UPDATE 1-S.Korean vaccine firm SK Bioscience sees shares soar 30% on debut

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SEOUL, March 18 (Reuters) - South Korean firm SK Bioscience Co Ltd shares rocketed 30% on their first day of trading on Thursday, as investor bets on the COVID-19 vaccine developer and maker’s prospects turned it into a nearly $12 billion business.

The stock opened on Seoul’s KOSPI market at 130,000 won per share, double the IPO price of 65,000 won, then quickly jumped to 169,000 won in early trade, valuing the company at 12.9 trillion won ($11.5 billion).

The vaccine developer, in which SK Chemical holds a 68.4% stake, raised 1.5 trillion won in the country’s largest initial public offering since mobile game developer Netmarble raised 2.7 trillion won in May 2017, according to Korea Exchange data.

SK Bioscience has agreements to produce COVID-19 vaccines for AstraZeneca and Novavax Inc in Korea, and received regulatory approval in November to begin clinical trials of its own COVID-19 vaccine. (Reporting by Joyce Lee and Jihoon Lee; Editing by Christopher Cushing and Kenneth Maxwell)