Data Presented From Two Phase 3 ERBITUX® Studies In First-Line Metastatic Colorectal Cancer Patients At Joint 15th European Cancer Organisation
According to a recent retrospective analysis of the pivotal Phase 3 CRYSTAL study, ERBITUX® (cetuximab), when added to FOLFIRI, was shown to increase median overall survival to 19.9 months in an intenttotreat (ITT) population of firstline metastatic colorectal cancer (mCRC) patients compared to 18.6 months in those receiving FOLFIRI alone (hazard ratio [HR] 0.878; 95% CI 0.774 0.995; p=0.042). In a subset of mCRC patients with wildtype Kras tumors, median overall survival was increased to 23.5 months in patients who received ERBITUX plus FOLFIRI compared to 20 months for those taking FOLFIRI alone (HR 0. 796; 95% CI 0.670 0.946; p=0.0094).
The retrospective CRYSTAL analysis was conducted as a result of an effort to increase the tissue ascertainment rate to determine the Kras status of patients tumors. The analysis included extended patient follow up of nearly 1.5 years and doubled the tissue ascertainment rate from 45% to 89%. These data are an update from the overall survival results from CRYSTAL that were published in the April 2009 issue of the New England Journal of Medicine.
The recently completed retrospective analysis from CRYSTAL, a multinational study conducted by Merck KGaA, Darmstadt, Germany, marks the first time an overall survival benefit has been demonstrated with an epidermal growth factor (EGFR)inhibitor in the firstline treatment of mCRC in an ITT patient population and in a Kras wildtype subset of patients. An ITT analysis considers all randomized patients in a clinical trial.
In the CRYSTAL trial, the following Grade 3 or 4 adverse events were reported in the April 2009 New England Journal of Medicine as being more frequent with ERBITUX plus FOLFIRI than FOLFIRI alone in the overall patient population skin reactions (which were grade 3 only) (in 19.7% vs. 0.2% of patients, p