Phase 2 trial of liposomal irinotecan plus nimotuzumab for ICI-refractory recurrent of metastatic nasopharyngeal carcinoma

Patients with recurrent of metastatic nasopharyngeald carcinoma (R/M NPC) who progress after immune checkpoint inhibitor (ICI) therapy have limited treatment options and poor outcomes. A phase 2 trial at Sun Yat-sen University Cancer Center (Guangzhou, China) evaluated the combination of liposomal irinotecan plus nimotuzumab for patients with EGFR-positive, ICI-refractory R/M NPC. Patients received up to eight cycles of liposomal irinotecah 70 mg/m² plus nimotuzumab 400 mg every 2 weeks. The primary endpoint was objective response rate (ORR). Thirty-six pretreated patients were enrolled, of whom 12 (33.3%) had received three or more prior lines of therapy for advanced disease. Thirteen of 36 patients achieved an objective response (ORR 36.1%; 95 CI 20.8-53.8) and 22 patients (61.1%) achieved disease control. Median progression-free survival was 3.0 months (95% CI 2.2-4.1) and median duration of response was 2.3 months (1.5-3.1). After a median follow-up of 22.0 months, the median overall survival was 14.1 months (95% CI 8.7-NE). Grade 3 or 4 treatment-related adverse events occurred in eight of 36 patients (22.6%); there were no treatment-related deaths. In a post-hoc exploratory analysis, early decline in plasma Epstein-Barr virus DNA was associated with higher ORR. The authors conclude that liposomal irinotecan plus nimotuzumab showed preliminary antitumor activity and manageable safety in heavily pretreated patients with ICI-refractory R/M NPC.