PARIS, Dec. 2, 2013 (GLOBE NEWSWIRE) -- AB Science SA (NYSE Euronext - FR0010557264 - AB), a pharmaceutical company specialized in research, development and marketing of protein kinase inhibitors (PKIs), announces the initiation of a phase 3 study to evaluate the safety and efficacy of masitinib in combination with FOLFIRI in patients with metastatic colorectal cancer (mCRC) in first relapse. This is an international, multicenter, randomized, double blind, placebo-controlled, 2-parallel group, phase 3 study to evaluate the efficacy and safety of masitinib in combination with FOLFIRI (irinotecan, 5-fluorouracil and folinic acid) for second-line treatment of patients with metastatic colorectal cancer. The study will measure overall survival as a primary efficacy criterion. One of the objectives of this phase 3 study in colorectal cancer will be to identify those subgroups that best respond to masitinib, similar to the prospective subgroup analyses previously reported in the pancreatic cancer phase 3 study. The phase 3 study has been authorized by competent authorities. The decision to move to phase 3 follows encouraging preliminary results from phase 2. Phase 2 has recruited 46 patients and tested three combinations of masitinib with standard-of-care chemotherapies including FOLFIRI, FOLFOX, and gemcitabine. The masitinib plus FOLFIRI combination has proved to be the most efficient and best tolerated one. Median overall survival in the masitinib plus FOLFIRI treatment-arm reached 14.5 months, which compares favorably to published results for FOLFIRI as a single agent at 12.5 months in patients with wild-type KRAS and 11.1 months in patients with mutant KRAS [Peeters et al. 2010]. These data, although preliminary, are important since it is the third time an extended survival has been observed in clinical studies with masitinib as compared to standard-of-care. The first time was in imatinib-resistant GIST, with masitinib generating an additional 12 months median overall survival versus sunitinib. The second time was in first-line treatment of pancreatic cancer, with two subpopulations having poor prognosis (i.e. patients with pain and patients with an aggressive genomic biomarker that flags a poor immune response) respectively reporting an additional median overall survival of 3 and 8 months for masitinib plus gemcitabine with respect to gemcitabine alone. The third time is in metastatic colorectal cancer with the combination masitinib plus FOLFIRI.