Endostar combined with concurrent chemoradiotherapy versus concurrent chemoradiotherapy alone for locoregionally advanced nasopharyngeal carcinoma (LA-NPC): A phase III, prospective, randomised-controlled, multicenter clinical trial.

Abstract

6002 Background: Cisplatin-based concurrent chemoradiotherapy (CCRT) has long been regarded as standard treatment for LA-NPC. However, approximately 30% of patients still fail to obtain a satisfactory effect. Endostar (Rh-endostatin), an anti-angiogenesis inhibitor, is well-tolerated and has been reported as a promising complement to CCRT. This trial aimed to evaluate the efficacy and safety of adding Endostar to CCRT for LA-NPC. Methods: In this prospective, randomized phase III study, patients with LA-NPC (stage III-IVb, 7th edition) were enrolled at 6 centers in China, and randomly assigned (1:1) to receive Endostar plus CCRT (CCRT+E group, n=150) or CCRT alone (CCRT group, n=150). Endostar (7.5 mg/m2/day, days 1-10, 15 days/cycle) was given continuously intravenously for 5 cycles (3 concurrent from 5 days before radiotherapy, and 2 adjuvant from the first day after the completion of radiotherapy). The primary endpoint was the progress-free survival (PFS) rate. The secondary endpoints included overall survival (OS), distant metastasis-free survival (DMFS), local-regional relapse-free survival (LRRFS), the rate of complete response (CR) at 3 months after RT, and safety. Results: Between November 2016 and July 2020, 300 patients with LA-NPC were randomized (CCRT+E group, 150; CCRT group, 150). As of the data cutoff (December 2023), the median follow-up was 66 months. Intention-to-treat analysis showed that patients in the CCRT+E group achieved better CR rate at 3 months after RT (90.0% vs 80.7%, P=0.022). The 3-year PFS was 84.8% in the CCRT+E group, and 75.1% in the CCRT group (HR, 0.544; 95% CI, 0.336-0.879; Plog-rank=0.011). The 3-year OS was 89.2% vs. 85.3% (HR, 0.595; 95% CI, 0.361-0.982; Plog-rank=0.039). The 3-year DMFS was 89.7% vs. 80.5% (HR, 0.468; 95% CI, 0.266-0.821; Plog-rank=0.007). The 3-year LRRFS was 91.5% vs. 90.8% (HR, 0.808; 95% CI, 0.407-1.604; Plog-rank=0.541). Patients in the CCRT+E group and in the CCRT group had similar Grade 3-4 acute and late toxicity profile (61.7% vs. 65.3%, p=0.519 and 8.0% vs.7.3%, p=0.815). Conclusions: The addition of Endostar to standard CCRT significantly improved the 3-year PFS of LA-NPC patients with good safety profile. Clinical trial information: NCT02907710 .