Disease Control as a Predictor of Survival with Gefitinib and Docetaxel in a Phase III Study (V-15-32) in Advanced Non-small Cell Lung Cancer Patients

Abstract

This post hoc analysis investigated the relationship between tumor response and overall survival (OS) in pretreated advanced non-small cell lung cancer (NSCLC). We conducted landmark survival analyses of V-15-32, a phase III study comparing gefitinib with docetaxel in pretreated advanced NSCLC. Best response at weeks 8, 12, 16, and 20, and visit response at week 4, were evaluated. Disease control (DC; complete response [CR], partial response [PR], or stable disease) was a better predictor of OS than CR/PR at all time points. The strongest predictor of OS for both gefitinib and docetaxel was DC at week 8 (hazard ratio [HR] DC versus non-DC: 0.30, 95% confidence interval [CI] 0.20-0.45, p < 0.001 for both treatments). DC at week 4 was also associated with longer survival compared with non-DC for both treatments (HR 0.33, 95% CI 0.23-0.49, p < 0.001 for gefitinib; HR 0.30, 95% CI 0.19-0.47, p < 0.001 for docetaxel). DC is a better predictor of OS with gefitinib and docetaxel than CR/PR in advanced pretreated NSCLC, with a best response of DC at week 8 the strongest predictor.