Ketoconazole (topical)

8.1 Pregnancy Risk Summary There are no available data on ketoconazole foam, 2% use in pregnant women to identify a drug-associated risk of major birth defects, miscarriage or adverse maternal or fetal outcomes. No reproductive studies in animals have been performed with ketoconazole foam, 2%. In animal reproduction studies with pregnant mice, rats and rabbits both embryotoxic and developmental effects (structural abnormalities) were observed following oral dosing of ketoconazole during organogenesis.

Assuming equivalent systemic absorption of topical and oral ketoconazole doses and a ketoconazole foam, 2% maximum recommended human dose (MRHD) of 8 grams (equivalent to 160 mg ketoconazole), embryotoxic effects were observed at 0.8 to 2.4 times the MRHD and developmental effects were observed at 4.8 times the MRHD [see Data ] . The background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. 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 Animal Data The animal multiples of human exposure calculations are based on body surface area (BSA) comparisons of oral doses administered to animals and a ketoconazole foam, 2% maximum recommended human dose (MRHD) of 8 grams (equivalent to 2.67 mg ketoconazole/kg/day for a 60 kg individual or 98.8 mg ketoconazole/m 2 /day). Embryofetal development studies have been conducted in mice, rats and rabbits with orally administered ketoconazole.

When orally administered to mice on gestational days 6 through 18 (covering the period of organogenesis), ketoconazole was embryotoxic (25 mg/kg and higher; 0.8 times the MRHD based on BSA comparisons) with a high incidence of resorptions, increased number of stillbirths and delayed parturition. Delays in maturation were also observed. There was no evidence of maternal toxicity or malformations at up to 50 mg/kg (1.5 times the MRHD based on BSA comparisons). No treatment related developmental effects were observed at 10 mg/kg (0.3 times the MRHD based on BSA comparisons).

In the presence of maternal toxicity in rats, orally administered ketoconazole was both embryotoxic (40 mg/kg and higher; 2.4 times the MRHD based on BSA comparisons), including increased resorbed fetuses and stillbirths, and teratogenic (80 mg/kg and higher; 4.8 times the MRHD based on BSA comparisons), including syndactylia, oligodactylia, waved ribs and…