A promising oral drug for chronic lymphocytic leukemia (CLL) has produced durable remissions for patients in clinical trials without triggering a debilitating side effect that’s common with existing treatments.
“PCI-32765, one of a new class of experimental drugs called B-cell receptor inhibitors, has shown impressive potential in these clinical trials for its effectiveness and particularly for its relatively minimal toxicity,” says lead investigator Susan O’Brien, M.D., professor in MD Anderson’s Department of Leukemia.
Of 27 CLL patients treated at a dose of 420 milligrams daily, 70% had complete or partial remission at 10.2 months of median follow-up. Six-month, progression-free survival was 92%. Similar results were seen among 34 patients treated at an 840 mg dose.
CLL is treated with combination chemotherapies that can cause myelosuppression — inhibited bone marrow function leading to decreased production of blood cells. The resulting susceptibility to infection can be a serious problem for patients, O’Brien says. “PCI-32765 is not myelosuppressive.”
Reported in December 2011 at the 53rd Annual Meeting of the American Society of Hematology.