Purpose: To evaluate the activity and safety of nivolumab with nab-paclitaxel as neoadjuvant therapy, followed by radical cystectomy (RC) and postsurgical adjuvant nivolumab in patients with muscle-invasive bladder cancer (MIBC).
Patients and methods: Eligible patients had an Eastern Cooperative Oncology Group performance status of ≤1 and a T2-4aN0-1M0 stage with >50% urothelial carcinoma histology and were ineligible for or refused cisplatin-based chemotherapy. Patients received four cycles of nivolumab 360 mg once every 3 weeks + nab-paclitaxel 125 mg/m2 once on days 1 and 8, every 3 weeks, followed by RC, and then adjuvant nivolumab 360 mg once every 3 weeks × 13 cycles. The primary end point was the pathologic complete response (CR) rate (ypT0N0). Secondary end points were major pathologic response (ypT≤1N0), safety, event-free survival (EFS), and overall survival.
Results: Thirty-one patients were enrolled from December 2021 to June 2023; 19 (61.3%) had a cT2 stage, two (6.5%) had N1 stage, and 16 (51.6%) had a variant histology. Five patients (16.1%) received less than four full courses of neoadjuvant treatment because of treatment-related adverse events (TRAEs). Grade 3/4 TRAEs occurred in eight patients (25.8%). Twenty-eight patients underwent RC, and three refused RC after evidence of clinical CR and received a redo transurethral resection of the bladder tumor (reTURBT). The trial met its primary end point: 10 patients (32.3%; 95% CI, 16.7 to 51.4) achieved an ypT0N0 response. By including those who underwent reTURBT, 22 (70.9%; 95% CI, 55 to 87) achieved an ypT≤1N0-x response. After a median follow-up of 12 months (range, 5-22), two patients had a disease relapse after surgery. The 12-month EFS was 89.8% (95% CI, 79.5 to 100).
Conclusion: To our knowledge, the first results from NURE-Combo trial suggest that this combination could expand the therapeutic opportunities of immune-chemotherapy in patients with MIBC.
Trial registration: ClinicalTrials.gov NCT04876313.