Remite: Ruben Piacentini
Denis Logunov and colleagues1 report their interim results from a phase 3 trial of the Sputnik V COVID-19 vaccine in The Lancet. The trial results show a consistent strong protective effect across all participant age groups. Also known as Gam-COVID-Vac, the vaccine uses a heterologous recombinant adenovirus approach using adenovirus 26 (Ad26) and adenovirus 5 (Ad5) as vectors for the expression of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein. The use of two varying serotypes, which are given 21 days apart, is intended to overcome any pre-existing adenovirus immunity in the population.2 Among the major COVID vaccines in development to date, only Gam-COVID-Vac uses this approach; others, such as the Oxford–AstraZeneca vaccine, use the same material for both doses. The earlier vaccine for Ebola virus disease, also developed at Gamaleya National Research Centre for Epidemiology and Microbiology (Moscow, Russia), was similar, with Ad5 and vesicular stomatitis virus as the carrier viruses,3 and the general principle of prime boost with two different vectors has been widely used experimentally.