DUBLIN, Calif., Sept. 21, 2012 (GLOBE NEWSWIRE) -- Astex Pharmaceuticals, Inc. (Nasdaq:ASTX), a pharmaceutical company dedicated to the discovery and development of novel small molecule therapeutics, today announced that clinical development of amuvatinib (MP-470), a multi-targeted tyrosine kinase inhibitor that inhibits the mutant forms of c-Kit and PDGFR alpha and disrupts DNA repair likely through suppression of homologous recombination protein Rad51, has been discontinued. Amuvatinib was being investigated in the Phase 2 ESCAPE (Tr Eatment of Small Cell lung cancer with Amuvatinib in combination with Platinum Etoposide) study. The study used a Simon 2-stage design with the primary objective in stage 1 of excluding the statistical probability with 90% confidence that the drug has less than 10% response rate in platinum refractory small cell lung cancer (SCLC) patients. Response evaluation by RECIST criteria showed 2 partial responses in the 21 evaluable patients of stage 1 (9.5% Response Rate). No new safety issues were identified, and biological markers studies are ongoing. There were several patients with prolonged stable disease. The results will be presented in a future scientific meeting. "This clinical proof of concept (cPOC) amuvatinib trial was designed in two parts to define clinical activity and confirm clinical benefit and safety in combination with chemotherapy," said James S.J. Manuso, PhD, chairman and chief executive officer. "We have decided to end the clinical development of amuvatinib despite the favorable safety and preliminary clinical activity we observed in the first stage of this Phase 2 trial and in the earlier Phase 1b trial in combination platinum-etoposide based chemotherapy. We will consider the possibility of licensing the compound to any partners who would be interested in its further development." "Amuvatinib's performance in the clinic was promising in the Phase 1b combination trial with DNA damaging agents," said Mohammad Azab, MD, chief medical officer. "There is no effective treatment for SCLC patients with truly platinum-refractory disease similar to the patients enrolled in this study. While some clinical activity was observed, the ESCAPE study response rate in stage 1 fell short of fully meeting our pre-specified primary endpoint. Consistent with our corporate strategy to move into advanced clinical stages only those agents that meet our pre-specified primary endpoints in the cPOC stage, we decided to discontinue the internal development of this program."