Trial results for a Phase 3 study (NCT04637594) investigating atezolizumab and other immune checkpoint inhibitors in locally advanced urothelial carcinoma were posted on ClinicalTrials.gov on 2026-03-20. The posted data, however, indicates 0% for all reported survival and progression-free survival rates, and 0 participants experiencing Grade 3 or greater adverse events, suggesting the data may be preliminary or incomplete.
Background
The trial aimed to evaluate the optimal duration of immune checkpoint inhibitor treatment for patients with locally advanced urothelial carcinoma. Atezolizumab is an immunotherapy that, along with other monoclonal antibodies such as avelumab, durvalumab, pembrolizumab, and nivolumab, may help the body's immune system attack cancer cells and interfere with their ability to grow and spread.
Trial design
The study (NCT04637594) is a Phase 3 trial with an enrollment of 3 participants. It investigates the optimal length of treatment with immune checkpoint inhibitors, including atezolizumab, for patients with locally advanced urothelial carcinoma, encompassing bladder, renal pelvis, ureter, and urethral urothelial carcinoma. The trial compares survival outcomes between patients who discontinue immune checkpoint inhibitor treatment after approximately one year and those who continue treatment.
Key results
The posted results for the trial show the following measurements for both Arm A and Arm B:
- Overall Survival (OS) Rate at 12 Months: 0 percentage of participants
- Progression-free Survival (PFS) Rate at 12 Months: 0 percentage of participants
- Immune-related Progression-free Survival (iPFS) Rate at 12 Months: 0 percentage of participants
- Number of Patients Experiencing Grade 3 or Greater Adverse Events (AEs): 0 Participants
These uniform zero values across all reported outcomes for both arms suggest that the data posted may represent preliminary placeholders or an early stage of data collection, rather than final or interim efficacy and safety results.
What this means
Based on the currently posted data, which shows 0% for all survival and progression-free survival rates and 0 adverse events, no conclusions can be drawn regarding the efficacy or safety profile of different immune checkpoint inhibitor treatment durations in locally advanced urothelial carcinoma. The low enrollment of 3 participants further suggests that these results are not indicative of the full trial outcomes. Clinicians and researchers will need to await more complete data from this Phase 3 study to understand the implications for treatment protocols.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT04637594, titled "Trying to Find the Correct Length of Treatment With Immune Checkpoint Therapy," were posted on 2026-03-20 on clinicaltrials.gov.