A Randomized, Multicenter, Phase 2 Trial of Camrelizumab With or Without Metastasis-directed Stereotactic Body Radiation Therapy in Recurrent or Metastatic Nasopharyngeal Carcinoma.

Abstract

To investigate the efficacy of metastasis-directed therapy (MDT) when added to camrelizumab (Cam) in patients with recurrent or metastatic nasopharyngeal carcinoma (R/M-NPC). We conducted a randomized, controlled, multicenter, phase 2 trial in 3 centers from China (NCT04830267). Patients with R/M-NPC, without prior exposure to immunotherapy, who presented with ≥2 lesions, and at least 1 measurable lesion were randomized 1:1 to either Cam alone or Cam plus MDT (Cam+MDT). Patients randomized to the MDT group must have 1 lesion that is amendable to stereotactic body radiation therapy (SBRT) prescribed to 27 Gy in 3 fractions every other day. The primary endpoint was objective response rate (ORR) of unirradiated lesions using Response Evaluation Criteria in Solid Tumors v1.1. Between April 2021 and August 2023, 39 patients were randomly assigned to receive either Cam (n = 20) or Cam+MDT (n = 19). In total, 17 out of 39 (43.6%) patients had oligometastatic disease (≤3 lesions), 18 out of 39 (46.2%) had liver involvement, and 3 out of 39 (7.7%) had locoregional recurrent disease. ORR of unirradiated lesions did not differ between the treatment groups (26.3% [Cam+MDT] vs 30.0% [Cam], P = 1.0). The disease control rate of unirradiated lesions was 73.7% in the Cam+MDT group compared with 60.0% in the Cam group (P = .571). After a median follow-up of 25.8 months, median progression-free survival was 9.3 (95% CI, 6.2-not reached [NR]) months in the Cam+MDT group and 8.8 (95% CI, 3.3-NR) months in the Cam group (P = .750). Exploratory analyses suggested a longer overall survival (OS) with Cam+MDT for patients with >3 lesions (HR, 0.23; 95% CI, 0.07-0.77; P = .009). G3 and above adverse events were comparable between the treatment groups (15.8% [Cam+MDT] vs 20.0% [Cam]). The overall rate of capillary proliferation was 17.9% (7/39) for the trial. Our study did not meet its primary endpoint of superior ORR of unirradiated lesions with the addition of MDT to Cam in patients with R/M-NPC.