Academic In-Depth Interpretation
Editor’s Note: During the 2026 European Association of Urology (EAU) Congress, Prof. Saad M.A. from the Department of Medical Oncology at the Mohammed V Military Teaching Hospital, Rabat, Morocco, presented a systematic review and reconstructed Individual Patient Data (IPD) meta-analysis. The study evaluated the clinical value of Bacillus Calmette-Guérin (BCG) combined with Immune Checkpoint Inhibitors (ICIs) in BCG-naive patients with high-risk Non-Muscle-Invasive Bladder Cancer (NMIBC).
01 Background: Challenges in Standard of Care for High-Risk NMIBC
For decades, Transurethral Resection of Bladder Tumor (TURBT) followed by adjuvant BCG instillation has remained the Standard of Care (SoC) for BCG-naive, high-risk NMIBC. However, up to 30% of patients remain refractory or show an inadequate response to this approach. To improve outcomes, clinical trials have explored intensification strategies by combining BCG with systemic ICIs. Given the varying results across different studies, a high-level evidence synthesis via meta-analysis was necessitated.
02 Methodology: IPD Analysis Based on Three Major Clinical Trials
This meta-analysis utilized reconstructed Individual Patient Data (IPD) from 2,590 patients enrolled in three pivotal clinical trials: CREST, POTOMAC, and ALBAN. The research aimed to comprehensively assess the efficacy and tolerability of adding systemic ICIs to the standard BCG regimen.
03 Efficacy Assessment: Induction plus Maintenance Significantly Improves EFS
The data indicated that the addition of systemic ICIs to the BCG regimen significantly improved Event-Free Survival (EFS). • Combination Advantage: The most significant EFS benefit was observed when ICIs were administered during both the induction and maintenance phases of BCG therapy, yielding a Hazard Ratio (HR) of 0.77. • Impact of Treatment Duration: Notably, this survival advantage disappeared entirely when ICIs were added only during the BCG induction phase. This suggests that the duration of immunotherapy is a critical factor in the success of intensification regimens for NMIBC.
04 Subgroup Focus: Superior Benefits in Carcinoma In Situ (CIS)
Subgroup analysis by pathological type revealed that patients with Carcinoma In Situ (CIS) derived more pronounced benefits from the combination therapy. • Key Data: In the CIS subgroup, the HR for EFS decreased to 0.63, indicating a stronger clinical benefit signal compared to the overall population. This finding provides a reference for precision treatment stratification in high-risk NMIBC.
05 Safety Analysis: Significant Increase in Grade 3/4 Adverse Events
While the efficacy data are encouraging, the toxicity burden associated with systemic immunotherapy cannot be overlooked. Safety comparisons showed: • Toxicity Rates: The incidence of Grade 3 or 4 Adverse Events (AEs) rose to 24.5% in the BCG plus ICI group, compared to only 6.1% in the BCG monotherapy group. • Toxicity Profile: No new or unexpected safety signals were observed; the increased risk was primarily driven by known immune-related Adverse Events (irAEs).
06 Conclusion and Outlook: Awaiting Validated Biomarkers for Clinical Translation
Prof. Saad M.A. concluded that while the combination of BCG and systemic ICIs during both induction and maintenance phases significantly improves EFS in high-risk NMIBC, it is not yet a “practice-changing protocol.” This is due to the significantly increased toxicity burden and the lack of mature Overall Survival (OS) data. Future Directions: The next critical step is to identify and validate biomarkers to better stratify patients. This will allow clinicians to identify those most likely to derive a survival benefit from intensified regimens while maintaining manageable toxicity.
