Docetaxel and erlotinib are registered second-line treatments for wild-type EGFR NSCLC. Previous studies suggested a predictive value of the VeriStrat test in second-line therapy of NSCLC, classifying patients as either VeriStrat good or VeriStrat poor. EMPHASIS-lung aimed at exploring this predictive effect in patients with squamous cell NSCLC. The trial closed prematurely because of low accrual and results from other trials. Our analysis includes an exploratory combined analysis with results from the PROSE trial.
EMPHASIS-lung was a randomized phase III multicenter trial exploring the differential effect of second-line erlotinib versus docetaxel on progression-free survival (PFS) in VeriStrat good versus VeriStrat poor patients with squamous cell NSCLC.
A total of 80 patients were randomized, with 72.5% categorized as VeriStrat good. Patient characteristics were balanced between VeriStrat status and treatment groups. The median PFS times with docetaxel and erlotinib treatment in the VeriStrat good cohort were 4.1 and 1.6 months, respectively, versus 1.9 and 2.1 months, respectively, in the VeriStrat poor cohort. The median overall survival (OS) times with docetaxel and erlotinib treatment in the VeriStrat good cohort were 7.8 and 8.4 months, respectively, and 4.4 and 5.2 months, respectively, in the VeriStrat poor cohort. An additional exploratory analysis was performed; in it, 47 patients from the squamous cell subgroup of PROSE were included in a combined analysis, contributing with 45 PFS and 41 OS events.
The final analysis of EMPHASIS-lung did not show a differential effect on PFS for erlotinib versus docetaxel stratified by VeriStrat status. Similarly, in the combined analysis, no significant treatment by VeriStrat status interaction was observed (interaction p = 0.24 for PFS and 0.45 for OS, stratified by study).