SGX Pharmaceuticals Provides Update on SGX523 Clinical Trials

SAN DIEGO, March 27 /PRNewswire-FirstCall/ -- SGX Pharmaceuticals (Nasdaq: SGXP) is providing an update today on the SGX523 clinical program.

In January 2008, the Company initiated two parallel, multi-center Phase 1 clinical trials of SGX523 in patients with solid tumor cancers. The first trial has been designed to examine twice daily, oral dosing on a continuous 28-day cycle and the second trial has been designed to examine interrupted dosing (a repeating 21 day cycle of 14 days on therapy followed by 7 days off).

In both trials, the Company observed dose limiting toxicity earlier than anticipated. The toxicity is of a nature that was not anticipated based on the preclinical profile of SGX523. The interrupted dosing trial started at a higher dose than the continuous dosing trial and no patients are currently receiving treatment on the interrupted dosing trial. In the continuous dosing trial, patients are continuing to be treated at a lower dose level, and the Company is evaluating the safety and efficacy of treatment at that dose level.

"From the initial clinical data, the profile of SGX523 appears to be different than the preclinical data would suggest," said Mike Grey, president and chief executive officer of SGX Pharmaceuticals. "On the continuous dosing trial, patients continue on study at the initial dose and we may explore whether alternative doses and schedules are safe and efficacious. We continue the preclinical development of the BCR-ABL inhibitor SGX393 and the second MET inhibitor SGX126. In addition, we are targeting the identification of two development candidates this year from our drug discovery programs to further enhance our pipeline."

Mr. Grey will be updating the investor community at 9:00 A.M. Eastern Daylight Time today at the BioCentury Future Leaders in the Biotech Industry Conference at the Millennium Broadway Hotel and Conference Center in New York City. A live webcast of the presentation will be available under the investor relations section of the Company's website at http://www.sgxpharma.com.

The Company filed its Form 10-K today and a copy can be found at www.sec.gov.

About SGX Pharmaceuticals

SGX Pharmaceuticals is a biotechnology company focused on the discovery, development and commercialization of innovative cancer therapeutics. The SGX oncology pipeline includes drug candidates from its FAST(TM) drug discovery platform, such as SGX523, a MET kinase inhibitor currently in Phase 1 clinical studies, next generation BCR-ABL inhibitors being developed by SGX and in partnership with Novartis and a portfolio of inhibitors of various oncology targets. More information on the pipeline and drug discovery platform can be found at www.sgxpharma.com and in the Company's various filings with the Securities and Exchange Commission.

Forward Looking Statements

Statements in this press release that are not strictly historical in nature are forward-looking statements. These statements include, but are not limited to, statements related to the Company's MET program, including the safety and efficacy profile and status of the clinical trials of SGX523, the advancement of the Company's drug development and discovery pipeline, the Company's ability to identify development candidates from its drug discovery programs and the potential of the Company's inhibitors as treatments for certain cancers. These statements are only predictions based on current information and expectations and involve a number of risks and uncertainties. Actual events or results may differ materially from those projected in any of such statements due to various factors, including the risks and uncertainties inherent in drug discovery, development and commercialization, which include, without limitation, the potential failure of development candidates to advance through preclinical studies or demonstrate safety and efficacy in clinical testing and the ability to file INDs or commence IND enabling activities or preclinical or clinical studies in the referenced time frames. The results of early preclinical studies or clinical trials may not be predictive of future results, and the Company cannot provide any assurances that any of its compounds or development candidates will have favorable results in preclinical studies or clinical trials. For a discussion of these and other factors, please refer to the risk factors described in the Company's annual report on Form 10-K for the year ended December 31, 2007, as well as other filings with the Securities and Exchange Commission. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof. This caution is made under the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. All forward-looking statements are qualified in their entirety by this cautionary statement and SGX undertakes no obligation to revise or update this press release to reflect events or circumstances after the date hereof.

SOURCE SGX Pharmaceuticals