ASH 2020: Long-Term Update on Ibrutinib Plus Venetoclax in CLL
Posted: Friday, December 18, 2020
Patients with chronic lymphocytic leukemia (CLL) treated with ibrutinib and venetoclax had a sustained treatment response, and those who responded to treatment within the first 2 months of therapy had longer-term responses. Talha Munir, MBBS, of St. James University Hospital in Leeds, United Kingdom, presented these results on behalf of his colleagues at the 2020 American Society of Hematology (ASH) Annual Meeting and Exposition (Abstract 124).
This phase II trial enrolled 50 patients with relapsed or refractory CLL from May 2016 to November 2017. Patients were administered ibrutinib for 2 months, plus venetoclax. Patient bone marrow and peripheral blood samples were assessed at months 8, 14, and 26 to achieve minimal residual disease (MRD, < 0.0001 CLL cells) using flow cytometry. Patients who achieved MRD by month 8 stopped therapy at month 14, whereas those who achieved MRD at month 14 or 26 stopped therapy at month 26.
Within the trial cohort, 23 patients stopped therapy at or before 38 months, with 17 being due to achievement of MRD. The remaining 27 patients were still receiving at least one trial treatment at month 38, with an overall response rate of 81%. These responses continued to improve after 1 year of combination treatment, as 40% of patients achieved MRD at month 14, and 48% of patients achieved MRD at month 26.
After 4 months of therapy, the median log depletion in CLL cells was 2.9 for those achieving < 0.01% MRD at month 26, compared with 1.4 for patients with > 0.01% MRD at month 26. Among 20 evaluable patients with < 0.01% MRD at month 38, MRD depletion was achieved by 6 months in 35% of patients, 12 months in 70% of patients, and 24 months in 90% of patients.
The most common adverse effect was neutropenia (34 grade 3 or 4). There were 44 serious adverse events and 1,153 total adverse events (141 grade 3 or 4).
Disclosure: For a full list of authors’ disclosures, visit ash.confex.com.
