3567^ Background: Pmab is a fully human anti epidermal growth factor receptor (EGFR) monoclonal antibody. The primary analysis of this study (PRIME) demonstrated that pmab + FOLFOX4 significantly improved progression free survival (PFS) vs FOLFOX4 alone for 1st line mCRC in patients (pts) with wild-type (WT) KRAS.
METHODS
Pts were randomized 1:1 to pmab 6.0 mg/kg Q2W + FOLFOX4 (Arm 1) or FOLFOX4 alone (Arm 2). Pts had no prior chemotherapy for mCRC, ECOG ≤2, and tumor tissue for biomarker testing. Randomization was stratified by geographic region and ECOG ≤1 vs 2. The primary endpoint was PFS. Secondary endpoints included overall survival (OS) and safety. KRAS status was determined retrospectively using a validated testing kit (DxS, Manchester, UK) by a blinded central lab prior to the primary analysis. Here we present the prespecified descriptive analysis of efficacy by ECOG PS based on the primary OS analysis.
RESULTS
From 8/06 to 2/08, 1183 pts were randomized and received tx: 593 Arm 1, 590 Arm 2. In an evaluation of the effect of covariates on tx outcomes in the primary analysis using the Quantitative Interaction Test, the only significant treatment by covariate interaction was observed for ECOG PS. A significant difference between tx effects in pts with ECOG 0/1 and ECOG 2 was observed for both PFS (p = 0.003) and OS (p = 0.037). Efficacy results by ECOG PS are shown (Table).
CONCLUSIONS
In pts with WT KRAS and ECOG 0/1, pmab improved OS and PFS when added to FOLFOX4. In pts with WT KRAS and ECOG 2, shortened OS and PFS were observed in pts receiving pmab + FOLFOX4. Detailed results, including safety data, will be presented. [Table: see text].