South Korea's drug safety agency on Wednesday approved an authorization of US-based biotechnology company Novavax Inc.'s COVID-19 vaccine.

The protein-based vaccine, Nuvaxovid, marks the fifth COVID-19 vaccine to get approval for use here, following the ones by British-Swedish pharmaceutical giant AstraZeneca and Oxford University, Pfizer Inc., Johnson & Johnson and Moderna Inc.

The Ministry of Food and Drug Safety convened a panel of experts from both inside and outside to review the safety and efficacy of the two-dose regimen, after reviewing two sets of studies.

The approved vaccines will be distributed by SK Bioscience Co., a unit of South Korea's SK Group, after being manufactured at its local plant.

The vaccine will be administered to people aged 18 or older, and a second injection will be administered 21 days after the first, the ministry said.

The first study, conducted in Mexico and the United States, found a 90.4-percent reduction in the number of symptomatic COVID-19 cases.

The second study, conducted in Britain, also showed a similar reduction in the number of symptomatic COVID-19 cases, with a vaccine efficacy of 89.7 percent.

The side effects observed in the studies were usually mild or moderate, and cleared within a couple of days after the inoculation, the ministry said.

The ministry said the Novavax vaccine can be stored at a refrigerator temperature of between two and eight Celsius for up to five months.

Existing vaccine supply channels with more traditional cold chain capabilities will be used to store the products, the ministry said.

SK Bioscience has reserved manufacturing capacity at its plant in Andong, about 270 kilometers south of Seoul, for the production of Nuvaxovid through 2022.

Nuvaxovid is a protein-based vaccine engineered from the genetic sequence of the first strain of SARS-CoV-2, the virus that causes COVID-19.

The vaccine has so far gotten authorizations from European Union regulators, the World Health Organization, as well as several Asian countries. The company has said it will also submit a request to the US Food and Drug Administration. (Yonhap)