STA-4783 Data to be Presented at the First Worldwide Melanoma Center Meeting of the European Association of Dermato-Oncology.

LEXINGTON, Mass. -- Synta Pharmaceuticals Corp., (NASDAQ: SNTA) a biopharmaceutical company focused on discovering, developing, and commercializing small molecule drugs to treat severe medical conditions announced that Dr. Steven O'Day, Chief of Research and Director of the Melanoma Program at The Angeles Clinic and Research Institute in Los Angeles, will present an update on the results of a Phase 2b study of STA-4783 in combination with paclitaxel compared to paclitaxel alone in the treatment of metastatic melanoma at the European Association of Dermato-Oncology (EADO) in Barcelona, Spain, September 6-8, 2007.

"STA-4783 is the first drug in over 30 years to demonstrate an improvement in progression free survival in a double-blind, randomized, controlled, multi-center clinical trial in metastatic melanoma," said Dr. O'Day. "In a disease where there are so few treatment options for patients, it is vitally important to continue the development of new therapeutics such as STA-4783."

Dr. O'Day was the lead investigator on the Phase 2b trial of 81 patients with Stage IV melanoma, and will be the North American lead investigator for the Phase 3 trial of STA-4783. Synta has announced that it plans to initiate an international Phase 3 clinical trial to investigate STA-4783 as a first-line therapy for patients with metastatic melanoma in the third quarter of 2007.

About STA-4783

STA-4783 is a novel, injectable, small molecule investigational drug candidate that induces a potent oxidative stress response in cancer cells, driving programmed cell death and enhancing the activity of anti-cancer agents that act through the mitochondrial apoptosis pathway, including paclitaxel. In November 2006, Synta received Fast Track designation from the FDA for the development of STA-4783 in metastatic melanoma.

Based on the broad-acting potential of its novel mechanism of action and the activity seen in laboratory experiments in other cancer types, Synta plans to investigate the use of STA-4783 in additional cancers and in combination with other agents, including announcing one or more Phase 2 studies in other cancer indications later in the year.

About Metastatic Melanoma

Melanoma, the most deadly form of skin cancer, arises from melanocytes, the pigment-producing cells of the skin. According to the American Cancer Society, melanoma accounts for approximately five percent of all skin cancers but causes about 75% of all skin cancer-related deaths. An estimated 60,000 people will be diagnosed and nearly 8,200 people will die from melanoma this year in the U.S. alone. If diagnosed and surgically removed while localized in the outermost skin layer, melanoma is potentially curable; however, for patients with metastatic disease the prognosis is poor with limited available treatments and an expected survival of only six to nine months. The incidence of melanoma has increased more rapidly than any other cancer during the past ten years. The FDA has not approved a novel, small molecule drug for the treatment of metastatic melanoma in over 30 years.

About Synta Pharmaceuticals

Synta Pharmaceuticals Corp. is a biopharmaceutical company focused on discovering, developing, and commercializing small molecule drugs to extend and enhance the lives of patients with severe medical conditions, including cancer and chronic inflammatory diseases. Synta has a unique chemical compound library, an integrated discovery engine, and a diverse pipeline of clinical- and preclinical-stage drug candidates with distinct mechanisms of action and novel chemical structures. All Synta drug candidates were discovered and developed internally. For more information, please see www.syntapharma.com.

Safe Harbor Statement

This media release may contain forward-looking statements about Synta Pharmaceuticals Corp. Such forward-looking statements can be identified by the use of forward-looking terminology such as "will", "would", "should", "expects", "anticipates", "intends", "plans", "believes", "may", "estimates", "predicts", "projects", or similar expressions intended to identify forward-looking statements. Such statements, including statements relating to the timing and progress of our clinical and preclinical programs, reflect our current views with respect to future events and are based on assumptions and subject to risks and uncertainties that could cause actual results to differ materially from those expressed or implied by such forward-looking statements, including those described in "Risk Factors" of our Form 10-K for the year ended December 31, 2006 as filed with the Securities and Exchange Commission. Synta undertakes no obligation to publicly update forward-looking statements, whether because of new information, future events or otherwise, except as required by law.