Ibrutinib Plus Venetoclax in CLL: Oral Nonchemotherapy Regimen Under Study
Posted: Wednesday, August 4, 2021
The Bruton’s tyrosine kinase inhibitor ibrutinib plus the BCL2 inhibitor venetoclax may prove to be useful as first-line treatment in patients with chronic lymphocytic leukemia (CLL), and the treatment responses appeared to be durable for several years. Nitin Jain, MD, of The University of Texas MD Anderson Cancer Center, Houston, and colleagues published the results of this nonrandomized phase II trial in JAMA Oncology.
“These long-term results show that 2 years of oral targeted therapy can achieve lasting disease remission for patients with CLL,” said Dr. Jain in an institutional press release. “I think this will be one of several standard-of-care treatments available for patients with CLL.”
This study enrolled 80 patients with treatment-naive CLL from August 2016 through June 2018. Patients enrolled had at least one of the following features: del(17p), TP53-mutated CLL, del(11q), unmutated IGHV, or age > 65. Nearly all patients (92%) had one of the aforementioned high-risk genetic anomalies. Patients received 420 mg of ibrutinib daily as monotherapy for 3 cycles; then venetoclax was added with a ramp-up dose to 400 mg per day for 24 cycles of combination therapy.
After over 3 years of follow-up (38.5 months), 75% of patients achieved bone marrow undetectable measurable residual disease (MRD) remission as their best response. Specifically, 56% of patients had achieved bone marrow undetectable MRD at 12 cycles, and 66% of patients had no measurable bone marrow disease at 24 cycles. These strong responses were seen regardless of TP53 mutation or IGHV mutation. The progression-free survival at 3 years was 93%, and the overall survival was 96%. No patients enrolled had CLL progression, whereas two patients underwent Richter’s transformation.
The most common grade 3 or higher hematologic adverse event was neutropenia, seen in 51% of patients. In addition, 2% of patients had grade 3 thrombocytopenia. Commonly seen grade 3 or higher nonhematologic adverse events included hypertension (10%), atrial fibrillation/flutter (10%), and arthralgia (2%).
Disclosure: For a full list of authors’ disclosures, visit jamanetwork.com.
