The combination of atezolizumab and BCG in high-risk non-muscle invasive bladder cancer: results of the phase Ib/II BladderGATE clinical trial.

BACKGROUND

BladderGATE evaluated the safety, tolerability, and efficacy of intravenous (IV) atezolizumab combined with intravesical Bacillus Calmette-Guérin (BCG) in patients with BCG-naïve high-risk non-muscle invasive bladder cancer (NMIBC).

MATERIALS AND

METHODS

This was a phase Ib/II open-label, nonrandomized, dose de-escalation clinical trial of atezolizumab (1200 mg IV infusion on day 1 of each 21-day cycle) plus BCG (1 instillation/week) with an induction treatment period of 6 weeks, followed by a maintenance treatment period of 52 weeks maximum. During induction, dose-limiting toxicity (DLT) and maximum tolerated dose of atezolizumab were determined. The primary study outcome was recurrence-free survival (RFS).

RESULTS

A total of 36 patients with high-risk NMIBC with a median age of 70 years were enrolled in this study. Twenty participants completed the whole treatment schedule. No DLTs were recorded during the study period. The median RFS was not reached; RFS rates were 83% (95% CI 70.6%-95.4%) and 73% (95% CI 57.4%-88.2%) at the end of the first and second year, respectively. The incidence of serious drug-related adverse events was low. Additionally, no impairment in Health-related quality of life status throughout the study was observed.

CONCLUSIONS

IV atezolizumab plus intravesical BCG in high-risk BCG-naïve NMIBC patients resulted in a high RFS rate and a manageable safety profile. These results appear consistent with those of the ALBAN study, which did not demonstrate a significant benefit of this combination over BCG alone.