After Russia broke the news of having developed the world’s ‘first coronavirus vaccine‘ with pomp, hope and questions shot up in equal measure among the public which has braced through 6 months of the pandemic. Now, the Russian Direct Investment Fund’s head Kirill Dmitriev has said that the clinical trials of the Sputnik-V Vaccine will be conducted in India this month, among other countries. The preliminary results of the Phase-III trial will be published in October-November this year.
The trials will be also be conducted in Saudi Arabia, United Arab Emirates (UAE), the Philippines, and Brazil. Russian President Vladimir Putin’s daughter has also been inoculated by the vaccine developed by the Gamaleya Center. While experts have continually issued caution against the vaccine which they say is yet to undergo all necessary trials and tests, Putin has assured against the same. To answer some of these questions and doubts, Russian state daily ‘Sputnik News’ has issued an FAQ on the much-awaited vaccine. Read more to know:
Question 1: Did you steal your vaccine?
No, we did not steal it. The vaccine uses a unique two-vector human adenovirus technology which no-one else in the world currently has for COVID-19. Vectors are engineered viruses, unable to reproduce, which carry genetic material from the spike of coronavirus. Our technology employs two different human adenoviral vectors, Ad5 and Ad26, for a first and a second injection. This technology helps to overcome pre-existing immunity to adenoviruses. Russia has benefitted from modifying for COVID-19 an existing two-vector vaccine platform developed in 2015 for Ebola fever, which went through all phases of clinical trials and was used to defeat the Ebola epidemic in Africa in 2017.
Admittedly, after some initial hype this question was dropped even by Russia’s most strident critics, because it had no grounds. But it is still important to highlight it since we saw attempts to paint the Russian vaccine in dark colors even before it was registered.
Question 2: When will the Phase 1 and 2 clinical trials results be published?
They were published on September 4 in The Lancet, one of the oldest and most respected medical publications in the world, after going through a thorough peer review process. This is just the beginning of a series of publications. The key points of The Lancet article are:
Phase 1-2 clinical trials of Sputnik V showed no serious adverse events (SAE, Grade 3) for any of the criteria, while the incidence of serious adverse events for other candidate vaccines ranged from 1 to 25 percent.
In 100 percent of participants in the clinical trials Sputnik V generated a stable humoral and cellular immune response. The level of virus-neutralizing antibodies of volunteers vaccinated with Sputnik V was 1.5 times higher than the level of antibodies of severe COVID-19 patients who had recovered from COVID-19. In contrast, British pharmaceutical company AstraZeneca demonstrated the level of antibodies of its volunteers under its clinical trial at a level virtually equal to the level of antibodies of those who had recovered from coronavirus. T-cell immunity with both types of CD4+ and CD8+ special cells was formed in all volunteers participating in clinical trials of the Sputnik V vaccine. These special cells recognize and disrupt the cells infected by SARS-CoV-2 and form the basis for long-term immunity.
Specialists from the Gamaleya National Research Center of Epidemiology and Microbiology managed to prove the effectiveness of the human adenoviral vectors platform, despite concerns that vaccinated people could have pre-existing immunity to human adenoviruses. The optimal safe dosage has been determined, which allows an effective immune response to be achieved in 100 percent of those vaccinated in trials, even in those who have recently had an adenovirus infection. Concern about the pre-existing immunity for adenoviral infections was the main reason for the emergence of alternative methods such as monkey adenoviral vector or mRNA platforms that have not been studied and tested over many years. The proven efficacy of Sputnik V reduces the need for hasty development of such platforms at the expense of safety.
Through the use of two different vectors – based on human adenovirus serotypes Ad5 and Ad26 – in two separate shots, it is possible to achieve a more effective immune response. Whereas in the case of using the same vector for two shots, the immune system launches defense mechanisms and begins to reject the drug in the second injection. Thus, the use of two different vectors in the Sputnik V vaccine avoids a possible neutralizing effect and provides for a stronger and more durable immune reaction.
Question 3: Were there too few participants in Phase 1-2 trials of Sputnik V?
On the surface the Sputnik V trial with 76 participants seems smaller in size compared to 1,077 people that, for example, AstraZeneca had in its Phase 1-2 studies. However, the design of the Sputnik V trial was much more efficient and based on better assumptions. AstraZeneca ran its trial from the beginning with a one-shot model but that was a false assumption since only a two-shot model can provide a long lasting immunity as AstraZeneca conceded following the trials. As a result of wrong initial assumptions, AstraZeneca tested the two-shot model only on 10 people out of 1,077. Overall, the number of people who received two injections in the Sputnik V trial exceeded the similar number in AstraZeneca trial by 4 times. Most media missed this point.
Question 4: Will there be clinical trials on more people?
The post-registration studies involving more than 40,000 people started in Russia on August 26, before AstraZeneca has started its Phase 3 trial in the U.S. with 30,000 participants. Clinical trials in Saudi Arabia, United Arab Emirates (UAE), the Philippines, India and Brazil will begin this month. The preliminary results of the Phase 3 trial will be published in October-November 2020.
Question 5: Why has the vaccine already become eligible for emergency use registration?
Because of the very positive results of the Phase 1-2 trials and because the human adenoviral vector-based delivery platform has been proven the safest vaccine delivery platform over decades including through 75 international scientific publications and in more than 250 clinical trials.
The scientists provided convincing data on safety of use of human adenoviral vaccines and medicines worldwide based on studies since 1953. According to records, more than 10 mln U.S. military personnel have received human adenoviral vaccines since 1971. A cancer treatment, Gendicine, based on human adenoviral vectors has been administered to more than 30,000 people in China in the course of 15 years. Clinical trials of vaccines based on human adenoviral vector technology using the same vectors as Sputnik V, have already involved more than 25,000 people worldwide. Since 2015 more than 3,000 people were administered human adenoviral vector-based vaccines against Ebola fever and Middle East Respiratory Syndrome (MERS) created in the Gamaleya Center.
So Russia registered the vaccine because it had a previously approved, a safe and efficient human adenovirus delivery platform for other illnesses. Since the registration of Sputnik V in Russia, other countries also announced plans to follow the Russian approach for emergency use registration of their vaccines. Sinovac Biotech’s vaccine received a similar approval in China. The government of the United Kingdom and the head of the U.S. Food and Drug Administration (FDA) Stephen Hahn have signaled potential for fast-track registration for British and American vaccine makers, respectively, despite their earlier reservations.
Question 6: Does anyone else use similar technology for their vaccines?
Some other companies are using human adenoviral vector-based platforms for their COVID-19 vaccines. For example, Johnson & Johnson uses only Ad26 vector and China’s CanSino only Ad5 while Sputnik V uses both of these vectors. The work of Johnson & Johnson and CanSino not only validates the Russian approach but also shows Sputnik V’s advantage as studies have demonstrated that two different vectors produce better results than one.
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