A Phase Two, Single-Arm, Open-Label Study With Dostarlimab Monotherapy in Participants With Untreated Stage II/III...

Area of Science:

• Oncology
• Immunotherapy
• Gastrointestinal Cancers

Background:

• Colorectal cancer (CRC) is a leading cause of cancer mortality globally, with rectal cancer (RC) comprising a significant subset.
• Mismatch repair deficient (dMMR) locally advanced RC presents a unique treatment challenge.
• Emerging data suggests immune-checkpoint inhibitors like dostarlimab may offer a novel therapeutic approach.

Purpose of the Study:

• To evaluate the efficacy and safety of dostarlimab monotherapy in patients with previously untreated locally advanced dMMR rectal cancer.
• To assess the clinical complete response (cCR) rate and long-term outcomes.
• To provide international multicentric data on immunotherapy response in dMMR/MSI-H RC.

Main Methods:

• AZUR-1 is a phase 2, multicenter, open-label, single-arm study (NCT05723562).
• Approximately 150 patients with dMMR or MSI-H locally advanced RC will receive dostarlimab 500 mg IV every 3 weeks for 9 cycles.
• Primary endpoint is cCR by independent central review at 12 months; secondary endpoints include long-term survival and organ preservation.

Main Results:

• This section is not yet available as the study is ongoing.

Conclusions:

• The AZUR-1 study will assess the efficacy of dostarlimab in dMMR/MSI-H RC.
• Novel aspects include long follow-up and standardized response assessment.
• The study aims to provide robust international data on immunotherapy outcomes in this patient population.