A novel study evaluating the addition of venetoclax to the intensive chemotherapy regimen of cladribine, idarubicin, and cytarabine as a front-line therapy demonstrated high rates of disease control and remissions in younger patients with newly diagnosed acute myeloid leukemia (AML) and high-risk myelodysplastic syndrome (MDS), according to new findings presented by Reville et al at the 64th American Society of Hematology (ASH) Annual Meeting and Exposition (Abstract 709). In the phase II study, 96% of patients responded to treatment and 90% had no measurable disease detected in a bone marrow sample.
“Venetoclax has been a breakthrough for [patients with AML who] are ineligible for intensive therapy. This data continues to demonstrate the benefit of including venetoclax with the [cladribine, idarubicin, and cytarabine] induction regimen,” highlighted lead study author Patrick K. Reville, MD, MPH, a hematology and oncology fellow in the Department of Leukemia at The University of Texas MD Anderson Cancer Center. “This regimen is leading to unprecedented response and measurable residual disease–negativity rates. As we continue to follow participants, we are encouraged by their long-term outcomes and survival.”
The single-center, single-arm trial enrolled 67 patients aged 48 years on average. Among the cohort, 60 patients had AML, four patients had high-risk MDS, and three patients had a mixed-phenotype acute leukemia.
The composite complete response rate was 96% across all patients and 100% for patients with both MDS and mixed-phenotype acute leukemia with a myeloid-predominant clone. Most patients went on to receive a subsequent allogeneic stem cell transplant—including 70% of those who responded to treatment.
Encouragingly, with a median follow-up of just over 2 years—the average duration of response—event-free survival and overall survival have not yet been reached. At 12 months, the estimated event-free survival rate was 70%, the estimated overall survival rate was 86%, and 74% of responding patients were estimated to have an ongoing response.
The most common nonhematologic adverse event that participants experienced was febrile neutropenia, which was managed. Researchers expect to continue following the patients in this study to evaluate whether this regimen may be a safe and effective induction treatment strategy for this patient population.
Disclosure: The research in this study was funded by the Joe Moakley Leukemia SPORE and MD Anderson institutional support. For full disclosures of the study authors, visit ash.confex.com.
