The advisory board consisting of outside experts announced its review on the efficacy and safety of the Pfizer vaccines, according to the Ministry of Food and Drug Safety. The panel's review is the first step of three separate independent evaluations before the ministry gives the final approval.

The panel advised the ministry to approve Pfizer's two full-dose regimen, saying it showed efficacy on all adults, including those aged between 16 and 17, and elders aged 65 and older.

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The panel reviewed Pfizer's clinical trials on 3,448 participants conducted in six countries, with half of them receiving the vaccine and half of them receiving a placebo.

The data showed that the vaccine demonstrated 95 percent efficacy in preventing COVID-19 in those without prior infection seven days or more after the second dose.

The panel said severe reactions were reported in less than 0.6 percent of vaccine recipients, but the rate was within the tolerable rate.

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The ministry said the result of the second review will be announced Thursday and the final approval will be announced Friday.

The vaccine by Pfizer will first start being provided to 58,500 health care workers treating COVID-19 patients Saturday.

Pfizer's vaccine is provided under the World Health Organization's global vaccine COVAX Facility project, and the shots will first be given at five state-run vaccination facilities as the products require ultra-cold chain storage.

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The authorities plan to further build 120 such facilities at general hospitals, gymnasiums and other kinds of government sites.