663P Camrelizumab plus apatinib in patients with recurrent or metastatic nasopharyngeal carcinoma failing first-line therapy: An open-label, single-arm, phase II study

Immune-checkpoint inhibitor (ICI) combined with antiangiogenic therapy have the potential for synergistic activity through modulation of the microenvironment. We report the activity and safety of camrelizumab plus apatinib in patients with recurrent or metastatic nasopharyngeal carcinoma (NPC) who were refractory to at least one line of systemic therapy. This single-arm, phase II study enrolled patients with recurrent or metastatic NPC (nonkeratinizing carcinoma) who were refractory to at least one line of systemic therapy and treatment-naïve to ICI. Patients received camrelizumab 200 mg every 3 weeks and apatinib 250 mg once per day. The primary end point was objective response rate (ORR) assessed by independent radiologists per RECIST version 1.1. Key secondary end points included progression-free survival (PFS), duration of response (DoR), disease control rate (DCR), and safety. Between Oct 14, 2020, and Dec 23, 2021, 71 patients were assessed for eligibility, of whom 58 patients were enrolled. All patients (mean [SD] age: 48 [9.59] years; 79.3% male) were included in the efficacy and safety analysis. The ORR was 65.5% (95% CI, 51.9-77.5) and the DCR was 86.2% (95% CI, 74.6-93.9). The median DoR was not reached and a median PFS was 10.4 months (95% CI, 7.2-13.6), with a median follow-up duration of 12.4 months (IQR, 5.6-13.2). Treatment-related adverse events (TRAEs) of grade 3 or higher were reported in 34 (58.6%) patients, mainly hypertension (19.0%), nasopharyngeal necrosis (15.5%), headache (12.1%), and creatine phosphokinase elevation (10.3%). 16 (27.6%) patients discontinued apatinib treatment ahead of progression because of unbearable TRAEs, and the most common one was nasopharyngeal necrosis (9/16, 56.3%). Nasopharyngeal recurrent lesion (odd ratio = 5.3, p=0.014) and courses of nasopharyngeal radiotherapy (p=0.015) were significantly positively correlated with nasopharyngeal necrosi. Camrelizumab plus apatinib had promising antitumor activity and manageable toxicities in recurrent or metastatic NPC. Larger randomized controlled trials are warranted to validate our findings.