Ambrx Inc. announced today that it has been issued U.S. Patent No. 7,045,337 entitled "In vivo incorporation of unnatural amino acids."

The patent covers Ambrx’s core ReCODE™ technology, which serves as the basis for the development of its product candidates. The patent, which broadly claims the in vivo incorporation of unnatural amino acids into proteins, is not limited by the type of cell, tRNA synthetase, tRNA, unnatural amino acid, selector codon or resultant protein.

“The issuance of this patent is a significant event because it broadly claims our technology platform and will add value to our company and collaborators,” said Martin A. Mattingly, Pharm.D., Ambrx’s president and chief executive officer. “The patent also includes a claim to human growth hormone that was produced using the patented technology.”

The patent rights were exclusively licensed by Ambrx from The Scripps Research Institute, where the technology was developed in the laboratory of Peter G. Schultz, Ph.D. Ambrx has further developed the technology since acquiring these rights.

“This patent anchors the extensive intellectual property portfolio we have developed at Ambrx,” said Thomas O. Daniel, M.D., Ambrx’s chief scientific officer. “This intellectual property covers broad-ranging technology that has enabled us to develop our leading product candidate, ARX-201, a long-acting human growth hormone that should reduce the number of injections children must endure for effective treatment.”

All issued U.S. patents can be viewed on the Web site of the U.S. Patent and Trademark Office at www.uspto.gov.

About Ambrx
Ambrx is a biopharmaceutical company focused on optimizing existing protein drugs. Using its technology, the company can overcome the performance challenges of high-value commercial proteins by improving their efficacy, safety and ease of use. Ambrx’s core ReCODE™ technology allows for the precise, site-specific substitution of a novel amino acid within a protein. This technology is applicable to multiple protein products across numerous therapeutic areas. Ambrx expects to initiate clinical trials with a long-acting, PEGylated human growth hormone in early 2007, followed by an enhanced, PEGylated interferon alpha molecule. With its innovative approach, Ambrx has successfully bridged the gap between a platform that works and drug development. For additional information, call 858.875.2400 or visit www.ambrx.com.

Ambrx® and ReCODE™ are trademarks of Ambrx, Inc.