By Marcus Tan, Edited by Sami Morse
The Sputnik-V vaccine emerged on the world stage following Russian President Vladimir Putin’s announcement on August 11 that it had been approved for public distribution, making it the world’s first officially approved coronavirus vaccine. While these claims have since been walked back, pending results of their phase 3 clinical trials, vaccine development has been progressing efficiently. Sputnik-V is being developed by the Gamaleya National Research Institute of Epidemiology and Microbiology based in Moscow, with funding from the Russian Direct Investment Fund. This vaccine is an adenovirus-based viral vector, using an attenuated version of the virus responsible for the common cold to deliver SARS-CoV-2 proteins to patients in order to induce protection from the virus. The vaccine is administered in two doses and consists of two serotypes of the adenovirus, each with a Spike protein, responsible for the crown-like appearance that gives coronaviruses their name.
Sputnik-V completed Phase 1 and 2 trials on August 3 with the results of the first clinical studies being released on September 4 in The Lancet medical journal. Phase 1 and 2 trials were conducted between June 18 and August 3. In both trials, the vaccine was evaluated with 38 participants, each participant being a healthy adult aged 18-60 years. Participants were given one of two vaccine formulations differing only in the type of adenovirus used as a vector. The primary findings reported were that “both vaccine formulations were safe and well tolerated.” Most adverse side effects were mild with common symptoms being pain around the injection site and hyperthermia, abnormally high body temperature. Antibodies were produced in all participants. Experts and other immunologists not related to the trials commented that the trials and research methods were rigorous.
Phase 3 trials were approved on August 26 to take place in Moscow and include 40,000 individuals from the UAE, Saudi Arabia, the Philippines, and possibly Brazil. Of the 40,000 subjects, 30,000 would receive the vaccine and 10,000 would receive a placebo. Other countries, like Mexico, reportedly expressed interest in participating in Phase 3 testing in hopes of securing early supplies if the vaccine is proven effective.
The main concerns regarding the vaccine lie around its apparent rushed development and approval. It is currently unclear how Sputnik-V’s effectiveness compares to other vaccines developed by AstraZeneca and Moderna. Authors of the Lancet study stated that the levels of neutralizing antibodies produced were lower than AstraZeneca, while a Gamaleya Institute press release stated the opposite. The early approval of the vaccine prior to any large-scale clinical studies produced widespread skepticism and criticism from both international observers and Russians alike. Many fear that political pressures from the Kremlin to be the first country with a successful vaccine has led to an accelerated development cycle with potentially dangerous consequences. In April 2020, the Russian Federal Assembly repealed existing regulations requiring Phase 3 trials for any vaccine before it was eligible for official approval, meaning the conclusion of Phase 2 trials was sufficient for official approval and the beginning of production. The Kremlin reported that mass production would begin in September 2020 and achieve a final rate of 500 million doses per year. The Ministry of Health stated that availability to the general public would begin in late-November, though continued domestic skepticism towards safety and efficacy means adoption could be slower than expected. Ultimately, the vaccine’s safety for general use cannot be accurately determined until after Phase 3 trials where many potential side-effects, which might not have emerged in the small-scale trials of Phase 1 and 2, can be observed and studied.
Results from ongoing research and the current understanding of COVID-19 are constantly evolving. This post contains information that was last updated on October 26, 2020.