Chi-Med, which is already listed on the London Stock Exchange and the Nasdaq in New York, filed its listing application with the Hong Kong stock exchange on Monday.

"We are delighted to announce our proposed Hong Kong listing and global offering of shares," said Simon To, Chairman of Chi-Med, which is 60.2 percent owned by CK Hutchison.

Chi-Med's statement did not say how much it planned to raise.

The company did say it expected to use net proceeds from any primary sale of shares in the offering to fund the late-stage clinical development of its global and China pipeline and advance its pipeline of clinical-stage drug candidates.

Chi-Med also said it wanted to list in Hong Kong to improve liquidity for shareholders and strengthen its access to capital.

The deal, which also includes a secondary share sale by parent CK Hutchison Holdings, could raise up to $500 million, the people said, with one saying the size would be between $400 million and $500 million. Another source said the deal size would likely be around $300 million.

Deal sizes can change and are often smaller than the original target size.

CK Hutchison plans to reduce its stake to below 50 percent and will include a secondary share sale as part of the Hong Kong listing.

Hong Kong has sought to transform itself into a listing hub for emerging biotech companies to compete with other financial centres such as New York by changing its listing rules to allow companies with no revenues in the sector to list.

While the first few listings performed poorly, the two biotech companies that completed their initial public offerings (IPOs) in Hong Kong this year have done well.

CanSino Biologics is up 89 percent from its IPO price while CStone Pharmaceuticals is up 30 percent from its offer price.

Two sources said the company was aiming for a listing by the summer.

Chi-Med reported a loss of $74.8 million on revenues of $214.1 million in 2018, its draft IPO prospectus showed. It loss in 2017 was $26.7 million on revenues of $241.2 million.

Bank of America Merrill Lynch and Goldman Sachs are joint sponsors for the Chi-Med listing.

(Reporting by Julia Fioretti. Editing by Jane Merriman)

By Julia Fioretti and Julie Zhu