Vandetanib Versus Placebo in Patients With Advanced Non-Small-Cell Lung Cancer After Prior Therapy With an Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor: A Randomized, Double-Blind Phase III Trial (ZEPHYR)

Purpose Vandetanib is a once-daily oral inhibitor of vascular endothelial growth factor receptor, epidermal growth factor receptor (EGFR), and RET signaling. This placebo-controlled trial assessed whether vandetanib conferred an overall survival benefit in patients with advanced non-small-cell lung cancer (NSCLC) after prior treatment with an EGFR tyrosine kinase inhibitor and one or two chemotherapy regimens. Patients and Methods Eligible patients were randomly assigned 2:1 to receive vandetanib 300 mg/d or placebo until disease progression or unacceptable toxicity. The primary objective was to compare the outcomes between the two arms with respect to overall survival. Results Overall, 924 patients received vandetanib (n = 617) or placebo (n = 307). No significant increase in overall survival was detected in the vandetanib cohort compared with placebo (hazard ratio = 0.95; 95.2% CI, 0.81 to 1.11; P = .527); median overall survival was 8.5 months versus 7.8 months for vandetanib and placebo patients, respectively. Statistically significant advantages favoring vandetanib were observed for progression-free survival (hazard ratio = 0.63; P < .001) and objective response rate (2.6% v 0.7%; P = .028). Postprogression therapy was balanced across the cohorts in both number and type. Adverse events were generally consistent with previous NSCLC studies of vandetanib 300 mg; common events occurring with a greater frequency in the vandetanib arm versus placebo included diarrhea (46% v 11%), rash (42% v 11%), and hypertension (26% v 3%). Conclusion The study did not demonstrate an overall survival benefit for vandetanib versus placebo. There was a higher incidence of some adverse events with vandetanib.