Preliminary Phase 3 Trial Results of the Russian COVID-19 Vaccine Sputnik V

The COVID-19 pandemic, caused by the coronavirus SARS-CoV-2, is an ongoing global disruption. Large amounts of effective vaccines are urgently needed to fight the pandemic. The “Sputnik V” COVID-19 vaccine, also called Gam-COVID-Vac, was developed by the Gamaleya Research Institute of Epidemiology and Microbiology, Moscow, Russia. It is an adenovirus viral vector vaccine. The vaccine was approved for distribution in Russia as early as August 2020 on the basis of preliminary results of phase 1/2 studies. This approval in the absence of robust phase 3 trial results was controversial.

Denis Y. Logunov, Gamaleya Research Institute of Epidemiology and Microbiology, and colleagues have reported preliminary results on the efficacy and safety of Sputnik V based on an interim analysis of a phase 3 trial. The trial is a randomized, double-blind, placebo-controlled phase 3 trial at 25 hospitals and polyclinics in Moscow, Russia. It has 21,977 adult participants, of which 16,501 were randomly assigned to the vaccine group and 5,476 to the placebo group. 19,866 Participants have already received two doses of the vaccine or the placebo and were included in the preliminary analysis.

The team found that starting 21 days after the first dose of the vaccine, the vaccine efficacy is 91.6 %. This is based on 16 of 14,964 (0.1 %) participants in the vaccine group which were confirmed to have COVID-19, versus 62 of 4,902 (1.3 %) in the placebo group. The vaccine was also deemed safe on the basis of the preliminary results. The researchers recorded no serious side effects that were considered related to the vaccine. Serious adverse events unrelated to the vaccine were reported in 45 and 23 participants from the vaccine group and placebo group, respectively. Four deaths were reported during the study (three of those in the vaccine group), but they occurred in participants with serious preexisting health conditions, and none of the fatalities were considered related to the vaccine.

Safety and efficacy of an rAd26 and rAd5 vector-based heterologous prime-boost COVID-19 vaccine: an interim analysis of a randomised controlled phase 3 trial in Russia,
Denis Y. Logunov, Inna V. Dolzhikova, Dmitry V. Shcheblyakov, Amir I. Tukhvatulin, Olga V. Zubkova, Alina S. Dzharullaeva, Anna V. Kovyrshina, Nadezhda L. Lubenets, Daria M. Grousova, Alina S. Erokhova, Andrei G. Botikov, Fatima M. Izhaeva, Olga Popova, Tatiana A. Ozharovskaya, Ilias B. Esmagambetov, Irina A. Favorskaya, Denis .I Zrelkin, Daria V. Voronina, Dmitry N. Shcherbinin, Alexander S. Semikhin, Yana V. Simakova, Elizaveta A. Tokarskaya, Daria A. Egorova, Maksim M. Shmarov, Natalia A. Nikitenko, Vladimir A. Gushchin, Elena A. Smolyarchuk, Sergey K. Zyryanov, Sergei V. Borisevich, Boris S. Naroditsky, Alexander L. Gintsburg, the Gam-COVID-Vac Vaccine Trial Group,
Lancet 2021.
https://doi.org/10.1016/S0140-6736(21)00234-8

Also of Interest