Fixed-Duration Combination Regimen Under Study in CLL
Posted: Thursday, September 17, 2020
The combination therapy regimen in obinutuzumab, ibrutinib, and venetoclax has been shown anticancer activity, with a potential cognitive benefit, in patients with treatment-naive and resistant chronic lymphocytic leukemia (CLL), according to a phase II trial published in the Journal of Clinical Oncology. “The combination regimen of obinutuzumab, ibrutinib, and venetoclax offers time-limited treatment that results in deep remissions and is now being studied in phase III cooperative group trials,” according to John C. Byrd, MD, of The Ohio State University, Columbus, and colleagues.
A total of 50 patients with CLL or small lymphocytic leukemia were enrolled in the study. Half of them were treatment-naïve, and half had relapsed or refractory disease. All patients were given obinutuzumab, ibrutinib, and venetoclax for a total of 14 cycles.
The researchers reported a mid-therapy overall response rate of 96% and a final overall response rate of 84% in treatment-naive patients. Patients with relapsed or refractory disease had a mid-therapy overall response rate of 92% and a final overall response rate of 88%. A total of 67% of treatment-naive patients and 50% of patients with resistant disease had undetectable minimal residual disease in the blood and marrow. At a median follow-up of 24.2 months and 21.5 months, the study had not reached median progression-free or overall survival. In terms of toxicity, neutropenia was found to be the most common adverse event, with 66% of patients experiencing grade III or IV events.
Of note, the investigators reported a “favorable impact” on both perceived and objective cognitive performance during treatment. “In contrast to chemotherapy, this regimen was not associated with diminished cognitive performance. Rather, patients exhibited maintenance, or even improvement, of cognitive performance,” the authors commented.
Disclosure: For full disclosures of the study authors, visit ascopubs.org.