Hidekazu Itamura1, Yasushi Kubota2, Takero Shindo1, Toshihiko Ando1, Kensuke Kojima1, Shinya Kimura1. 1. Division of Hematology, Respiratory Medicine and Oncology, Department of Internal Medicine, Faculty of Medicine, Saga University, Saga, Japan. 2. Division of Hematology, Respiratory Medicine and Oncology, Department of Internal Medicine, Faculty of Medicine, Saga University, Saga, Japan. Electronic address: kubotay@cc.saga-u.ac.jp.
Abstract
BACKGROUND: The clinical outcomes of patients with chronic myeloid leukemia (CML) treated with BCR-ABL tyrosine kinase inhibitors has improved markedly; however, the occurrence of adverse events (AEs) means that elderly patients often cannot be administered the standard dose. Nevertheless, some patients treated with low doses of tyrosine kinase inhibitor have achieved good molecular responses. PATIENTS AND METHODS: We retrospectively analyzed the efficacy and safety of low-dose dasatinib treatment of elderly CML patients. The study enrolled 21 patients with newly diagnosed, imatinib-resistant, or imatinib-intolerant chronic phase CML. All the patients were aged ≥ 65 years and received dasatinib at a dose of < 100 mg/day. Of these 21 patients, 77% had newly diagnosed CML. RESULTS: Overall, 91% and 72% of patients received a mean dasatinib dose of ≤ 50 mg and ≤ 20 mg, respectively. A molecular response of MR3 (major molecular response, indicating > 3 log reduction in the number of leukemic cells), MR4, and MR4.5 were achieved in 96%, 77%, and 62% of the patients, respectively. Of the 15 patients who received a mean dose of ≤ 20 mg, 94% achieved a major molecular response, and 74% achieved MR4. The most common nonhematologic AE was plural effusion (29%), which was controlled by diuretics and regulating the drug dose. CONCLUSION: Low-dose (eg, ≤ 20 mg) dasatinib therapy generates an adequate molecular response in most elderly patients with chronic phase CML without causing severe AEs.
BACKGROUND: The clinical outcomes of patients with chronic myeloid leukemia (CML) treated with BCR-ABL tyrosine kinase inhibitors has improved markedly; however, the occurrence of adverse events (AEs) means that elderly patients often cannot be administered the standard dose. Nevertheless, some patients treated with low doses of tyrosine kinase inhibitor have achieved good molecular responses. PATIENTS AND METHODS: We retrospectively analyzed the efficacy and safety of low-dose dasatinib treatment of elderly CMLpatients. The study enrolled 21 patients with newly diagnosed, imatinib-resistant, or imatinib-intolerant chronic phase CML. All the patients were aged ≥ 65 years and received dasatinib at a dose of < 100 mg/day. Of these 21 patients, 77% had newly diagnosed CML. RESULTS: Overall, 91% and 72% of patients received a mean dasatinib dose of ≤ 50 mg and ≤ 20 mg, respectively. A molecular response of MR3 (major molecular response, indicating > 3 log reduction in the number of leukemic cells), MR4, and MR4.5 were achieved in 96%, 77%, and 62% of the patients, respectively. Of the 15 patients who received a mean dose of ≤ 20 mg, 94% achieved a major molecular response, and 74% achieved MR4. The most common nonhematologic AE was plural effusion (29%), which was controlled by diuretics and regulating the drug dose. CONCLUSION: Low-dose (eg, ≤ 20 mg) dasatinib therapy generates an adequate molecular response in most elderly patients with chronic phase CML without causing severe AEs.