Study of Atezolizumab and Bevacizumab in Adults With Gastrointestinal Cancers Showing Positive ctDNA After Curative Treatment

What this Trial Is About

Researchers are evaluating new treatments for gastrointestinal GI cancers in patients who have completed all standard curative therapies but still show microscopic residual disease. This is a non-randomized, open-label, multi-cohort pilot trial enrolling 20 patients with colorectal, gastric, pancreatic, hepatocellular, intra- or extra-hepatic biliary tract, and gallbladder adenocarcinomas confirmed by tissue testing. The goal is to study patients who have positive SignateraTM tumor-informed ctDNA tests despite no visible disease on imaging, to explore the effects of the investigational combination therapy in this setting. Participants will receive intravenous infusions of atezolizumab 1200 mg and bevacizumab 15 mgkg on Day 1 of each 21-day cycle, repeated every three weeks for up to 12 months or until disease recurrence, ctDNA progression, unacceptable side effects, or withdrawal. This combination is designed to target cancer pathways and blood vessel growth. Treatments will continue under medical supervision with study drugs provided to participants. No placebo groups are used in this study. Throughout the study, patients will be closely monitored with physical exams, imaging scans, and blood tests including ctDNA assessments to measure cancer markers and treatment responses at specified intervals. Safety will be assessed by tracking side effects using established criteria. Researchers will also record enrollment rates and reasons for any enrollment failures. Participants will be followed for up to one year, with ongoing evaluations to assess treatment impact and disease progression.

Evaluating Novel Therapies in ctDNA Positive GI Cancers