Russia will start pre-clinical testing of two prototypes of the coronavirus vaccine on May 11, an official said on Saturday.

The samples have been passing the animal testing at the moment, and are expected to be finished by the end of April, head of the State Research Center of Virology and Biotechnology Rinat Maksyutov told reporters.

The scientists will then create substances for the pre-clinical and clinical testing, he said.

Russia has so far confirmed 4,731 coronavirus cases, and the disease took the lives of 43 people.

On Thursday, President Vladimir Putin extended the “non-working period” until April 30

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