8.1Pregnancy Risk Summary
Teriflunomide tablets are contraindicated for use in pregnant women and females of reproductive potential not using effective contraception because of the potential for fetal harm based on animal data. Human data are not available at this time to inform the presence or absence of drug-associated risk with the use of teriflunomide tablets during pregnancy. In animal reproduction studies in rat and rabbits, oral administration of teriflunomide during organogenesis caused teratogenicity and embryolethality at plasma exposures (AUC) lower than that at the maximum human recommended dose (MHRD) of 14 mg/day [see Data].
In the US 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. The background risk of major birth defects and miscarriage in the indicated population is unknown. Clinical Considerations Women who wish to become pregnant should discontinue use of teriflunomide tablets and undergo an accelerated elimination procedure to decrease the plasma concentration of teriflunomide to less than 0.02 mg/L (0.02 mcg/mL).
Effective contraception should be used until is it verified that plasma concentrations of teriflunomide are less than 0.02 mg/L (0.02 mcg/mL) [see Warnings and Precautions (5.3)] . Human plasma concentrations of teriflunomide less than 0.02 mg/L (0.02 mcg/mL) are expected to have minimal embryofetal risk [see Contraindications (4) and Warnings and Precautions (5.3)] . If the patient becomes pregnant while taking this drug, stop treatment with teriflunomide tablets, inform the patient of the potential risk to the fetus, and perform the accelerated drug elimination procedure to achieve plasma concentrations of less than 0.02 mg/L (0.02 mcg/mL) [see Warnings and Precautions (5.3) and Clinical Pharmacology (12.3)].
Refer the patient to an obstetrician/gynecologist, preferably experienced in reproductive toxicity, for further evaluation and counseling [see Warnings and Precautions (5.2, 5.3)]. Data Animal Data When teriflunomide (oral doses of 1, 3, or 10 mg/kg/day) was administered to pregnant rats throughout the period of organogenesis, high incidences of fetal malformation (primarily craniofacial, and axial and appendicular skeletal defects) and embryofetal death were observed at doses not associated with maternal toxicity.
Adverse effects on embryofetal development were observed following dosing at various stages throughout organogenesis. Maternal plasma exposure at the no-effect level (1 mg/kg/day) for embryofetal developmental toxicity in rats was less than that in humans at the maximum recommended human dose (MRHD, 14 mg/day). Administration of teriflunomide (oral doses of 1, 3.5, or 12 mg/kg/day) to pregnant rabbits throughout organogenesis resulted in high incidences of fetal malformation (primarily craniofacial, and axial and appendicular skeletal defects) and embryofetal death at doses associated with minimal maternal toxicity.
Maternal plasma exposure at the no-effect dose (1 mg/kg/day) for embryofetal developmental toxicity in rabbits was less than that in humans at the MRHD. In studies in which teriflunomide (oral doses of 0.05, 0.1, 0.3, 0.6, or 1 mg/kg/day) was administered to rats during gestation and lactation, decreased growth, eye and skin abnormalities, and high incidences of malformation (limb defects) and postnatal death were observed in the offspring at doses not associated with maternal toxicity.
Maternal plasma exposure at the no-effect dose for pre-and postnatal developmental toxicity in rats (0.1 mg/kg/day) was less than that in humans at the MRHD. In animal reproduction studies of leflunomide, embryolethality and teratogenic effects were observed in pregnant rat and rabbit at or below clinically relevant plasma teriflunomide exposures (AUC). In published reproduction studies in pregnant mice, leflunomide was embryolethal and increased the incidence of malformations (craniofacial, axial skeletal, heart and great vessel).
Supplementation with exogenous uridine reduced the teratogenic effects in pregnant mice, suggesting that the mode of action (inhibition of mitochondrial enzyme dihydroorotate dehydrogenase) is the same for therapeutic efficacy and developmental toxicity. At recommended doses in humans, teriflunomide and leflunomide result in a similar range of plasma concentrations of teriflunomide.
