Ambrx, Inc., today announced the completion of a $23.4 million preferred stock financing. The funds will be used to advance Ambrx's lead product candidate, a human growth hormone with enhanced pharmacologic performance, into clinical development and to exploit the company's technology platform in other therapeutic applications. New investors in the company, including Maverick Capital, CMEA Ventures, Twilight Venture Partners and Alexandria Real Estate Equities, were joined by existing investors Tavistock Life Sciences, 5AM Ventures, Versant Ventures and Aravis Ventures. David Singer of Maverick Capital will join the Ambrx Board of Directors in connection with the close of the financing.

"This additional investment validates the power of Ambrx's approach to protein engineering as well as the rapid progress made in advancing the technology from its roots in an academic laboratory to delivery of a valuable drug candidate," said Richard DiMarchi, Chairman of the Board of Ambrx. "We are delighted to recruit such a strong group of investors as we move into the next phase of our development."

About Ambrx
Ambrx is a biopharmaceutical company committed to transforming the science and performance of protein-based medicines. Building on a fundamental advance in protein biosynthesis, Ambrx can genetically engineer proteins with novel amino acid building blocks beyond the common twenty. This approach represents a new paradigm in protein engineering and permits the pharmaceutical optimization of proteins in a manner analogous to that used for decades to improve the properties of traditional small molecule-based drugs and peptides. The company’s most advanced product candidate, a human growth hormone with superior performance, is currently in preclinical development with an IND filing anticipated in 2006. In addition, Ambrx is optimizing several other protein therapeutics representing large markets and significant unmet medical need.

For more information, please contact Troy Wilson, Ambrx’s Chief Business Officer at (858) 875-2505 or visit www.ambrx.com.