Posted: Monday, July 10, 2023
William Joseph Chapin, MD, of Abramson Cancer Center at the University of Pennsylvania, Philadelphia, and colleagues presented the trial design for an ongoing phase II clinical trial at the 2023 American Society of Clinical Oncology (ASCO) Annual Meeting (Abstract TPS4184). The investigators will be evaluating the efficacy of vudalimab in patients with advanced biliary tract cancers who had previously received gemcitabine-based chemotherapy. Vudalimab is a novel bispecific antibody that targets PD-1 and CTLA-4. In this trial, 13 patients will be evaluated in the first stage and an additional 14 patients, in the second stage if responses were observed.
Combination immunotherapy approaches with PD-1 or PD-L1 inhibitors plus CTLA-4 inhibitors have shown improved overall response rates of 10.8% to 23% compared with single-agent PD-1 or PD-L1 inhibitors. As a bispecific antibody targeting both PD-1 and CTLA-4, vudalimab has demonstrated an overall response rate of 14.1% in a phase I dose-expansion cohort of patients with advanced malignancies, including those who had disease progression on prior immune checkpoint inhibitors.
In the ongoing phase II trial, vudalimab will be administered intravenously at a dose of 10 mg/kg on days 1 and 15 of a 28-day cycle. Inclusion criteria require patients with specific molecular variants to have received targeted therapy, unless contraindicated or refused. Patients who have received prior immune checkpoint inhibitor therapy are not eligible for the trial. Correlative studies will involve collecting peripheral blood samples to analyze circulating immune cells.
As of January 2023, eight patients have been enrolled in the trial, and enrollment is ongoing. The trial aims to determine the overall response rate of vudalimab in patients with advanced biliary tract cancers who have previously received gemcitabine-based chemotherapy.
Disclosure: Dr. Chapin reported no conflicts of interest. For full disclosures of the other study authors, visit coi.asco.org.