Evaluating neoadjuvant intravesical mitomycin C in NMIBC: A phase III randomized clinical trial.

• DOI: 10.1200/jco.2025.43.5_suppl.803
• Publication Date: 2025-02-18T14:32:56Z
• Authors: Roberto Contieri; Alberto Saita; Marco Paciotti; Alessandro Uleri; Pier Paolo Avolio; Vittorio Fasulo; Ludovica Cella; Stefano Mancon; Federica Sordelli; Giuseppe Garofano; Paola Arena; Chiara Pozzi; Miriam Cieri; Piergiuseppe Colombo; NicolòMaria Buffi; Giovanni Lughezzani; Paolo Casale; Maria Rescigno; Massimo Lazzeri; Rodolfo Hurle
• Keywords: Mitomycin C

803 Background: The primary treatment for non-muscle invasive bladder cancer (NMIBC) is transurethral resection (TUR), often followed by adjuvant intravesical therapies. Given the variable response to therapy, enhancing its efficacy critical reducing recurrence and progression MIBC. Recent studies have shown that MMC induces immunogenic cell death, suggesting potential in effectiveness of other therapies, such as BCG, activating acquired immunity. This study aimed evaluate safety neoadjuvant patients with NMIBC. Methods: a prospective, phase III randomized clinical trial or recurrent BC who had not received therapy between May 2022 June 2024 (EudraCT 2021-003751-42; ICH-013). Patients were 1:1 either arm (neoA) standard (StA). In two weeks preceding scheduled TURBT (day 0), neoA (40 mg/40 ml) on days -14 -7, along cystoscopy cold-cup biopsy day -14. Clinical decisions regarding follow-up (FU) schedules both groups based tumor histology according European Association Urology (EAU) guidelines. endpoint was safety, rate BC. MIBC pT0 excluded from survival analyses. Results: A total 63 included: 31 (49%) StA group 32 (51%) group. homogeneous pathological characteristics.In group, 8 adverse events (AEs) reported 5 (14%), all mild (Grade 1 2). Following TUR, 26 AEs grade 2 observed 16 (50%) 24 14 (45%) no significant differences (p=0.6).In TaLG, 9 TaHG, 3 T1HG, CIS, benign findings. No complete ablation occurred, only cases showing reduced size. 17 6 T2 tumors. After median FU 14.5 months, 4 recurred. Only one patient, progressed 12-month recurrence-free (RFS) 91% (95% CI: 68-98) 84% 62-94) statistically difference (log-rank test p=0.8). Conclusions: Neoadjuvant showed favorable tolerability profile. Although RFS found arms, larger cohort longer are needed definitive conclusions MMC's oncological efficacy. upcoming analysis BCG subgroup will further clarify role