2008-04-13 22:02:36 -

www.u3pharma.com - U3 Pharma Dr Irina Staatz-Granzer CEO t: +49 089 8103 9120 e: staatz-granzer@u3pharma.com or College Hill Dr Douglas Pretsell Account Director, Munich Bureau Chief t : +49 (0)89 57 00 18 06 e: douglas.pretsell@collegehill.com U3 Pharma, a translational medicine-focused oncology company, today announced that preclinical proof-of-concept has been established for its

lead product U3-1287 (AMG 888), the first fully human anti-HER3 monoclonal antibody (mAb). In vitro and in vivo studies of U3-1287 (AMG 888), which is being developed in partnership with Amgen, demonstrate that the antibody inhibits oncogenic signaling and proliferation of tumors. The results from these studies will be presented in two posters at the American Association for Cancer Research Annual Meeting in San Diego, California on April 13, 2008.

The target of U3-1287 (AMG 888) is a membrane-bound receptor tyrosine kinase called HER3, the third member of the human epidermal growth factor receptor (HER) family. HER3 controls a key signal transduction pathway in human malignancies and has shown involvement in multiple tumor types of epithelial origin, including breast, lung and colorectal cancers, among others. Using Amgen's Xenomouse(R) technology, U3 Pharma and Amgen generated this fully human anti-HER3 mAb and tested the in vitro and in vivo functional anti-tumor activities in relation to the target. The results showed that this anti-HER3 mAb was able to inhibit the growth of multiple tumor cell lines that are resistant to other HER family inhibitors. Additionally, administration of this anti-HER3 antibody demonstrated statistically significant growth inhibition of established xenograft tumors as a single agent or in combination with other HER family inhibitors.

"Our data suggest that U3-1287 (AMG 888) acting against HER3 has great potential as a novel agent for the treatment of epithelial cancers that are or have become resistant to other HER family inhibitors directed against EGFR or HER2," said Dr. Irina Staatz-Granzer, CEO of U3 Pharma. "We are eager to start clinical investigations as soon as possible and are optimistic that fully human anti-HER3 antibodies will become an important component in clinical applications and cancer research," she added.

U3 and Amgen now plan to submit an IND and hope to commence clinical investigations in multiple tumor types later this year.

About U3 Pharma

U3 Pharma AG is an emerging leader in targeted cancer drug development. The company has produced a pipeline of novel cancer antibodies based on discoveries made by its founder Prof. Axel Ullrich, whose pioneering work has led to the development of oncology blockbusters Herceptin(TM) and Sutent(TM). U3 Pharma applies its translational medicine expertise - pairing deep biological and disease-related knowledge, to drug discovery and development. The two lead antibodies are nearing the clinic as potential therapies for breast, lung and colorectal cancers, among others. For additional information, please visit www.u3pharma.com.

HER3 antibody a promising novel first-in-class HER family
inhibitor