Adjuvant nivolumab in high-risk muscle-invasive urothelial carcinoma: Real-world evidence from the SOGUG-NIADY study of the Spanish Oncology Genitourinary Group (SOGUG).

Abstract

4606 Background: Adjuvant nivolumab significantly improved disease-free survival (DFS) in patients (pts) with high-risk muscle-invasive urothelial carcinoma (MIUC) after radical surgery in the phase III CheckMate-274 trial. Based on these results, since august 2023, the Spanish National Health System reimburses postoperative nivolumab in high-risk, positive programmed death ligand 1 (PDL1) MIUC. The aim of the PrInCIS-NIADY study was to assess the effectiveness and safety of adjuvant nivolumab in real-world clinical practice after its approval in Spain. Methods: PrInCIS is a nationwide multicentre, non-interventional epidemiological study with retrospective patient inclusion and prospective follow-up. The NIADY cohort included pts with high-risk PDL1+ MIUC treated with adjuvant nivolumab in routine practice, was conducted across 65 hospitals belonging to the Spanish Oncology Genitourinary Group (SOGUG) in 16 Spanish regions. Baseline characteristics, treatment patterns, safety, and outcomes were analysed and compared against CheckMate-274. Results: A total of 395 evaluable pts were included, 95.7% were PD-L1 positive. Median age was 69.5 years, (74.9% aged ≥65 years); 91.4% had bladder cancer and 8.6% had upper tract disease. Predominant histology was urothelial carcinoma (79.2%). 51.2% pts received neoadjuvant platinum-based chemotherapy (NAChT) (48.9% cisplatin vs. 2.3% carboplatin) (Table). With a median follow-up of 13 months, 27.3% of pts had disease recurrence. Treatment after recurrence was platinum-based ChT in 8.8% and enfortumab vedotin in 6.6% of pts. Median DFS and overall survival (OS) were not reached. The estimated 18-month DFS and OS probability were 65.6% and 78.3% respectively. Nivolumab was well-tolerated: Treatment delays or dose reductions occurred in 37.3% of pts. Most common (>10%) grade 1-2 immune-related adverse events were fatigue, pruritus and diarrhea, while grade 3–4 toxicity was infrequent (>1%), mainly consisting in hepatic enzyme and creatinine elevation. Conclusions: Outcomes and effectiveness of adjuvant nivolumab in this large Spanish real-world cohort were consistent with the Checkmate-274 results, with a manageable safety profile despite an older population. In spite of short-term follow-up, these findings externally validate the results of the pivotal trial reinforcing the role of adjuvant nivolumab in daily clinical practice for high-risk MIUC. Patient characteristics. Characteristics CHECKMATE-274 (N=353) NIADY (N=395) Age. Mean (range)-yr 65.3 (30-92) 69.5 (35-88) Sex. Male / Female 75.1 / 29.9 % 81.8 / 19.2 % ECOG 0-1 / >2 98 / 2 % 96.7 / 3.3 % Bladder/Upper tract 79 / 21% 91.4 / 8.6 % Pure urothelial / mixed histology 59.7 / 40.3 % 79.2 / 20.7 % NAChT cisplatin / carboplatin 43.3 / NA % 48.9 / 2.3 % pT2-4a N0 52.2 % 64.3 % pT4b o N+ 47.3 % 35.7 % PDL1+ >=1% 39.7 % 95.7 %