GENEVA, February 24 /PRNewswire/ -- Merck Serono, a division of Merck KGaA, Darmstadt, Germany, and Ambrx Inc, today announced a global strategic collaboration to develop and commercialize Ambrx's ARX424 preclinical product candidate for the treatment of multiple sclerosis. ARX424 was created by Ambrx through the application of its proprietary protein optimization technology, ReCODE(TM).

This second collaboration between the two companies follows a previous agreement announced in 2007 to develop ARX201, Ambrx's long-acting growth hormone product, currently in Phase II of clinical development.

Under the terms of the agreement, Merck Serono will receive worldwide exclusive development and commercialization rights for ARX424. Merck Serono will make an initial payment to Ambrx, and Ambrx is eligible to receive undisclosed clinical, regulatory and commercial milestone payments based upon the successful development and commercialization of potential products resulting from this collaboration, as well as undisclosed royalties on the associated worldwide net sales. Ambrx also retains the option to convert its right to receive royalties in the U.S. to a profit and loss sharing option. If the option is exercised, Ambrx and Merck Serono will share global development expenses, US commercialization expenses as well as profit. In addition, Merck Serono will make an undisclosed equity investment in Ambrx. Additional terms of the collaboration were not disclosed.

This second collaboration with Ambrx not only demonstrates their robust research and development capability, it also strengthens our partnership to deliver innovative products to the market to help improve the quality of life of patients, said Vincent Aurentz, Executive Vice President Portfolio Development at Merck Serono.

We are pleased to expand our productive relationship with Merck Serono, a company ideally suited to harness the potential of our growth hormone and multiple sclerosis product candidates given their franchises in these areas, said Stephen Kaldor, Ph.D., Ambrx President and Chief Executive Officer. While we are operating from a strong cash position, we felt it appropriate that Merck Serono make an equity commitment as part of this transaction to further strengthen and align our interests going forward.

About Ambrx

Ambrx Inc. is a clinical stage biopharmaceutical company with a broad biologics platform that allows it to create best-in-class protein therapeutics, including improved versions of native proteins and therapeutic antibodies. Its most advanced product candidate, ARX201, is a long-acting human growth hormone drug candidate partnered with Merck Serono that has successfully completed initial clinical trials. The company has further validated its biologics platform through substantial partnerships with Eli Lilly and Company and Merck Co. Ambrx is advancing a robust portfolio of product opportunities spanning multiple therapeutic areas that are highly optimized for efficacy, safety, and ease of use. For additional information, call 858.875.2400 or visit http://www.ambrx.com.

About Merck Serono

Merck Serono is the division for innovative prescription pharmaceuticals of Merck, a global pharmaceutical and chemical group. Headquartered in Geneva, Switzerland, Merck Serono discovers, develops, manufactures and markets innovative small molecules and biopharmaceuticals to help patients with unmet medical needs. Its North American business operates in the United States and Canada as EMD Serono.

Merck Serono has leading brands serving patients with cancer (Erbitux(R), cetuximab), multiple sclerosis (Rebif(R), interferon beta-1a), infertility (Gonal-f(R), follitropin alfa), endocrine and cardiometabolic disorders (Glucophage(R), metformin); (Concor(R), bisoprolol); (Euthyrox(R), levothyroxine); (Saizen(R) and Serostim(R), somatropin). Not all products are available in all markets.

With an annual RD expenditure of around EUR 1bn, Merck Serono is committed to growing its business in specialist-focused therapeutic areas including neurodegenerative diseases, oncology, fertility and endocrinology, as well as new areas potentially arising out of research and development in autoimmune and inflammatory diseases.

About Merck

Merck is a global pharmaceutical and chemical company with total revenues of EUR 7.6 billion in 2008, a history that began in 1668, and a future shaped by 32,800 employees in 59 countries. Its success is characterized by innovations from entrepreneurial employees. Merck's operating activities come under the umbrella of Merck KGaA, in which the Merck family holds an approximately 70% interest and free shareholders own the remaining approximately 30%. In 1917 the U.S. subsidiary Merck Co. was expropriated and has been an independent company ever since.

For more information, please visit http://www.merckserono.com or http://www.merck.de

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