Researchers from Moscow-based Gamaleya institute, an offshoot of the Russian Ministry of Health, published detailed phase 1/2 results of their COVID-19 vaccine in the Lancet. If true (remember that we are talking about Russia), these results imply that their vaccine is both effective and has a tolerable safety profile which would make it a strong contender in the international race to defeat COVID-19.
While some moral and medical conventions were certainly skipped to get the vaccine across the finish line as first, there is no reason to believe that it could not become a viable tool to end the pandemic upon completion of ongoing phase 3 trials.
As mentioned previously, the vaccine Gam-COVID-Vac (aka Sputnik) uses a combination of two human adenoviruses rAd26-S and rAd5-S administered 21 days apart as vectors to train the immune system to detect and neutralize SARS-CoV-2. Trial results indicate that this method is effective at eliciting an immune response comparable to convalescent plasma and similar to what the other current frontrunner vaccines achieve. Interestingly and unlike its competitors, the study also describes encouraging data on CD4 and CD8 antibody responses, which are widely believed to be the key building lasting immunity.
While the safety profile is comparable to other vaccine candidates with mild to moderate side effects such as headache, fever and fatigue, the trial was conducted on only 76 relatively young (mean ~ 27 years) and based on the average weights rather skinny participants. As mentioned previously, the real challenge with vaccine trials lies in identifying and mitigating adverse side effects that affect only a small portion of the population.
Severe side effects that manifest in fewer than 0.1% of patients could still proof disastrous if entire countries are vaccinated. Also, it seems the Russian vaccine still needs to be tested on older populations as they are among the first in line to be vaccinated. Furthermore, the large scale correct administration of a vaccine with two different vectors remains an administrative and logistical challenge compared to vaccines with two identical shots.
Addendum: Meanwhile a group of researchers have published an open letter to the authors of the Gamelaya Institute study and the editor of the Lancet. They lament the unavailability of the data of study for peer review and highlight problematic similarities in unrelated data points in the study, suggesting that some data was either processed erroneously or manipulated outright.
Prognoses are no reliable indicator for future performance.