8.1Pregnancy
VYTORIN Risk Summary Discontinue VYTORIN when pregnancy is recognized. Alternatively, consider the ongoing therapeutic needs of the individual patient. VYTORIN decreases synthesis of cholesterol and possibly other biologically active substances derived from cholesterol; therefore, VYTORIN may cause fetal harm when administered to pregnant patients based on the mechanism of action [see Clinical Pharmacology (12.1) ] .
In addition, treatment of hyperlipidemia is not generally necessary during pregnancy. Atherosclerosis is a chronic process and the discontinuation of lipid-lowering drugs during pregnancy should have little impact on the outcome of long-term therapy of primary hyperlipidemia for most patients. Available data from case series and prospective and retrospective observational cohort studies over decades of use with statins in pregnant women have not identified a drug-associated risk of major congenital malformations.
Published data from prospective and retrospective observational cohort studies with VYTORIN use in pregnant women are insufficient to determine if there is a drug-associated risk of miscarriage (see Data ) . In animal reproduction studies, no adverse developmental effects were observed in pregnant rats or rabbits orally administered simvastatin during the period of organogenesis at doses that resulted in 2.5 and 2 times, respectively, the human exposure at the maximum recommended human dosage of 80 mg/day, based on body surface area (mg/m 2 ).
In animal reproduction studies, no adverse developmental effects were observed in pregnant rats and rabbits orally administered ezetimibe during the period of organogenesis at doses that resulted in up to 10 and 150 times, respectively, the human exposure at the MRHD, based on AUC (see Data ). The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2 to 4% and 15 to 20%, respectively.
Data Human Data Ezetimibe There are insufficient data on ezetimibe use in pregnant women to evaluate for a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes. Simvastatin A Medicaid cohort linkage trial of 1152 statin-exposed pregnant women compared to 886,996 controls did not find a significant teratogenic effect from maternal use of statins in the first trimester of pregnancy, after adjusting for potential confounders – including maternal age, diabetes mellitus, hypertension, obesity, and alcohol and tobacco use – using propensity score-based methods.
The relative risk of congenital malformations between the group with statin use and the group with no statin use in the first trimester was 1.07 (95% confidence interval 0.85 to 1.37) after controlling for confounders, particularly pre-existing diabetes mellitus. There were also no statistically significant increases in any of the organ-specific malformations assessed after accounting for confounders. In the majority of pregnancies, statin treatment was initiated prior to pregnancy and was discontinued at some point in the first trimester when pregnancy was identified.
Trial limitations include reliance on physician coding to define the presence of a malformation, lack of control for certain confounders such as body mass index, use of prescription dispensing as verification for the use of a statin, and lack of information on non-live births. Animal Data Ezetimibe In oral (gavage) embryo-fetal development studies of ezetimibe conducted in rats (gestation days 6-15) and rabbits (gestation days 7-19), there was no evidence of maternal toxicity or embryolethality at any dose tested (250, 500, 1000 mg/kg/day) at exposure equivalent to 10 to 150 times the clinical exposure, based on AUC, in rats and rabbits.
In rats, increased incidences of common fetal skeletal findings (extra pair of thoracic ribs, unossified cervical vertebral centra, shortened ribs) were observed at 1000 mg/kg/day (~10 times the human exposure at 10 mg daily based on AUC 0-24hr for total ezetimibe). In rabbits treated with ezetimibe, an increased incidence of extra thoracic ribs was observed at 1000 mg/kg/day (150 times the human exposure at 10 mg daily based on AUC 0-24hr for total ezetimibe).
The animal-to-human exposure multiple for total ezetimibe at the no-observed effect level was 6 times for rat and 134 times for rabbit. Fetal exposure to ezetimibe (conjugated and unconjugated) was confirmed in subsequent placental transfer studies conducted using a maternal dose of 1000 mg/kg/day. The fetal maternal plasma exposure ratio (total ezetimibe) was 1.5 for rats on gestation day 20 and 0.03 for rabbits on gestation day 22.
The effect of ezetimibe on prenatal and postnatal development and maternal function was evaluated in pregnant rats at doses of 100, 300 or 1000 mg/kg/day (gestation day 6 through lactation day 21). No maternal toxicity or adverse developmental outcomes were observed up to and including the highest dose tested (17 times the human exposure at 10 mg daily based on AUC 0-24hr for total ezetimibe). Multiple-dose studies of ezetimibe given in combination with statins in rats and rabbits during organogenesis resulted in higher ezetimibe and statin exposures.
Reproductive findings occurred at lower doses in combination therapy compared to monotherapy. Simvastatin Simvastatin was given to pregnant rats at doses of 6.25, 12.5 and 25 mg/kg/day (0.6 times, 1.3 times, and 2.5 times, respectively, the maximum recommended dosage of 80 mg/day when normalized to body surface area) from gestation days 6-17 and to pregnant rabbits from gestation days 6-18 at doses of 2.5, 5, and 10 mg/kg/day (0.5 times, 1 times, and 2 times, respectively, the maximum recommended dosage of 80 mg/day when normalized to body surface area).
For both species, there was no evidence of maternal toxicity, or embryolethality. In rats, mean fetal body weights in the 25 mg/kg/day group were decreased 5.4%. Similar fetal body weight effects were not observed in rabbits. Simvastatin doses of 6.25, 12.5 and 25 mg/kg/day (0.6 times, 1.3 times, and 2.5 times, respectively, the maximum recommended dosage of 80 mg/day when normalized to body surface area) were given to pregnant rats from gestation day 15 to lactation day 21.
Slight decreases in maternal body weight gain and pup postnatal day 0 weight were observed in the 25 mg/kg/day dose group. Mean body weight gain of pups during lactation was slightly decreased at doses ≥12.5 mg/kg/day. Post weaning weight, behavior, reproductive performance and fertility of the offspring were not affected at any dose tested. Placental transfer of simvastatin was not evaluated in rats or rabbits. However, it has been shown that other drugs in this class cross the placenta.
