NAPOLI-1 phase 3 study of liposomal irinotecan in metastatic pancreatic cancer: final overall survival analysis and characteristics of long-term survivors.

Abstract

BACKGROUND: Liposomal irinotecan (nal-IRI) plus 5-fluorouracil and leucovorin (5-FU/LV) is approved for patients with metastatic pancreatic ductal adenocarcinoma (mPDAC) previously treated with gemcitabine-based therapy. This approval was based on significantly improved median overall survival compared with 5-FU/LV alone (6.1 vs 4.2 months; hazard ratio [HR], 0.67) in the global phase 3 NAPOLI-1 trial. Here, we report the final survival analysis and baseline characteristics associated with long-term survivors (survival of ?1 year) in the NAPOLI-1 trial.

PATIENTS AND METHODS: Patients with mPDAC were randomised to receive nal-IRI + 5-FU/LV (n = 117), nal-IRI (n = 151), or 5-FU/LV (n = 149) for the first 4 weeks of 6-week cycles. Baseline characteristics and efficacy in the overall population were compared with those in patients who survived ?1 year. Through 16th November 2015, 382 overall survival events had occurred.

RESULTS: The overall survival advantage for nal-IRI+5-FU/LV vs 5-FU/LV was maintained from the original nanoliposomal irinotecan with fluorouracil and folinic acid in metastatic pancreatic cancer after previous gemcitabine-based therapy (NAPOLI-1) analysis (6.2 vs 4.2 months, respectively; HR, 0.75; 95% confidence interval: 0.57-0.99). Median progression-free survival, objective response rate and disease control rate also favoured nal-IRI+5-FU/LV therapy. Estimated one-year overall survival rates were 26% with nal-IRI+5-FU/LV and 16% with 5-FU/LV. Baseline characteristics associated with long-term survival in the nal-IRI+5-FU/LV arm were Karnofsky performance status ?90, age ?65 years, lower CA19-9 levels, neutrophil-to-lymphocyte ratio ?5 and no liver metastases. No new safety concerns were detected.

CONCLUSIONS: The survival benefits of nal-IRI+5-FU/LV versus 5-FU/LV were maintained over an extended follow-up, and prognostic markers of survival ?1 year were identified.