NCT07244705

A Study of ABT-301 Plus Tislelizumab With Bevacizumab in pMMR/Non-MSI-H Locally Advanced or mCRC

An Open-label, Multicenter, Phase 1/2 Study Exploring the Safety and Efficacy of ABT-301 in Combination With Tislelizumab and Bevacizumab in Participants With Proficient Mismatch Repair (pMMR)/Non-Microsatellite Instability-High (Non-MSI-H) Locally Advanced or Metastatic Colorectal Cancer (mCRC)

• Status: Recruiting
• Phase: Phase 1 / Phase 2
• Study type: Interventional
• Enrollment: 66 (estimated)
• Sponsor: Anbogen Therapeutics, Inc. · Industry
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

The goal of this clinical trial is to evaluate the safety and tolerability of escalating doses of ABT-301 in combination with fixed doses of tislelizumab 200 mg IV infusion and bevacizumab 7.5 mg/kg IV infusion Q3W, in participants with pMMR/non-MSI-H colorectal cancer (CRC). It will also determine the maximum tolerated dose (MTD) and select the recommended Phase 2 dose (RP2D) of ABT-301. Participants will receive ABT-301 administered once daily (QD ±3 hours) or twice daily (Q12H ±3 hours, at least 9 hours apart) with water in 21-day treatment cycles. Tislelizumab 200 mg IV and bevacizumab 7.5 mg/kg IV Q3W will be given in both parts of the study.

Conditions

• Colorectal Cancer (Diagnosis)
• Colorectal Cancer Metastatic
• Colorectal Cancer (CRC)
• Immunotherapy

Interventions

Type	Name	Description
DRUG	ABT-301	ABT-301 is an oral histone deacetylase inhibitor (HDACi) administered in capsule form once daily (QD ±3 hours) or every 12 hours (Q12H ±3 hours, with at least 9 hours between doses) with water in 21-day treatment cycles. In Part 1 (dose-escalation phase), participants receive escalating doses of ABT-301 (50 mg QD, 100 mg QD, 50 mg Q12H, 150 mg QD, or 75 mg Q12H). Tislelizumab 200 mg and bevacizumab 7.5 mg/kg will be administered through IV infusion on Day 1 of every 21-day treatment cycle. This phase aims to determine the maximum tolerated dose (MTD) and/or recommended Phase 2 dose (RP2D) of ABT-301 when combined with tislelizumab and bevacizumab. In Part 2 (dose-optimization phase), two ABT-301 doses/schedules will be selected for further evaluation of antitumor activity, safety, and tolerability in adults with pMMR/non-MSI-H colorectal cancer (CRC).
DRUG	Tislelizumab	Tislelizumab is a humanized immunoglobulin G4-variant monoclonal antibody (mAb) blocking programmed cell death protein 1 (PD-1). Tislelizumab 200 mg will be administered through IV infusion on Day 1 of every 21-day treatment cycle in combination with ABT-301 and bevacizumab throughout both parts of the study.
DRUG	Bevacizumab (Avastin)	Bevacizumab (Avastin®) is a recombinant humanized monoclonal IgG1 antibody which binds to and neutralizes VEGF. Neutralization of VEGF by bevacizumab has been shown to inhibit the VEGF-induced proliferation of human endothelial cells in vitro and to decrease micro-vessel density and interstitial pressure in tumor xenografts in vivo. Bevacizumab 7.5 mg/kg will be administered through IV infusion on Day 1 of every 21-day treatment cycle in combination with ABT-301 and tislelizumab, throughout both parts of the study.

Timeline

• Start date: 2025-11-01
• Primary completion: 2028-04-01
• Completion: 2028-07-01
• First posted: 2025-11-24
• Last updated: 2025-11-24

Locations

15 sites across 2 countries: Australia, Taiwan

Regulatory

• FDA-regulated drug study