er transporters.
Metabolism
Bosutinib is primarily metabolized by CYP3A4. The major circulating metabolites identified in plasma are oxydechlorinated (M2) bosutinib (19% of parent exposure) and N-desmethylated (M5) bosutinib (25% of parent exposure), with bosutinib N-oxide (M6) as a minor circulating metabolite. All the metabolites were deemed inactive.
Elimination
In patients with CML given single-oral doses of Bosulif (500mg) with food, the mean terminal phase elimination half-life (t1/2) was 22.5 (1.7) hours, and the mean (SD) clearance (Cl/F) was 189 (48) L/h. In six healthy male subjects given a single oral dose of [14C] radiolabeled bosutinib, 91.3% of the dose was recovered in feces and 3% of the dose recovered in urine.
Hepatic Impairment
In a dedicated hepatic impairment trial, a single dose of Bosulif 200 mg was administered with food to 18 hepatically impaired volunteers (Child-Pugh classes A, B, and C) and 9 matched healthy volunteers. Cmax of bosutinib increased 2.4-fold, 2-fold, and 1.5-fold, respectively, in Child-Pugh classes A, B, and C, and bosutinib AUC increased 2.3-fold, 2-fold, and 1.9-fold, respectively.
Drug Interactions
CYP3A Inhibitors
In a cross-over trial of 24 healthy volunteers, a single dose of 100 mg of Bosulif was either administered alone or in combination with five daily doses of 400 mg of ketoconazole under fasting conditions. Ketoconazole increased bosutinib Cmax and AUC 5.2-fold and 8.6-fold, respectively.
CYP3A Inducers
In a cross-over trial of 24 healthy volunteers, a single dose of 500 mg of Bosulif was either administered alone or in combination with six daily doses of 600 mg of rifampin under fed conditions. Rifampin decreased bosutinib Cmax and AUC by 86% and 94%, respectively.
P-gp Substrates
An in vitro study suggests that Bosulif has the potential to increase the plasma concentrations of drugs that are P-gp substrates. The estimated I/IC50 was 0.19, when considering the Cmax at the 500 mg dose of Bosulif.
pH Altering Medications
Bosulif displays pH-dependent aqueous solubility, in vitro. In a cross-over trial in 24 healthy volunteers, a single oral dose of 400 mg of Bosulif was either administered alone or in combination with multiple-oral doses of 60 mg of lansoprazole under fasting conditions. Lansoprazole decreased bosutinib Cmax and AUC by 46% and 26%, respectively.
QT/QTc Prolongation
The effect of a single dose of bosutinib 500 mg alone and with ketoconazole on the QTc interval was eva luated in a randomized, placebo- and active-controlled (moxifloxacin 400 mg) two or three-period crossover thorough QT study in 70 healthy subjects. No significant changes in placebo adjusted, baseline-corrected QTc were observed.
Nonclinical Toxicology
Carcinogenesis, Mutagenesis, Impairment of Fertility
A 2-year carcinogenicity study was conducted orally in rats at bosutinib doses up to 25 mg/kg/day in males and 15 mg/kg/day in females. The exposures achieved at the high dose were approximately 1.5- to 3-fold the human exposure (based on AUC) at the bosutinib dose of 500 mg/day. The study was negative for carcinogenic findings.
Bosutinib was not mutagenic or clastogenic in a battery of tests, including the bacteria reverse mutation assay (Ames Test), the in vitro assay using human peripheral blood lymphocytes and the micronucleus test in orally treated male mice.
In a rat fertility study, drug-treated males were mated with untreated females, or untreated males were mated with drug-treated fe |
