According to an article published in The Lancet journal, Sputnik V, the world’s first registered coronavirus vaccine, approved by Russia last month, has been shown to elicit antibody response with no serious adverse events in small human trials.
The publication of the article carrying preliminary results of the Phase I-II clinical trials of the vaccine was announced by the Russian Direct Investment Fund (RDIF), Russia’s sovereign wealth fund, and the Gamaleya National Research Center of Epidemiology and Microbiology of the Ministry of Health of the Russian Federation.
Results from early-phase non-randomized vaccine trials in a total of 76 people show that two formulations of the vaccine have a good safety profile detected over 42 days, and induce antibody responses in all participants within 21 days.
Secondary outcomes from the trial suggest the vaccines also produce a T cell response within 28 days, the researchers said.
The findings are based on two small phase trials lasting 42 days — one studying a frozen formulation of the vaccine, and another involving a lyophilized (freeze-dried) formulation of the vaccine, they said.
The two-part vaccine includes recombinant human adenovirus type 26 (rAd26-S) and recombinant human adenovirus type 5 (rAd5-S), which have been modified to express the SARS-CoV-2 spike protein.
The trials took place in two hospitals in Russia, and were open-label and non-randomized, meaning that participants knew that they were receiving the vaccine and were not assigned by chance to different treatment groups.
The trials involved healthy adults aged 18-60 years, who self-isolated as soon as they were registered, and remained in hospital for the first 28 days of the trial from when they were first vaccinated.
The most common adverse events were pain at the injection site, hyperthermia, headache, asthenia (weakness or lack of energy), and muscle and joint pain.
The authors note that these adverse effects are also seen with other vaccines, particularly those based on recombinant viral vectors.