Experience of using acalabrutinib therapy in patients with chronic lymphocytic leukemia/small lymphocytic lymphoma

Introduction. Thanks to scientific advances and discoveries in the study of tumor cell biology, new effective drugs for the treatment of chronic lymphocytic leukemia/ small lymphocytic lymphoma have emerged. Currently, there are drugs with different application points at the molecular level. One such drug is acalabrutinib, which is a selective second-generation inhibitors of Bruton tyrosine kinase and has a more favorable toxicity profile.Objective. To evaluate the efficacy of acalabrutinib in patients with chronic lymphocytic leukemia/small lymphocytic lymphoma.Materials and methods. Since February 2020 acalabrutinib (100 mg 2 p/day orally) has been administered to 7 patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (mean age 64 years) at the Hematology Research Center. Six patients received acalabrutinib in 1st-line therapy and one patient received acalabrutinib in 2nd-line therapy. The mean comorbidity index (CIRS) of the patients was 10 points (range, 8 to 14). Most patients had at least one of the adverse prognostic factors - IGHV nonmutated gene status, TP53 gene aberration (del17p13 and/or TP53 gene mutation), complex karyotype disorders.Results. All patients achieved partial remission of the disease (overall response 100% in the form of regression of B-symptoms, lymphocytic leukocytosis, splenomegaly) at the control period of treatment with acalabrutinib +12 months. The most frequent adverse events when taking acalabrutinib were the occurrence of headache in the first month of taking the drug, spontaneous subcutaneous hematomas. No hematologic toxicity, infectious complications, or cardiac complications were noted. At a median follow-up of 34 months, no patient showed disease progression.Conclusions. The selective Bruton tyrosine kinase inhibitor acalabrutinib has demonstrated high efficacy in patients with adverse risk factors, good tolerability and minimal toxicity, including in comorbid patients.