Posted: Monday, January 31, 2022
Many patients treated with the combination regimen of ibrutinib plus fludarabine, cyclophosphamide, and rituximab (FCR) for chronic lymphocytic leukemia (CLL) maintained deep responses after long-term follow-up. This study, conducted by Jennifer R. Brown, MD, PhD, of the Dana-Farber Cancer Institute, Boston, and colleagues, was presented at the 2021 American Society of Hematology (ASH) Annual Meeting & Exposition (Abstract 640).
“[Ibrutinib, fludarabine, cyclophosphamide, and rituximab] is worthy of exploring in comparative studies in younger, fit CLL patients who desire the possibility of functional cure with time-limited therapy,” concluded the authors.
This multicenter, phase II trial enrolled 85 patients (median age, 55) who had CLL. Patients were treated with 420 mg of ibrutinib daily for 7 days, followed by ibrutinib in combination with FCR for up to 6 cycles. Patients who responded to therapy continued with ibrutinib maintenance therapy, and therapy was discontinued after 2 years for patients who achieved bone marrow undetectable measurable residual disease (MRD).
After a median of 40.3 months of follow-up, the rate of complete response with bone marrow undetectable MRD at any point of the study was 55%, and the best rate of bone marrow undetectable MRD was 84%. After 2 years of ibrutinib maintenance treatment, the rate of complete response/complete response with incomplete hematologic recovery was 77%, the rate of bone marrow undetectable MRD was 81%, and the rate of peripheral blood undetectable MRD was 81%. Overall survival for all patients was 99%, and progression-free survival was 97%.
The most common grade 3 or 4 adverse events were hematologic, with 40% experiencing neutropenia, 32% experiencing thrombocytopenia, and 11% experiencing anemia. Two patients developed myelodysplastic syndrome; however, there were no cases of Richter's transformation. One patient died after 17 months of ibrutinib maintenance treatment due to sudden cardiac death.
Disclosure: For a full list of author disclosures, visit ash.confex.com.