- Acalabrutinib, a novel Bruton tyrosine kinase inhibitor, demonstrated high-level tolerability and response in patients with chronic lymphocytic leukemia (CLL) who were intolerant to ibrutinib.
Why this matters
- Ibrutinib has demonstrated excellent efficacy in this setting; however, 9%-23% of patients experience treatment-limiting adverse effects.
- Study to investigate acalabrutinib monotherapy in 33 ibrutinib-intolerant patients with CLL.
- 64 (range, 50-82) years median patient age.
- Many patients had high-risk disease.
- Patients had received a median of 4 (range, 2-13) prior therapies.
- Funding: National Cancer Institute, National Institutes of Health, Acerta Pharma.
- 75.8% (95% CI, 57.7%-88.9%) overall response rate (ORR; defined as partial response with lymphocytosis or better [≥PRL]).
- 3.0% complete remission.
- All patients achieved at least stable disease.
- 1.9 (range, 1.6-19.2) months median time to ≥PRL.
- Median duration of response (DOR) was not reached.
- 82% (95% CI, 59%-93%) had DOR of ≥12 months.
- 70% of patients remained on acalabrutinib at a median of 19.0 (range, 0.7-30.6) months.
- No patients required acalabrutinib dose reductions.
- Grade ≥3 adverse events (AEs) occurring in >3% of patients included neutropenia (12%) and thrombocytopenia (9%).
- Only 3 patients discontinued acalabrutinib due to AEs.
- Limited sample size.