Phase III study comparing cisplatin/vinorelbine plus cetuximab versus cisplatin/vinorelbine as first-line treatment for patients with epidermal growth factor (EGFR)-expressing advanced non-small cell lung cancer (NSCLC) (FLEX)

Abstract

7109 Background: Cisplatin plus vinorelbine is a commonly used regimen for first-line therapy of advanced NSCLC, achieving response rates of 20–30% and median survival times of 6 to 11 months (mths). An earlier phase II trial investigated cetuximab in combination with cisplatin and vinorelbine in this setting and found improved response rates in the cetuximab arm, warranting this larger phase III trial. Methods: Patients (pts) with EGFR-expressing advanced NSCLC (stage IIIB with documented malignant pleural effusion and stage IV) were randomized 1:1 either to Group A (cetuximab 400 mg/m2 initial dose then 250 mg/m2 weekly, cisplatin 80 mg/m2 on day 1, vinorelbine 30 mg/m2 on day 1 and 8) or to Group B (cisplatin and vinorelbine as before) for a maximum of 6 three-weekly cycles. Cetuximab was administered until progression or unacceptable toxicity. Primary endpoint is overall survival time; secondary endpoints are progression-free-survival, tumor response, disease control, safety, and quality of life. Enrollment of 1,100 pts was planned to show an increase of median survival time of 25% with 90% power. The Data Safety Monitoring Board (DSMB) performed an independent preplanned safety analysis from the first 370 pts. Patients were followed for a minimum of 6 weeks (2 cycles). Results: Since November 2004, 1,037 pts have been randomized, 689 are under treatment, and 348 pts have discontinued the study. Demographics of the first 370 pts reflected known advanced NSCLC characteristics: 91% stage IV, median age 60 yrs (31–79), 38% female, 80% ECOG PS 0/1, 52% adenocarcinoma, 30% squamous cell carcinoma; 29% never-smokers, 17% Asian. The ten most frequent adverse events were: nausea, neutropenia, vomiting, anorexia, fatigue, constipation, anemia, febrile neutropenia, rash, and diarrhoea. Conclusions: The trial continued after review of all relevant baseline and safety information from the first 370 pts. Recruitment is ongoing. [Table: see text]