MOSCOW, Aug 11 (Reuters) - President Vladimir Putin said on Tuesday that Russia had become the first country in the world to grant regulatory approval to a COVID-19 vaccine after less than two months of human testing, a move hailed by Moscow as evidence of its scientific prowess.
The vaccine still has to complete final trials, raising concerns among some experts at the speed of its approval, but the Russian business conglomerate Sistema has said it expects to put it into mass production by the end of the year.
Russian health workers treating COVID-19 patients will be offered the chance of volunteering to be vaccinated in the coming weeks, a source told Reuters last month.
Regulatory approval paves the way for the mass inoculation of the Russian population and authorities hope it will allow the economy, which has been battered by fallout from the virus, to return to full capacity.
Kirill Dmitriev, head of Russia's sovereign wealth fund, hailed the development as a historic "Sputnik moment", comparable to the Soviet Union's 1957 launch of Sputnik 1, the world's first satellite.
The vaccine will be marketed under the name 'Sputnik V' on foreign markets, he said.
Dmitriev said Russia had already received foreign requests for 1 billion doses. International agreements had been secured to produce 500 million doses annually, with the vaccine also expected to be produced in Brazil.
He said clinical trials were expected to start soon in the United Arab Emirates and the Philippines.
But only about 10% of clinical trial are successful, and the speed at which Russia has moved, approving a vaccine before the final stages of trials to test safety and efficacy are over, has worried some scientists, who fear Moscow may be putting national prestige before safety.
Speaking at a government meeting on state television, Putin dismissed those concerns, saying the vaccine, developed by Moscow's Gamaleya Institute, was safe and that it had even been administered to one of his daughters.
"I know that it works quite effectively, forms strong immunity, and I repeat, it has passed all the needed checks," said Putin.
He said he hoped mass production would start soon.
The vaccine's approval by the health ministry comes before the start of a larger trial involving thousands of participants, commonly known as a Phase III trial.
Such trials, which require a certain rate of participants catching the virus to observe the vaccine's effect, are normally considered essential precursors for a vaccine to receive regulatory approval.
The Moscow-based Association of Clinical Trials Organizations (ACTO), a trade body representing the world's top drugmakers in Russia this week urged the health ministry to postpone approval until that final trial had been successfully completed.
In a letter to the ministry, it said there were high risks associated with registering a drug before that happened.
"It is during this phase that the main evidence of a vaccine's efficacy is collected, as well as information on adverse reactions that could appear in certain groups of patients: people with weakened immunity, people with concomitant diseases and so forth," it said.
Some international experts have also questioned the speed at which Russia approved its vaccine.
"Normally you need a large number of people to be tested before you approve a vaccine," said Peter Kremsner from the University Hospital in Tuebingen, currently testing CureVac's COVID-19 vaccine in clinical trials.
"In that respect, I think it's reckless to do that (approve it) if lots of people haven't already been tested."
Duncan Matthews, a professor of intellectual property law at Queen Mary University of London, said news of a potential COVID-19 vaccine was to be welcomed, "but safety must be the priority".
"The U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) have fast-track approval procedures for emergency humanitarian use and we need to see evidence that Russia is adopting an equally prudent approach," Matthews said in an emailed comment.
More than 100 possible vaccines are being developed around the world to try to stop the COVID-19 pandemic. At least four are in final Phase III human trials, according to WHO data.