Russia will start giving its first drug approved to treat COVID-19 to patients next week, its state financial backer told Reuters.

Russian hospitals can begin giving the antiviral drug, which is registered under the name Avifavir, to patients from June 11, the head of Russia’s RDIF sovereign wealth fund told Reuters in an interview. He said the company behind the drug would manufacture enough to treat around 60,000 people a month.

Russian scientists modified a Japanese drug

Avifavir, known generically as favipiravir, was first developed in the late 1990s by a Japanese company later bought by Fujifilm as it moved into healthcare.

RDIF head Kirill Dmitriev said Russian scientists had modified the drug to enhance it, and said Moscow would be ready to share the details of those modifications within two weeks.

Japan has been trialling the same drug, known there as Avigan. It has won plaudits from Prime Minister Shinzo Abe and $128 million in government funding, but has yet to be approved for use.

Avifavir appeared on a Russian government list of approved drugs on Saturday.

Avifavir treated the virus in most cases within four days

Dmitriev said clinical trials of the drug had been conducted involving 330 people, and had shown that it successfully treated the virus in most cases within four days.

The trials were due to be concluded in around a week, he said, but the health ministry had given its approval for the drug’s use under a special accelerated process and manufacturing had begun in March.

Dmitriev said Russia was able to cut testing timescales because the Japanese generic drug which Avifavir is based on was first registered in 2014 and had undergone significant testing before Russian specialists modified it.

We believe this is a game changer. It will reduce strain on the healthcare system, we’ll have fewer people getting into a critical condition,” said Dmitriev. “We believe that the drug is key to resuming full economic activity in Russia.”

With 414,878 cases, Russia has the third highest number of infections in the world after Brazil and the United States, but has a relatively low official death toll of 4,855 - something that has been the focus of debate.