ClinicalTrials.gov recorded primary completion on 22 July 2026 for a completed Phase 3 study of atezolizumab in participants with unresectable esophageal squamous cell carcinoma. The trial enrolled 760 participants and evaluated tiragolumab plus atezolizumab against atezolizumab with matching placebo and double placebo.

The supplied record does not include primary-outcome measurements, key analyses, or an adverse-event summary, so it does not provide comparative efficacy or safety results.

Background

The study evaluated atezolizumab, with or without tiragolumab, in participants with unresectable esophageal squamous cell carcinoma whose cancers had not progressed after definitive concurrent chemoradiotherapy. The record also included participants who were unable or unwilling to undergo surgery. Atezolizumab and tiragolumab were studied as trial interventions; the supplied data do not provide mechanism details or information about prior approvals.

Trial design

This Phase 3 trial, identified as NCT04543617, enrolled 760 participants with esophageal squamous cell carcinoma. Participants were randomized in a 1:1:1 ratio to three groups: tiragolumab plus atezolizumab, tiragolumab matching placebo plus atezolizumab, or double placebo. The study was listed as completed. No primary-outcome entries were supplied in the data.

What this means

The trial reached primary completion after evaluating three randomized treatment groups in a defined population with unresectable esophageal squamous cell carcinoma following definitive concurrent chemoradiotherapy. Because the supplied record contains no outcome measurements, analyses, confidence intervals, p-values, or adverse-event results, the event alone does not establish whether adding tiragolumab improved outcomes or changed safety compared with the other groups.

Source

Source: ClinicalTrials.gov, clinical trial registry record for “A Study of Atezolizumab With or Without Tiragolumab in Participants With Unresectable Esophageal Squamous Cell Carcinoma Whose Cancers Have Not Progressed Following Definitive Concurrent Chemoradiotherapy,” with primary completion recorded on 22 July 2026. Available at clinicaltrials.gov/study/NCT04543617.