Camrelizumab combined with capecitabine as maintenance therapy for metastatic nasopharyngeal carcinoma: A phase II single-arm clinical trial.

e18016 Background: Metastasis is the main cause of death in nasopharyngeal carcinoma (NPC). The current first-line treatment for metastatic NPC involves gemcitabine, cisplatin, and camrelizumab followed by camrelizumab maintenance. This phase II trial evaluates the efficacy and safety of camrelizumab combined with capecitabine as a novel maintenance therapy strategy after systemic treatment. Methods: This study enrolled 20 patients with metastatic nasopharyngeal carcinoma, comprising 11 with synchronous metastases and 9 with asynchronous (post-treatment) metastases. All patients received systemic therapy with camrelizumab (200mg d1) plus gemcitabine (1000 mg/m² d1 and 8) and cisplatin (80 mg/m² d1) intravenously every 3 weeks (4-6 cycles), followed by maintenance therapy with camrelizumab (200mg d1) plus capecitabine (1000 mg/m² bid d1–14). The primary endpoint was the 1-year progression-free survival (PFS) rate. Secondary endpoints included the 18-/24-month PFS rate, 12-/18-/24 month overall survival (OS) rate, and the incidence of adverse events. Results: As of December 31, 2025, 20 patients were enrolled, with a median age of 41 years (range: 26–62). Among them, 15 were male and 5 were female; 8 had a history of smoking; 18 tested positive for EB virus after metastasis; 6 patients underwent induction chemotherapy, and 9 underwent definitive radiotherapy prior to the development of metastasis. Two patients received 5 cycles of systemic therapy, while the remaining 18 completed 6 cycles. Additionally, liver metastasis was observed in 10 patients (50%), bone metastasis in 9 (45%), and lung metastasis in 6 (30%). All patients were alive, and the 12-month PFS rate (systemic therapy + maintenance therapy) was 81.48%. The median survival was not yet reached. The objective response rate (ORR) was 100%. Treatment-emergent adverse events (TEAEs) of any grade occurred in all 20 patients, with all patients experiencing at least one grade ≥3 event. The most common grade ≥3 TEAEs included anemia (55%), neutropenia (55%), thrombocytopenia (25%), elevated aspartate aminotransferase (5%), and diarrhea (5%). Once maintenance therapy is started, the adverse reactions are significantly alleviated. Conclusions: Camrelizumab combined with capecitabine as maintenance therapy effectively prolongs survival time in patients with metastatic nasopharyngeal carcinoma, demonstrating favorable efficacy and safety. Enrollment is ongoing, and further validation of specific data is awaited. Clinical trial information: ChiCTR2500111883.