MANILA — President Rodrigo Duterte was puzzled over why the Philippine drug regulator does not recommend use of COVID-19 shots from China's Sinovac Biotech for health frontliners, Malacañang said on Wednesday.

The Food and Drug Administration this week approved emergency use of the Sinovac vaccine CoronaVac. But the FDA said it is not advisable for use on medical workers because of the vaccine's 50.4-percent efficacy in a clinical trial in Brazil.

• Sinovac's COVID-19 vaccine not recommended for health workers - FDA

FDA Director General Eric Domingo said Tuesday the vaccine's efficacy declines if used on health workers who have direct exposure to COVID-19 patients. He said it is better suited for those who are healthy and are not exposed to coronavirus carriers.

• FDA: Efficacy ng Sinovac, bumababa sa health workers na mas exposed sa COVID-19

The World Health Organization only requires COVID-19 vaccines to hit at least a 50-percent efficacy rate, said Palace spokesman Harry Roque.

Sinovac is being distributed to health workers in Indonesia, he said.

"Si Presidente po mismo, nagtataka bakit ganoon ang naging EUA ng FDA," he told reporters in a televised briefing.

(The President himself is puzzled why the FDA's emergency use authorization was like that.)

"Kung ang WHO mismo ang nagsabi 50 percent is the threshold, ang tanong niya (Duterte), bakit kailangan mag-colatilla?" Roque added.

(If the WHO said 50 percent is the threshold, his question is why is a colatilla needed?)

Domingo explained his agency's advice during the Cabinet meeting on Monday, said Roque.

"Nirerespeto po ng Presidente ang opinyon ng mga experts kaya [we] let the colatilla remain," he added.

(The President respects the opinion of experts so we let the colatilla remain.)

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Health workers will not be banned from getting Sinovac shots, said Roque.

"Hindi lang po (it is just not) recommended, but if health care workers want, they can have it," he said. "That is also the language of the EUA."

• Sinovac COVID-19 vaccine safe for health workers, elderly, says GM

The first 600,000 shots of the Sinovac vaccine will arrive this month or in early March and help the Philippines kickstart its inoculation drive, behind some of its Southeast Asian neighbors.

The Philippines hopes to vaccinate up to 70 million people or two-thirds of its population against COVID-19 this year.

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