China-based drug maker Hansoh Pharmaceutical Group Co. Ltd. is close to raising between $500 million and $1 billion through a Hong Kong stock market listing.

Hansoh Pharmaceutical, with $1.1 billion in revenue and more than $280 million in profits, has filed again for a Hong Kong initial public offering (IPO).

New York-based investment bank and financial services company Citigroup and peer Morgan Stanley are joint sponsors for the IPO.

Hansoh Pharmaceutical will use the IPO proceeds for research and development, including existing and future domestic and overseas drug development, upgrading and building production lines, and promotional purposes.