Dasatinib - How It Works
Clinical pharmacology details from the US FDA-approved label: how Dasatinib works in your body, how it's absorbed, how long it stays active, and how it's eliminated.
Mechanism of Action
12.1 Mechanism of Action Dasatinib, at nanomolar concentrations, inhibits the following kinases: BCR-ABL, SRC family (SRC, LCK, YES, FYN), c-KIT, EPHA2, and PDGFRβ. Based on modeling studies, dasatinib is predicted to bind to multiple conformations of the ABL kinase. In vitro , dasatinib was active in leukemic cell lines representing variants of imatinib mesylate-sensitive and resistant disease. Dasatinib inhibited the growth of chronic myeloid leukemia (CML) and acute lymphoblastic leukemia (ALL) cell lines overexpressing BCR-ABL. Under the conditions of the assays, dasatinib could overcome imatinib resistance resulting from BCR-ABL kinase domain mutations, activation of alternate signaling pathways involving the SRC family kinases (LYN, HCK), and multi-drug resistance gene overexpression.
12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Dasatinib, at nanomolar concentrations, inhibits the following kinases: BCR-ABL, SRC family (SRC, LCK, YES, FYN), c-KIT, EPHA2, and PDGFRβ.
Based on modeling studies, dasatinib is predicted to bind to multiple conformations of the ABL kinase.
In vitro , dasatinib was active in leukemic cell lines representing variants of imatinib mesylate-sensitive and resistant disease.
Dasatinib inhibited the growth of chronic myeloid leukemia (CML) and acute lymphoblastic leukemia (ALL) cell lines overexpressing BCR-ABL.
Under the conditions of the assays, dasatinib could overcome imatinib resistance resulting from BCR-ABL kinase domain mutations, activation of alternate signaling pathways involving the SRC family kinases (LYN, HCK), and multi-drug resistance gene overexpression.
12.2 Pharmacodynamics Cardiac Electrophysiology Of 2,440 patients treated with dasatinib at all doses tested in clinical trials, 16 patients (<1%) had QTc prolongation reported as an adverse reaction.
Twenty-two patients (1%) experienced a QTcF > 500 ms.
In 865 patients with leukemia treated with dasatinib 70 mg BID in five Phase 2 studies, the maximum mean changes in QTcF (90% upper bound CI) from baseline ranged from 7 ms to 13.4 ms.
An analysis of the data from five Phase 2 studies in patients (70 mg BID) and a Phase 1 study in healthy subjects (100 mg single dose) suggests that there is a maximum increase of 3 to 6 milliseconds in Fridericia corrected QTc interval from baseline for subjects receiving therapeutic doses of dasatinib, with associated upper 95% confidence intervals <10 msec.
12.3 Pharmacokinetics The pharmacokinetics of dasatinib exhibits dose proportional increases in AUC and linear elimination characteristics over the dose range of 15 mg/day (0.15 times the lowest approved recommended dose) to 240 mg/day (1.7 times the highest approved recommended dose).
At 100 mg QD, the maximum concentration at steady state (C max ) is 82.2 ng/mL (CV% 69%), area under the plasma drug concentration time curve (AUC) is 397 ng/mL*hr (CV% 55%).
The clearance of dasatinib is found to be time-invariant.
When administered to adult healthy subjects as dispersed tablets in juice, the adjusted geometric mean ratio was 0.97 (90% CI: 0.85, 1.10) for C max and 0.84 (90% CI: 0.78, 0.91) for AUC as compared to intact tablets.
Absorption The maximum plasma concentrations (C max ) of dasatinib are observed between 0.5 hours and 6 hours (T max ) following oral administration.
Food Effect A high-fat meal increased the mean AUC of dasatinib following a single dose of 100 mg by 14%.
The total calorie content of the high-fat meal was 985 kcal.
The calories derived from fat, carbohydrates, and protein were 52%, 34%, and 14% for the high-fat meal.
Distribution The apparent volume of distribution is 2,505 L (CV% 93%).
Binding of dasatinib to human plasma proteins in vitro was approximately 96% and of its active metabolite was 93%, with no concentration dependence over the range of 100 ng/mL to 500 ng/mL.
Dasatinib is a P-gp substrate in vitro.
Pharmacokinetics
12.3 Pharmacokinetics The pharmacokinetics of dasatinib exhibits dose proportional increases in AUC and linear elimination characteristics over the dose range of 15 mg/day (0.15 times the lowest approved recommended dose) to 240 mg/day (1.7 times the highest approved recommended dose). At 100 mg QD, the maximum concentration at steady state (C max ) is 82.2 ng/mL (CV% 69%), area under the plasma drug concentration time curve (AUC) is 397 ng/mL*hr (CV% 55%). The clearance of dasatinib is found to be time-invariant. When administered to adult healthy subjects as dispersed tablets in juice, the adjusted geometric mean ratio was 0.97 (90% CI: 0.85, 1.10) for C max and 0.84 (90% CI: 0.78, 0.91) for AUC as compared to intact tablets. Absorption The maximum plasma concentrations (C max ) of dasatinib are observed between 0.5 hours and 6 hours (T max ) following oral administration. Food Effect A high-fat meal increased the mean AUC of dasatinib following a single dose of 100 mg by 14%. The total calorie content of the high-fat meal was 985 kcal. The calories derived from fat, carbohydrates, and protein were 52%, 34%, and 14% for the high-fat meal. Distribution The apparent volume of distribution is 2,505 L (CV% 93%). Binding of dasatinib to human plasma proteins in vitro was approximately 96% and of its active metabolite was 93%, with no concentration dependence over the range of 100 ng/mL to 500 ng/mL. Dasatinib is a P-gp substrate in vitro. Elimination The mean terminal half-life