A consortium—consisting of entities affiliated with Shanghai Fosun Pharmaceutical Group, HOPU Investments, China Everbright’s Healthcare Fund and WuXi PharmaTech—has signed a merger agreement to acquire Ambrx. The transaction is expected to close in the second quarter of 2015, subject to receipt of certain regulatory approvals and satisfaction of customary closing conditions.

Ambrx is a San Diego, Calif.-based clinical-stage biotechnology company focused on discovering and developing first-in-class and best-in-class optimized protein therapeutics known as bio-conjugates. The company's proprietary technology platforms enable attachment of pharmaceutically active molecules to specific sites within proteins more precisely than prior generations of bio-conjugates and with precision similar to that used to design small-molecule drugs. Ambrx has developed a pipeline of novel product candidates that include antibody-drug conjugates, or ADCs, bi- and multi-specific drug conjugates, and long-acting therapeutic proteins.

ADCs are expected to be one of the most important areas of monoclonal antibody development in the next decade, especially in targeted therapies for oncology, an area where Ambrx has a strong internal pipeline. The company's most advanced internally developed product is ARX788, a site-specific ADC targeting Her2-positive breast cancer that Ambrx expects to begin clinical trials on in 2015.

In addition to its internal pipeline, Ambrx collaborates with pharmaceutical companies, including Bristol-Myers Squibb, Merck, Eli Lilly and Agensys. Ambrx's most advanced collaboration product candidate in human health is ARX618, a long-acting fibroblast growth factor 21 for type 2 diabetes, for which collaboration partner Bristol-Myers Squibb is conducting phase II clinical trials in the U.S. To date, collaborations have provided Ambrx with over $200 million in funding and have the potential to provide milestone payments and royalties on the sale of collaboration products.

Chen Qiyu, chairman of Fosun Pharma, said, "This joint acquisition will result in great synergy with Fosun Pharma's current R&D system and platform. Fosun Pharma has an internationalized R&D deployment in place with strong R&D capability. It has established an interactive and integrated R&D system in Shanghai, Chongqing and San Francisco, focusing on the R&D of macromolecular biopharmaceutical drugs, especially monoclonal antibodies. Under the help of Fosun Pharma, Ambrx's business expanding in China will enable Chinese patients to get faster access to innovative therapeutic drugs."