Controversy surrounding the Sputnik V vaccine.

The Sputnik V COVID-19 vaccine is a member of the so-called vector vaccines and uses two different vectors (Ad26 priming and Ad5 boost) to reduce the risk of a reduction in the effectiveness of the vaccination. Real life data indicate an efficacy of the vaccine above 97%. Low cost and no need for ultra-cold storage temperature temperatures are other pluses of the Sputnik V vaccine. However, there are also several important shortcomings that must be considered such as the possible reduction of its immunogenicity in the presence of very high Ad5 neutralizing antibody titres and the decrease with age of the antibody titres neutralizing the virus. Furthermore, there is emerging documentation that Sputnik V has a reduced neutralizing capacity against the Beta variant and all variants with the spike protein carrying the E484K substitution. Nevertheless, due to its characteristics, Sputnik V could be another useful means of satisfying the need for mass vaccination. However, it is imperative to document the efficacy and safety of the Sputnik V vaccine in individuals with high pre-existing anti-Ad26 and Ad5-neutralizing antibody titres and in those under the age of 18 or older than 60 years and be certain that Sputnik V does not cause the rare development of immune thrombotic thrombocytopenia. It is hoped that the now widespread use of this vaccine will generate a large pragmatic real-world study with data accessible to anyone interested in verifying them.