The government is looking for 3,000 individuals who are willing to participate in the studies on using mixed coronavirus disease 2019 (Covid-19) vaccine brands, as well as Covid-19 booster shots, a Department of Science and Technology (DOST) official said on Thursday.

DOST Undersecretary Rowena Cristina Guevara said these individuals must be 18 years old and above, and those who belong in the government’s priority A1 to A4 categories in the vaccine rollout.

“(To address concerns on vaccine supply), they (participants) are also the ones who belong in the priority group. Thus, the (vaccine) supply would not decrease since the participants are also the ones scheduled to be inoculated,” she said.

There will be 12 experiments with 250 participants each. These experiments include using Sinovac vaccine as the first and second dose, and a different brand as the booster shot.

Guevara said these experiments would determine which combination increases the immune response of the participants.

“We are going to look at the efficacy. Would there be improvements (if you use different brands), or would you just get the same result (or efficacy),” she said.

The official also said while this kind of study is already being done abroad, they want to see its efficiency on Filipinos.

Meanwhile, Guevara said five brands — Sinovac, AstraZeneca, Pfizer, Moderna, and Sputnik V — will be involved in the clinical trials.

Local officials are targeting to start the study by July.

“This June will be the application for FDA (Food and Drug Administration) clearance to conduct the clinical trial, and (getting) the Ethics Review Board clearance,” Guevara said.