Innorna Co, a Chinese mainland's developer of messenger RNA drugs backed by buyout firm CDH Investments, is planning an initial public offering in the Hong Kong Special Administrative Region, according to people familiar with the matter.

The company is working with China International Capital Corp and Jefferies Financial Group Inc on a potential share sale that could take place as soon as next year, the people said, asking not to be identified because the information is private. Innorna could raise about $200 million in the IPO, one of them said.

Details of the offering such as size and timing are still preliminary and subject to change. Representatives for Innorna, CDH and CICC didn’t respond to requests seeking comment, while Jefferies declined to comment.

Innorna joins a growing number of mainland healthcare and biotech startups looking to list in the HKSAR as the sector finds favor with investors again. The Hang Seng Biotech Index has soared 86 percent this year and share sales by healthcare firms in the city have raised almost $12 billion, a four-year high, data compiled by Bloomberg show.

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Founded in 2019, Innorna develops lipid nanoparticle delivery systems and RNA therapies for infectious and rare diseases, metabolic disorders, and cancer immunotherapy. It raised $120 million in a funding round three years ago that was led by CDH and Huaxing Healthcare Fund.