8:05AM Amgen announces overall survival results for Vectibix in first-line metastatic colorectal cancer (AMGN) 52.12 : Co announces that the Phase 3 PRIME "203" trial evaluating Vectibix administered in combination with FOLFOX as a first-line treatment of metastatic colorectal cancer failed to meet a secondary endpoint of overall survival. Earlier this year, it was announced that the trial met its primary endpoint by significantly prolonging progression-free survival in the first-line treatment of patients with KRAS wild-type mCRC. Overall survival appeared to be reduced in patients with KRAS mutant tumors receiving Vectibix. Although not statistically significant, this result emphasizes the importance, as described in product labeling, of ensuring that patients receiving Vectibix do not bear tumors containing KRAS mutations. Overall, the adverse event profile was as anticipated for an anti-EGFR antibody in combination with oxaliplatin-based chemotherapy, including known events such as rash, diarrhea and hypomagnesemia. Vectibix-related grade 3 infusion reactions were reported for two patients. Originally designed to compare the treatment effect in the overall population, the study was amended to analyze outcomes with respect to the presence or absence of activating mutations in KRAS in the tumor itself. Tumor KRAS status was ascertained in more than 90%of the 1,183 patients enrolled in the trial.