The Philippines started its nine-month clinical trials for Avigan on Monday to study the efficacy of the Japanese anti-flu drug against the disease caused by the new coronavirus.

Health Undersecretary Maria Rosario Vergeire said the clinical trials will include just four hospitals in Metro Manila initially but more will be included in the future.

Supplied photo shows tablets of the anti-influenza drug Avigan. (Photo courtesy of Fujifilm)(Kyodo)

"The list of hospitals will be expanded for us to be able to have these 100 patients who will receive the allocated drugs coming from the Japanese government," Vergeire told a press conference, adding that there have sufficient stocks of the drug.

Avigan is the brand name of favipiravir, an antiviral drug manufactured by a subsidiary of Japanese firm Fujifilm Holdings Corp., which is seen as a potential treatment for COVID-19, a respiratory disease caused by the novel coronavirus.

Clinical trials on Avigan will be an "open label, multicenter, randomized comparative study," Vergeire said last week, with participants split into two study groups.

The first set of patients will be given the existing supportive care provided at the hospitals. The second group will receive the same on top of being administered with the drug.

The Philippine official added that only people aged between 18 and 74 can participate in the trials, and they must be willing to use contraceptives during the duration of the study.

Vergeire said contraceptives are needed as the drug is teratogenic, meaning it could cause birth defects.

A total of 18 million pesos ($366,000) has been allocated by the Philippine government for the clinical trials.

Fujifilm Holdings said last Thursday it expects to complete clinical tests in Japan of Avigan in September and seek approval.

Japanese Prime Minister Shinzo Abe had earlier this year expressed hope to have Avigan approved in May but a Japanese university's interim report, released that month, did not indicate clear efficacy of the drug in treating COVID-19.

In the Philippines, 164,474 cases of COVID-19 have been recorded as of Monday, including 2,681 deaths.

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