Randomized phase II study of vandetanib (VAN) alone or in combination with carboplatin and paclitaxel (CP) as first-line treatment for advanced non-small cell lung cancer (NSCLC)

Abstract

7544 Background: VAN (ZD6474) is a once-daily oral agent that selectively inhibits VEGFR, EGFR and RET signaling. This randomized phase II trial investigated VAN alone or in combination with CP vs CP. Methods: Eligible patients (pts) had previously untreated locally advanced or metastatic (IIIB-IV) NSCLC. The primary objective was to determine whether VAN (300 mg/day) ± CP (C, target AUCss = 6 mg/ml·min; P; 200 mg/m2 iv) prolonged progression-free survival (PFS) vs CP (75% power to detect 30% prolongation; 1-sided P=0.2). An initial run-in phase had established VAN 300 mg/day as an appropriate dose to be given with CP. Results: A total of 181 pts (median age 61 yrs, range 27–83) received VAN (n=73), VAN + CP (n=56) or CP (n=52). The primary objective was met, with VAN + CP prolonging PFS vs CP (HR = 0.76, 95% CI 0.50–1.15; P=0.098): median PFS = 24 wks (VAN + CP) and 23 wks (CP). The VAN monotherapy arm was stopped early after a planned interim PFS analysis met the criterion for discontinuation (HR > 1.33 vs CP). The objective response rates were 32%, 25% and 7% for VAN + CP, CP and VAN, respectively. Overall survival (OS), a secondary endpoint, was not significantly different between pts receiving VAN + CP or CP (HR = 1.07, 95% CI 0.63–1.81; P=0.595). Exploratory subgroup analyses suggest advantages in PFS and OS for VAN + CP vs CP for the 56 female pts. There was a higher incidence of some adverse events with VAN + CP vs CP, including rash (64% vs 33%), diarrhea (53% vs 32%), asymptomatic QTc-related events (22% vs 4%) and hypertension (32% vs 4%). Pts receiving VAN + CP, including 7 who entered with CNS metastases and 11 with squamous histology, did not experience any intracranial bleeding, or hemoptysis of CTC grade 2 or higher. A biomarker analysis, including circulating endothelial cells and 35 plasma angiogenic factors and cytokines, suggests several potential markers predictive of clinical outcome and will be reported separately. Conclusions: In this randomized phase II trial of 1st-line advanced NSCLC, VAN + CP met the primary endpoint of prolonging PFS vs CP alone but did not provide a detectable survival advantage. No significant financial relationships to disclose.