* Ascentage picks Hong Kong over U.S. due to new HKEX rules -chief
* Ascentage planning to raise up to $300 mln - sources
* Innovent Biologics looking to raise $300 mln-$500 mln - sources
By Julie Zhu and Fiona Lau
HONG KONG, April 26 (Reuters) - Two Chinese biotechs have axed plans to list in New York and instead aim to raise up to $800 million in Hong Kong IPOs, seeking to cash in on new rules to woo early-stage drug developers, sources said.
Fidelity Investments-backed Innovent Biologics and Ascentage Pharma both plan to float in the second half of this year and are working with several advisers, they added.
They join a growing queue of Chinese biotechs targeting IPOs in Hong Kong, which will, as of April 30, allow firms in the sector with no profits or revenues to list, though some participants doubt if the market, dominated by traditional companies, will painlessly cope with the new-age sector.
The new rules are part of a broader effort by Hong Kong Exchanges and Clearing (HKEX) to encourage more new economy companies to float in the city as it battles New York to be the world's largest listings hub.
Both Innovent and Ascentage have yet to log any revenues.
Ascentage, which focuses on therapeutics for cancers, hepatitis B and aging-related diseases, is aiming to raise up to $300 million, two sources said.
"We were already ready to file (an IPO application) in the United States, but we have shifted to Hong Kong for listing as the HKEX opens its doors to us," Ascentage's chairman Yang Dajun told Reuters.
"This is great news for biotech firms which are based in China and want to tap more Chinese and Asian investors," he said of Hong Kong's rule change, but declined to elaborate further about his firm's IPO plan.
Suzhou-based Innovent, which counts mutual fund giant Fidelity and Singapore state investor Temasek among its investors, is looking to raise between $300 million and $500 million in its Hong Kong float, according to two other sources.
Innovent declined to comment on its IPO plans.
The two companies chose Hong Kong because of the city's new listing regime, its familiarity with Chinese firms, potentially higher valuations and its convenient timezone for mainland executives, the sources said.
Innovent and Ascentage will be following Shanghai Henlius Biotech, backed by Chinese conglomerate Fosun International, diabetes-focused drug developer Hua Medicine and U.S.-based cancer detection start-up Grail, among others, in eyeing Hong Kong listings.
That rush is making some market participants question if Asian investors can adequately cope with the complexities of biotech sector investing.
"The U.S. has very mature investors for the sector, but the Asian investors are quite new to it," said Li Hang, head of Greater China equity capital markets at investment bank CLSA.
Founded in 2011, Innovent has built a portfolio of 16 potential products for treating cancer, autoimmune disorders and other diseases, and seven of those are in clinical development. It has also partnered with Eli Lilly to co-develop three cancer treatments in China and overseas.
Ascentage, founded in 2010, has seven products in clinical development and 17 in total approved for clinical studies in China, the United States and Australia. Besides U.S. Oriza Ventures, it also counts Chinese state-backed SDIC Fund Management among its investors. (Reporting by Julie Zhu and Fiona Lau, IFR; Editing by Jennifer Hughes and Muralikumar Anantharaman)