Senator Grace Poe has likened to "drug pushing" the insistence of officials to purchase and use the COVID-19 vaccines from Sinovac Biotech for the government's inoculation program.

"Hindi ba talagang parang pinagpipilitan nila itong isang kumpanya na ito (They are really insisting on this company, aren't they). Isn’t that a form of drug pushing?" Poe said during their Monday plenary session after Sen. Panfilo Lacson's privilege speech.

"Parang ‘yon ang kanilang ipinipilit doon sa ating pag-uusap (It appeared during our discussions that they were insisting on that). In fact, wala pa ngang FDA approval pero nag-commit na, ilan ba, 25,000 will be vaccinated by February (In fact, even before the Food and Drug Administration's approval, they have already committed that some 25,000 will be vaccinated by February)," she added.

The government earlier secured 25 million doses from Sinovac, with authorities saying that an initial 50,000 will be delivered to the country by February.

The China-based biopharmaceutical firm has yet to obtain an emergency use authorization (EUA) from the FDA for its vaccines.

Lacson, who, in his speech, questioned the lack of transparency on the government's price negotiations with Sinovac, agreed with Poe's observation.

"Yes, Mr. President. And whoever was mainly responsible for pushing hard ‘yong (the) Sinovac, it eventually became their own undoing," he responded.

"Wala naman tayong ina-accuse (We are not accusing anybody), we’re not prepared to accuse anybody of corruption. But the fact remains that seemingly there’s an overprice of so much if we insist in procuring this vaccine," he added.

Senator Joel Villanueva, meanwhile, said government's vaccine selection should based on science and evidence

"Underlying all of this is science, which is non-negotiable. Evidence-based selection. We should go where the hard science leads us," he said in a statement.

"So, when we say science then it means we do not blindly express preference for vaccine based on its country of origin. Hindi po porke’t (Not because) they come in packaging with Chinese characters, we express preference na kaagad (immediately) even in the absence of a review by our own scientists," he said.

The acquisition of the Chinese vaccines, he said, must not have an "express lane".

"Ang Chinese vaccines sa ngayon ay hindi POGO workers na may immigration express lane (Chinese vaccines are not like Philippine offshore gaming operations workers who have an immigration express lane. Pero kung proven na mabisa (But if proven effective) then let us roll out the red carpet for these vaccines,” he said.

Administration officials, including President Duterte have repeatedly denied preference for any specific COVID-19 vaccine, although they have also defended the government's decision to purchase Sinovac's product.

Senators were critical about this due to the vaccine's reportedly low efficacy rate and high cost, which authorities also negated.

The Senate is set to continue its public hearings on the government's vaccination program on Friday, January 22.