The prestigious scientific journal Lancet has published the results of the third phase of clinical trials of the Russian vaccine “Sputnik V”, developed by the Gamaleya Research Center. According to preliminary data, the effectiveness of the vaccine against SARS-CoV-2 infection was 91.6%. As the scientists emphasize, the same effectiveness was observed in the group of people over 60 years of age. As stated at the briefing dedicated to the publication, Alexander Gintsburg, the director of the Gamaleya Center, said that scientists have concluded that immunity after the “Sputnik” vaccine can last “at least two years or more”. According to Kirill Dmitriev, head of RDIF, the vaccine is effective against new strains of coronavirus detected in the United Kingdom and South Africa. According to researchers, “Sputnik” provides “100% protection” against moderate and severe cases of Covid-19.
During the study, there were several deaths among volunteers, but they were not related to the vaccine, according to the Lancet article. According to preliminary research conducted on 20,000 people, the vaccine demonstrated an efficacy rate of 91.6% against Covid-19. In a group of 14,964 volunteers who received a shot of the actual vaccine, only 16 people, or 0.1% of those who received the drug, got sick. In the placebo group, which included 4,902 people, 62 people, or 1.3% of those who received saline, became ill. This number of cases was recorded 21 days after the first dose of the drug. PCR testing for coronavirus was performed on subjects during the initial screening and prior to administration of the second dose, as noted in the article. Testing was also performed when participants reported symptoms of acute respiratory viral infection. The small number of participants in the placebo group is explained by an ethical dilemma that poses difficulties for the placebo group during the pandemic – researchers stop recruiting for this group once civilian vaccination has begun. Many study participants, “waking up” with an antibody test, voluntarily withdraw from the study. The Russian service of the BBC wrote about this in detail here.
As part of the secondary analysis, the authors distinguished the study of the efficacy of a vaccine against moderate or severe cases of Covid-19. It is reported that after 21 days from the first dose, no cases of moderate or severe disease were observed in the vaccinated group, while 20 cases were observed in the placebo group, which corresponds to 100% efficacy against moderate or severe disease. According to the study, the vaccine induced not only a humoral immune response (antibodies appeared), but also a cellular immune response – this is confirmed by data from 342 (vaccine) and 44 (placebo) participants, as stated in the study. Six of the 342 participants did not develop an immune response after vaccination, possibly due to older age or individual characteristics, as noted in the Lancet article. Serious adverse events requiring hospitalization were rare in both groups of volunteers – in the placebo group (0.4%) and in the vaccine group (0.2%). The article emphasizes that no serious case was associated with vaccination. Four study participants died (three in the vaccine group, one in the placebo group) – but none of these deaths were directly related to the administration of the drug, according to the Lancet article.
The study involved 2144 people over the age of 60, in this group the vaccine showed an efficacy rate of 91.8%. The most common adverse events were flu-like symptoms and local reactions. There were also three serious adverse events in the placebo group (urinary tract stones, sinusitis, and influenza-like illness) and three in the vaccine group (renal colic, deep vein thrombosis, and limb abscess). The study found no association between the adverse events and the vaccine. “To stop the Covid-19 pandemic, it is necessary to introduce different vaccines based on different mechanisms of action to meet different global health needs. Our vaccine, together with other vaccines against SARS-CoV-2, helps to diversify the range of vaccines against SARS-CoV-2,” the journal quoted Denis Logunov, deputy director of the Gamaleya Center and one of the authors of the study, as saying. The authors note that because cases of disease were only detected when participants self-reported symptoms, the efficacy analysis only includes the disease with its symptomatic manifestation, and further research is needed to understand the vaccine’s efficacy with respect to asymptomatic Covid-19 and its transmission. The average observation period for participants was 48 days from the first dose, so the study cannot assess the full duration of protection as stated in the article. Although the study format does not allow the effectiveness of a single vaccination to be assessed, the results suggest that partial protection begins as early as 16-18 days after the first vaccination, according to the study. From day 15 to day 21, efficacy against moderate or severe disease was 73.6%, but more research is needed to draw reliable conclusions from these observations. “Adenoviral vector vaccines have been used before, and their safety has been confirmed in several clinical trials,” the article states.
In September, the Lancet published the results of the second phase of Sputnik’s safety studies. Following this publication, an international group of scientists contacted the journal requesting more detailed information on the results of the clinical trials. However, they were not provided with this data. The scientists’ suspicions were aroused by surprising and unlikely coincidences of indicators in different test groups. Scientists also noted the speed of publication and the confusion of dates. The tests were completed only on August 10, and to prepare and print such a study in three weeks is almost unbelievable. Scientists expressed their concerns in an open letter to the Lancet, demanding that the full clinical trial protocol for the “Sputnik” vaccine be made available to the public. However, the response to this request did not satisfy the critics and only intensified their cautious attitude towards the research. “[The authors of the Russian article] did not provide any data,” said Enrico Bucci, a professor of biology at Temple University in the United States and a well-known crusader against pseudoscience, in a statement to the BBC. “We have not even been given access to the original research data.” “The response to our questions was formal, we never saw the actual data,” said Konstantin Andreev, a doctoral student at Northwestern University in the US, in an interview with the BBC. Andreev also signed the appeal to the Lancet. In the Lancet, they then refused to disclose any details of the Russian scientists’ preparation of the article for publication. The scientific community found the new Lancet article more convincing. According to Professor Enrico Bucci, there are no questions about the safety of the Russian vaccine, only doubts about its claimed effectiveness. However, these doubts cannot be confirmed or refuted in the absence of “raw” data from the research conducted. The developers of Sputnik once again did not provide them, citing confidentiality and the need for prior approval of any requests with the authors of the article. “So, in fact, the initial data are available only to ‘their own,'” explains candidate in biological sciences Nikita Khromov-Borisov, who is a member of the Russian Academy of Sciences’ Commission on Combating Pseudoscience and Falsification of Scientific Research. “And these games of secrecy raise unnecessary suspicions.” According to other experts, there are other minor flaws in the article published by Russian developers, but they indicate that the work was hastily written and edited, rather than the quality of the study itself.