Evaluation of bleeding events in patients receiving acalabrutinib therapy.

Acalabrutinib is a next-generation, more selective, covalent Bruton tyrosine kinase inhibitor (BTKi), designed to have less toxicity, including bleeding, than the first-generation covalent BTKi ibrutinib. We performed a retrospective medical record review of 289 patients with B-cell malignancies treated with acalabrutinib to evaluate and describe bleeding events. Median acalabrutinib exposure was 40.8 months (range 0-81.6) with 83% of patients experiencing at least one bleeding event. Of these patients, 59%, 35%, and 6% had a clinically non-relevant minor, clinically relevant minor, or major bleed as their first, most severe event per ISTH criteria, respectively. For all bleed events, 24% were clinically relevant minor/major and 2.5% were CTCAE grade ≥3. Age >65, prior bleed history, and longer time on acalabrutinib therapy were found to be independent risk factors for clinically relevant minor/major bleeds. Additionally, 1263 procedures were identified, and the incidence of clinically non-relevant and clinically relevant minor/major bleeds related to procedures was 0.95% and 1.3%, respectively. In conclusion, with a long median exposure time, most bleeds were clinically non-relevant per ISTH criteria and CTCAE grade <3 for patients with B-cell malignancies treated with acalabrutinib.