Phase II trial of sorafenib (S) and erlotinib (E) in unresectable pancreas cancer (UPC): Final results and correlative findings.
191 Background: The MAP kinase pathway plays a central role in PC pathogenesis. Blockade of this pathway at multiple levels using S and E is attractive mechanistically. S also targets VEGF receptors. Evidence suggests that dual blockade of both EGFR and VEGF pathways has potential for additive, if not synergistic, effects. This phase II trial was designed to evaluate the efficacy of the combination of S and E in patients (pts) with UPC. An exploratory correlative study analyzing pre-treatment serum samples using a proteomic mass-spectrometry test (VeriStrat), previously shown to correlate with outcomes in lung cancer pts treated with E or the combination of E and S, was performed to evaluate the possible clinical utility of the test in pts with UPC. Methods: Pts with UPC received S 400mg daily along with E 150mg daily as primarily second-line therapy (first-line was allowed). Primary endpoint was 8-week progression free survival (PFS) rate. Pre-treatment serum sample analysis by proteomic test was done blinded to clinical and outcome data; the endpoints were PFS and overall survival (OS). Difference between groups was assessed using log-rank p values; hazard ratios (HR) were obtained from Cox proportional hazards models. Results: Thirty-seven pts received study drugs and were included in the survival analysis. Eight-week PFS rate 0.47 (95% CI 0.32-0.67) did not meet the primary endpoint of a rate of ≥ 0.70. Thirty two pts were included in the correlative analysis. VeriStrat “Good” pts had superior PFS and OS compared to VeriStrat “Poor” pts (Table). Conclusions: This study did not meet the primary endpoint and this drug combination will not be further pursued. In this small retrospective analysis the proteomic classification was significantly associated with clinical outcomes (PFS and OS), meriting further evaluation. This will include a companion study to an ongoing phase I study evaluating gemcitabine, erlotinib and dasatinib in UPC (NCT01660971). Clinical trial information: NCT00837876. [Table: see text]