results in activation of estrogenic pathways in some tissues (agonism) and blockade of estrogenic pathways in others (antagonism).
12.3 Pharmacokinetics
Absorption
Following a single oral administration of OSPHENA 60 mg tablet in postmenopausal women under fasted condition, peak median serum concentrations was reached at approximately 2 hours (range: 1 to 8 hours) post-dose (see Figure 2). Mean ospemifene Cmax and AUC0-inf were 533 ng/mL and 4165 ng•hr/mL, respectively. After a single oral administration of OSPHENA 60 mg tablet in postmenopausal women with a high fat/high calorie (860 kcal) meal, Cmax was reached at approximately 2.5 hours (range: 1 to 6 hours) post-dose. Mean ospemifene Cmax and AUC0-inf were 1198 ng/mL and 7521 ng•hr/mL, respectively. The absolute bioavailability of ospemifene was not eva luated. Ospemifene exhibits less than dose-proportional pharmacokinetics from 25 to 200 mg with ospemifene capsule formulation. Accumulation of ospemifene with respect to AUC0-inf was approximately 2 after twelve weeks of daily administration. Steady-state was reached after nine days of ospemifene administration.
Figure 2: Mean serum concentration profile of ospemifene following a single oral administration of OSPHENA 60 mg tablet in postmenopausal women under fed (N=28) and fasted (N=91) conditions
Food Effect
In general, food increased the bioavailability of ospemifene by approximately 2-3 fold. In a cross-study comparison, single dose OSPHENA 60 mg tablet administered with a high fat/high calorie meal (860 kcal) in postmenopausal women increased Cmax and AUC0-inf by 2.3- and 1.7-fold, respectively, compared to fasted condition. Elimination half-life and time to maximum concentration (Tmax) were unchanged in the presence of food. In two food effect studies in healthy males using different ospemifene tablet formulations Cmax and AUC0-inf increased by 2.3- and 1.8-fold, respectively, with a low fat/low calorie meal (300 kcal) and increased by 3.6- and 2.7-fold, respectively, with a high fat/high calorie meal (860 kcal), compared to fasted condition. OSPHENA should be taken with food [see Dosage and Administration (2.1)].
Distribution
OSPHENA is highly (>99 percent) bound to serum proteins. The apparent volume of distribution is 448 L.
Metabolism
In vitro experiments with human liver microsomes indicated that ospemifene primarily undergoes metabolism via CYP3A4, CYP2C9 and CYP2C19. The major metabolite was 4-hydroxyospemifene. The apparent total body clearance is 9.16 L/hr using a population approach.
Excretion
The apparent terminal half-life of ospemifene in postmenopausal women is approximately 26 hours. Following an oral administration of ospemifene, approximately 75% and 7% of the dose was excreted in feces and urine, respectively. Less than 0.2% of the ospemifene dose was excreted unchanged in urine.
Use in Specific Populations
Pediatric
The pharmacokinetics of ospemifene in pediatric patients has not been eva luated [see Use in Specific Populations (8.4)].
Geriatric
No differences in ospemifene pharmacokinetics were detected with regard to age (range 40 to 80 years) [see Use in Specific Populations (8.5)].
Race
Race did not have clinically relevant effect on ospemifene pharmacokinetics.
Renal Impairment
In women with severe renal impairment (CrCL <30 mL/min), the Cmax and AUC0-inf for ospemifene following