The vaccine, developed by the Gamaleya National Research Institute of Epidemiology and Microbiology, is based on a safe and tested human adenovirus vector platform
The world is gradually getting back on its feet after the long haul brought forth due to the coronavirus. However, the danger hasn’t lifted entirely.
While people around are getting vaccinated (some with the first dose and others fully vaccinated), news of new variants being recognised is also coming through. Several countries have imposed travel restrictions as World Health Organisation (WHO) designated a new coronavirus strain detected in South Africa as a “variant of concern”.
It is likely to take weeks to determine how effective current COVID-19 vaccines are against the variant.
This only goes to show that we need to continue being on high alert and get vaccinated, if not done yet. The news of new variant, on one hand raises concern but also reinstates belief in the power of vaccines.
Russia’s Sputnik V, world’s first registered vaccine based on a well-studied human adenoviral vector-based platform, was recently part of new studies to check on its efficacy. The vaccine, developed by the Gamaleya National Research Institute of Epidemiology and Microbiology, is based on a safe and tested human adenovirus vector platform.
Sputnik V is a two-vector vaccine against coronavirus. 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. Among the major COVID vaccines in development to date, only Gam-COVID-Vac uses this approach.
The technological platform of adenovirus-based vectors makes it easier and faster to create new vaccines through modifying the initial carrier vector with genetic material from new emerging viruses that helps to create new vaccines in relatively short time. Such vaccines provoke a strong response from a human immune system. Human adenoviruses are considered as some of the easiest to engineer in this way and therefore they have become very popular as vectors.
A unique independent nationwide observational study in EU member state Hungary estimating and directly comparing efficacy of five vaccines against COVID has demonstrated that the Russian Sputnik V vaccine has the highest (98 per cent) efficacy in preventing COVID-related mortality and 85.7 per cent efficacy against coronavirus infection leading alongside the vaccine by Moderna.
The Russian vaccine proved the best in protection against COVID related mortality and leads alongside the vaccine by Moderna in efficacy rate against COVID infection based on analysis of data from 820,000 individuals vaccinated with Sputnik V. The study has also demonstrated Sputnik V is 100 per cent effective against COVID related deaths in individuals aged 16-44 years.
Moreover, according to Ministry of Health of the Republic of San Marino on the Russian Sputnik V vaccine demonstrating it is 80 per cent effective against coronavirus infection from 6th to 8th months after administering the second dose. Efficacy of Sputnik V on 6-8 months is much higher than officially published efficacy of mRNA vaccines.
It can be established that adenoviral vaccines provide for longer efficacy than mRNA vaccines due to longer antibody and T-cell response. The data is based on the number of COVID infections in San Marino in November 2021. Efficacy was calculated based on data obtained from over 18,600 individuals fully vaccinated with Sputnik V not less than five months before November.
This clearly demonstrates that development stage of each vaccine is critical and more efforts are required for preventing any future strains from having the deadly impact that coronavirus has had in the recent past.
Dr Gajendra Singh is a public health expert. Dr Anuja Gupta is a microbiologist