SK Bioscience Co., a vaccine unit of South Korea's SK Group, said Friday it has extended an agreement to manufacture a component of the US-based biotechnology company Novavax Inc.'s COVID-19 vaccine by one more year.

Under the extended agreement, SK Bioscience will reserve additional manufacturing capacity to produce antigen, a key component of NVX-CoV2373 -- Novavax's recombinant protein-based COVID-19 vaccine -- through 2022.

Last year, the two sides initially signed the agreement to reserve manufacturing capacity at SK Bioscience's plant in Andong, about 270 kilometers south of Seoul, for the production of NVX-CoV2373 through 2021. 

Under the new agreement, SK bioscience also acquired non-exclusive rights to sell doses of Novavax's vaccine to Thailand and Vietnam.

The agreement between the companies also builds on a previously announced advance purchase agreement between SK bioscience and the South Korean government to supply 40 million doses of Novavax's vaccines to South Korea.

NVX-CoV2373 is a protein-based vaccine engineered from the genetic sequence of the first strain of SARS-CoV-2, the virus that causes COVID-19. (Yonhap)