Astex Reports Positive First Data Showing Early Combination Treatment of HSP90 Inhibitor AT13387 with Targeted Agents

Astex Pharmaceuticals, Inc. ASTX, a pharmaceutical company dedicated to the discovery and development of novel small molecule therapeutics, today announced data demonstrating for the first time that early treatment with AT13387, a second generation, fully synthetic HSP90 inhibitor, in combination with targeted therapy delays the emergence of resistance. These results were presented at the 8th World Congress of Melanoma July 17 to 20 in Hamburg, Germany. In a preclinical model of mutant BRAF melanoma, animals were treated with vemurafenib alone or vemurafenib in combination with AT13387. After 2 to 4 months of continued treatment, tumor-bearing mice treated with vemurafenib alone showed the emergence of resistance and tumor regrowth while animals treated with the combination of vemurafenib and AT13387 did not show such regrowth. In addition, tumors that became resistant to vemurafenib alone were still sensitive to AT13387 treatment. The poster presentation was among six posters awarded best poster award at the conference. These data support the early use of AT13387 in combination with targeted therapy to delay the emergence of resistance and prolong the duration of response and progression-free time. A clinical study of the combination of AT13387 with both BRAF and MEK inhibitors is being planned. About See full press release