HONG KONG – Ambrx Inc. and Zhejiang Hisun Pharmaceuticals Co. Ltd. (SH:600267) inked a deal to develop and commercialize bispecifics based on Ambrx's research with an aim to develop new oncology therapies.

"Hisun represents a strong strategic partner with the right regulatory and manufacturing expertise," said Ambrx CEO Lawson Macartney. "We believe that this collaboration is additional validation of our technology platform and its potential for many clinical applications."

Under terms of the agreement, Hisun will have commercial rights to market the products in China while Ambrx will have marketing rights for the rest of the world. Hisun will pay Ambrx royalties on sales of the drugs and will be the manufacturer of the products. Ambrx will also be responsible for worldwide clinical and commercial supply.

"This partnership will help Hisun to expand our pipeline and advance our position in the biopharmaceutical industry across the globe," said Bai Hua, CEO and chairman of Hisun.

The financial details of the deal were not disclosed. But the numbers are unlikely to be particularly high.

"There's not a large amount of money involved in this deal," a spokeswoman at Hisun told BioWorld Today.

Hisun has been active in other fronts at the same time.

The company's first biologic product, a biosimilar, is undergoing review process by the Center for Drug Evaluation (CDE), the drug evaluation arm of the CFDA.

"We haven't launched any biopharmaceuticals so far, but we have a biosimilar version of Enbrel currently filing for manufacturing approval," the spokeswoman told BioWorld Today.

Hisun has developed Anbainuo (as the name would translate from Chinese), a biosimilar version of Etanercept. The drug is a recombinant type II human tumor necrosis factor receptor that treats autoimmune diseases such as rheumatoid arthritis, ankylosing spondylitis. The originator drug, Enbrel, was developed and marketed by Pfizer Inc. Sales of Enbrel topped $8 billion by 2013, making it the fourth best-selling drug in the world, according to IMS Health.

Hisun is one of several Chinese and Indian pharmaceutical companies that have stepped up their efforts to develop biosimilar versions of Etanercept attracted by the huge market potential and the large populations of the two countries.

An example is Shanghai CP Guojian Pharmaceutical Co. Ltd., which launched its own biosimilar version of Etanercept under the name Yisaipu in 2006. Yisaipu has had great success in the China market since its launch.

India's Lupin Ltd. has also been developing its own biosimilar Etanercept. The drug will be the first product to be manufactured by a new joint venture with Japanese drug maker Yoshindo Inc. that was announced in late April. (See BioWorld Today, April 28, 2014.)

Hisun said in its 2013 annual report that Anbainuo has already undergone clinical trials. The company is waiting for the green light from authorities to produce the biosimilar drug and has a reserved product system ready for the future development of biopharmaceuticals.

Hisun's plan is to produce 3.2 million doses of Anbainuo per year, a plan backed by the National Strategic Emerging Industries Development Special Fund of the Chinese government. Hisun is expecting to receive as much as ¥50 million (US$8 million) from the fund for this project.

Hisun also has a project under way with Pfizer. In September 2012 the company announced the launch of the joint venture Hisun-Pfizer Pharmaceuticals Co. Ltd. Hisun-Pfizer is responsible for developing, manufacturing and commercializing off-patent pharmaceutical products in China and global markets.

The newly announced agreement with Hisun is not Ambrx's first deal with a Chinese pharmaceutical company either.

China's Zhejiang Medicine Co. Ltd. has an agreement with Ambrx to develop and commercialize Ambrx's ARX 788, the company's most advanced site-specific antibody drug conjugate for the treatment of HER2-positive breast cancer currently under development.