Russian scientists have published an article in the authoritative scientific journal "The Lancet" about the test results of their coronavirus vaccine. The publication claims that the Russian drug is capable of creating immunity against Covid-19 in the human body. But Western experts warn that there is still a long way to go before the vaccine is widely used.
The article claims that all of the patients participating in the trials developed antibodies to fight the virus and did not have any serious side effects. We are talking about a vaccine called "Sputnik-V", which was developed by The Gamaleya Research Institute together with the Russian Ministry of Defense.
Russia became the first country in the world to approve a coronavirus vaccine. On August 11, the President Vladimir Putin announced that the drug was registered, and one of his daughters had already been vaccinated.
Many Western experts said that the scale of clinical trials was too small to prove the effectiveness and safety of the  vaccine. Some scientists also noted that the Russian development is used very quickly, which may testify to the nonobservance of all the necessary procedures.
However, Moscow insists that the results of the study, published in the Lancet, answer all the critics' claims.
The Russian coronavirus vaccine has generated an immune response in one hundred percent of volunteers who took part in the clinical trials. It is safe and has a long-term effect.
“In the study of the immunogenicity of the Sputnik V vaccine, all volunteers registered an immune response not only at the humoral level, but also at the cellular level, which is very important,” says Inna Dolzhikova, MD.
The tests showed that the immune response to COVID-19 that the volunteers have after the usage of the Russian vaccine significantly exceeds the immunity of patients who have already had coronavirus, the scientist noted. Another important point: the presence of preexisting immunity in people, who have had other diseases, does not affect the effectiveness of the Russian vaccine.

The vaccine, known as Sputnik V, went through two series of clinical trials in June and July this year. Each enrolled 38 healthy volunteers, ages 18 to 60, who received the first dose of the vaccine and three weeks later an additional dose (also known as a booster).

Doctors monitored the health of the participants in the trials for 42 days, and antibodies to coronavirus were formed in their blood in three weeks. The most common side effects were headache and joint pain.

The trials were not random and did not use a placebo, meaning all volunteers knew they were getting the Covid-19 vaccine. "To ensure the long-term safety and efficacy of the vaccine to prevent Covid-19 infection, full-scale and long-term trials are required, including comparison with placebo," the publication said.
The authors of the article report that 40 thousand volunteers from "different risk groups and different ages" will take part in the third phase of the trial.
A modified adenovirus that causes the common cold was used in the development of the Russian vaccine.

Some British scientists think the results of the study are "encouraging" - "so far everything is going well," they say. Yet vaccine developers still have a long way to go.

Although all study participants developed the antibodies in the second phase, this does not necessarily mean protection from the coronavirus. This remains to be determined.
From these results, it can be concluded that the vaccine is safe for healthy people between the ages of 18 and 60 for 42 days, as the study was made during this timeframe. But what is the situation with those for whom Covid-19 poses the greatest risk: older people - or those with serious chronic illnesses? How safe will the vaccine be for them - and over the longer term period?
These questions can only be answered after much larger, long-term and randomized (that is, randomly assigning volunteers to groups) trials in which participants will not know if they are receiving a vaccine or a placebo.
Such trials will also allow scientists to find out how effective the vaccine is for different populations.
The Russian authorities say it is the world's first vaccine against Covid-19. And it was indeed the first to be officially registered. But at least one more vaccine has previously been approved in China - developed by CanSino Biologics - and has been used by the Chinese military since June 25. 
In addition, the Russian vaccine was registered only for providing emergency assistance to certain groups of the population (most likely, the military and some doctors). The Russian authorities also emphasize that the registration could be revoked if the third phase of testing fails.
This temporary registration is due to end on January 1, 2021. By this time, it is planned to complete the third phase of clinical trials - and if successful, the vaccine will be approved for the public usage.
The tests during the first and second phases were rather limited, which raises some concerns.
Standard practice is a three-stage clinical trial that tests the safety, immune response, and the safe use of a vaccine in a variety of populations, including those at particular risk of the virus.

According to the WHO, 176 different coronavirus vaccines are currently being developed worldwide, 34 of them are currently being tested in humans, including eight are in the third, final phase of clinical trials.