inistration initially authorised), there was no clinically meaningful difference in the systemic steady-state exposure of ceritinib for the 450 mg with food arm (N=36) compared to the 750 mg fasted arm (N=31), with only small increases in steady-state AUC (90% CI) by 4% (-13%, 24%) and Cmax (90% CI) by 3% (-14%, 22%). In contrast, the steady-state AUC (90% CI) and Cmax (90% CI) for the 600 mg with food arm (N=30) increased by 24% (3%, 49%) and 25% (4%, 49%), respectively, compared to the 750 mg fasted arm. The maximum recommended dose of Zykadia is 450 mg taken orally once daily with food (see section 4.2).
After single oral administration of ceritinib in patients, plasma exposure to ceritinib, as represented by Cmax and AUClast, increased dose-proportionally over the 50 to 750 mg dose range under fasted conditions. In contrast with single-dose data, pre-dose concentration (Cmin) after repeated daily dosing appeared to increase in a greater than dose-proportional manner.
Distribution
Binding of ceritinib to human plasma proteins in vitro is approximately 97% in a concentration independent manner, from 50 ng/ml to 10,000 ng/ml. Ceritinib also has a slight preferential distribution to red blood cells, relative to plasma, with a mean in vitro blood-to-plasma ratio of 1.35. In vitro studies suggest that ceritinib is a substrate for P-glycoprotein (P-gp), but not of breast cancer resistance protein (BCRP) or multi-resistance protein 2 (MRP2). The in vitro apparent passive permeability of ceritinib was determined to be low.
In rats, ceritinib crosses the intact blood brain barrier with a brain-to-blood exposure (AUCinf) ratio of about 15%. There are no data related to brain-to-blood exposure ratio in humans.
Biotransformation
In vitro studies demonstrated that CYP3A was the major enzyme involved in the metabolic clearance of ceritinib.
Following a single oral administration of radioactive ceritinib dose at 750 mg fasted, ceritinib was the main circulating component in human plasma. A total of 11 metabolites were found circulating in plasma at low levels with mean contribution to the radioactivity AUC of ≤2.3% for each metabolite. Main biotransformation pathways identified in healthy subjects included mono-oxygenation, O-dealkylation, and N-formylation. Secondary biotransformation pathways involving the primary biotransformation products included glucuronidation and dehydrogenation. Addition of a thiol group to O-dealkylated ceritinib was also observed.
Elimination
Following single oral doses of ceritinib under fasted conditions, the geometric mean apparent plasma terminal half-life (T½) of ceritinib ranged from 31 to 41 hours in patients over the 400 to 750 mg dose range. Daily oral dosing of ceritinib results in achievement of steady-state by approximately 15 days and remains stable afterwards, with a geometric mean accumulation ratio of 6.2 after 3 weeks of daily dosing. The geometric mean apparent clearance (CL/F) of ceritinib was lower at steady-state (33.2 litres/hour) after 750 mg daily oral dosing than after a single 750 mg oral dose (88.5 litres/hour), suggesting that ceritinib demonstrates non-linear pharmacokinetics over time.
The primary route of excretion of ceritinib and its metabolites is in the faeces. Recovery of unchanged ceritinib in the faeces accounts for a mean 68% of an oral dose. Only 1.3% of the administered oral dose is recovered in the urine.
Special populations
Hepatic impairment
The effect of h |
