Phase III Randomized Trial of Concurrent Chemoradiotherapy With or Without Atezolizumab in Localized Muscle Invasive Bladder Cancer

National Cancer Institute/SWOG/Alliance/ECOG-ACRIN
Study Design: 
This is a randomized trial for patients with localized muscle-invasive bladder cancer who have refused or are unfit for radical cystectomy whereby patients are randomized to radiation therapy (three-dimensional conformal or intensity-modulated) with chemotherapy as per the treating physician with or without atezolizumab. The chemotherapy can consist of either gemcitabine, cisplatin, or fluorouracil and mitomycin. Patients treated in the atezolizumab arm are treated every 3 weeks for up to 6 months.
Chemoradiation has an established therapeutic role in localized muscle-invasive bladder cancer. This trial is designed to understand the potential of immunotherapy, specifically atezolizumab, to enhance the bladder intact even-free survival rate with chemoradiation.
The primary outcome is bladder intact event-free survival (BI-EFS) rate for up to 5 years. This composite endpoint includes the absence of muscle invasive bladder recurrence, regional pelvic soft tissue or nodal recurrence, distant metastases, bladder cancer or toxicity related death or cystectomy). Secondary endpoints include: overall survival at 5 years, disease-specific survival, NMIBC recurrence rate, cystectomy rate, and several immunologic and biologic endpoints.
This trial is ambitious and the criteria for tradiational chemoradiation or trimodal therapy has been expanded in this trial to allow patients with unilateral hydronephrosis and non-diffuse CIS to be enrolled. These clinical features are typically associated with poor response to bladder-sparing therapy so it will be interesting to see how the addition of atezolizumab impacts patients with these features on the trial. The correlatives are extensive and may provide clues towards prediction of responses.
This trial is actively accruing patients and has accrued 119 of the 475 planned enrollment.