Risk Summary

There are limited and incomplete human data from clinical trials and postmarketing reports on use of ORKAMBI or its individual components, lumacaftor or ivacaftor, in pregnant women to inform a drug-associated risk. In animal reproduction studies, oral administration of lumacaftor to pregnant rats and rabbits during organogenesis demonstrated no teratogenicity or adverse effects on fetal development at doses that produced maternal exposures up to approximately 8 (rats) and 5 (rabbits) times the exposure at the maximum recommended human dose (MRHD). Oral administration of ivacaftor to pregnant rats and rabbits during organogenesis demonstrated no teratogenicity or adverse effects on fetal development at doses that produced maternal exposures up to approximately 7 (rats) and 45 (rabbits) times the exposure at the MRHD. No adverse developmental effects were observed after oral administration of either lumacaftor or ivacaftor to pregnant rats from organogenesis through lactation at doses that produced maternal exposures approximately 8 and 5 times the exposures at the MRHD, respectively (see Data). There are no animal reproduction studies with concomitant administration of lumacaftor and ivacaftor. 

The 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

Animal Data

Lumacaftor

In an embryo-fetal development study in pregnant rats dosed during the period of organogenesis from gestation days 7-17, lumacaftor was not teratogenic and did not affect fetal development or survival at exposures up to 8 times the MRHD (on an AUC basis at maternal oral doses up to 2000 mg/kg/day). In an embryo-fetal development study in pregnant rabbits dosed during the period of organogenesis from gestation days 7-19, lumacaftor was not teratogenic and did not affect fetal development or survival at exposures up to 5 times the MRHD (on an AUC basis at maternal oral doses up to 200 mg/kg/day). In a pre- and post-natal development study in pregnant female rats dosed from gestation day 6 through lactation day 20, lumacaftor had no effects on delivery or growth and development of offspring at exposures up to 8 times the MRHD (on an AUC basis at maternal oral doses up to 1000 mg/kg/day). Placental transfer of lumacaftor was observed in pregnant rats and rabbits.

Ivacaftor

In an embryo-fetal development study in pregnant rats dosed during the period of organogenesis from gestation days 7-17, ivacaftor was not teratogenic and did not affect fetal survival at exposures up to 7 times the MRHD (based on summed AUCs for ivacaftor and its metabolites at maternal oral doses up to 200 mg/kg/day). In an embryo-fetal development study in pregnant rabbits dosed during the period of organogenesis from gestation days 7-19, ivacaftor was not teratogenic and did not affect fetal development or survival at exposures up to 45 times the MRHD (on an ivacaftor AUC basis at maternal oral doses up to 100 mg/kg/day). In a pre- and post-natal development study in pregnant female rats dosed from gestation day 7 through lactation day 20, ivacaftor had no effects on delivery or growth and development of offspring at exposures up to 5 times the MRHD (based on summed AUCs for ivacaftor and its metabolites at maternal oral doses up to 100 mg/kg/day). Decreased fetal body weights were observed at a maternally toxic dose that produced exposures 7 times the MRHD (based on summed AUCs for ivacaftor and its metabolites at a maternal oral dose of 200 mg/kg/day). Placental transfer of ivacaftor was observed in pregnant rats and rabbits.