who make up the independent international advisory committee assembled by the Gamaleya Institute. Three characteristics are worth highlighting: a good knowledge of the immunity generated by the vector, the two-dose strategy which should ensure long-term immunity, and the use of two different adenoviruses which could minimize the risk of an immune response against the first vector, which if it occurs could attenuate responses against Covid-19 “.

For Sued, from the point of view of the public, it is important to note that the efficacy of the vaccine was very high already two weeks after the first injection, which justifies the design of single-dose studies. “The vaccine was effective in all subgroups of participants, including those over 60 years of age and there were no severe cases of Covid among those vaccinated (100% effectiveness) – adds he -. The safety profile was very good as it did not exhibit serious adverse events related to vaccination. Based on these good results and the need to expand its use to the whole population, new studies should be urgently designed to assess the efficacy of this vaccine in other populations, such as people living with HIV, immunocompromised children and adolescents, and pregnant women, while its effectiveness is continuously monitored in areas where new variants of SARS-CoV-2 are prevalent. “

“The number of events analyzed (78) is lower than that of Pfizer and Moderna, but they are well within the limits of acceptance,” says Resnik. For reference, Novavax [de Janssen] presented its data last week with only 62. In contrast, the vaccine generated an immune response greater than the typical immunity of convalescent serum (between 1.3 and 1.5 times higher), which is consistent with this. than other vaccines show. “

“The vaccine is 100% effective in preventing serious illness or death, which is ultimately the most crucial parameter; we can all cope with sneezing as long as we stay out of the hospital or cemetery. Even after a single dose of the booster regimen, protection against disease was 87.6%. Therefore, Sputnik V will be of great value in the fight against the global COVID-19 pandemic, ”acknowledges Hildegund CJ Ertl., Center for Vaccines and Immunotherapy, The Wistar Institute, USA.

In search of a more lasting effect, the Sputnik V vaccine uses two well-known human adenoviruses (Ad5 and Ad26, one in each dose) and genetically modified so that they cannot reproduce in the body. They are the vehicle that transports protein S from the outer part of the coronavirus to cells and arouses the body’s immune response.

World battle

In a statement released by the Gamaleya Institute, its director, Alexander Gintsburg, director of the Gamaleya Center for Epidemiology and Microbiology, said this formula generates a strong humoral and cellular immune response. “The publication of the internationally peer-reviewed data with the results of the Sputnik V clinical trials is a great achievement in the global battle against the COVID-19 pandemic,” he said. “The safety and high efficacy of the Russian vaccine is demonstrated by the solid scientific data presented. Several vaccines based on human adenoviruses have already been developed and this tool is one of the most promising for the development of new vaccines in the ‘to come up. “

Kirill Dmitriev, Executive Director of the Russian Fund for Direct Investment, commented: “This is a great day in the fight against the pandemic. According to independent peer-reviewed data published by The Lancet, Sputnik V fully protects against serious images of Covid-19, it is one of the three vaccines in the world with an efficiency greater than 90%, but it surpasses the latter in terms of safety, ease of transport, since it can be stored at a temperature of 2-8 degrees Celsius, and it’s affordable. “

In a comment published in the same issue of the scientific journal, Ian Jones and Polly Roy, who have no connection with the Gamaleya Center or the Russian Direct Investment Fund, say: “The development of the Sputnik V vaccine has been criticized due to haste, shortcuts and lack of transparency. But the reported results are clear. The principle of vaccination is being demonstrated and it means that another vaccine can join the fight to reduce the incidence of Covid- 19 “.

Sputnik V is already registered in 16 countries and this number is expected to increase to 25. In addition to Russia, it is produced in India, Korea and Brazil. Production will also begin shortly in China and in several countries more interested in joining; among them, Argentina.

With this, four vaccines have published phase 3 studies. The others are those from Pfizer / BioNtech, Astra Zeneca and Moderna.