Mometasone

No formal drug-drug interaction studies have been conducted with mometasone furoate nasal spray. Inhibitors of Cytochrome P450 3A4: Studies have shown that mometasone furoate is primarily and extensively metabolized in the liver of all species investigated and undergoes extensive metabolism to multiple metabolites. In vitro studies have confirmed the primary role of cytochrome CYP3A4 in the metabolism of this compound. Concomitant administration of CYP3A4 inhibitors may inhibit the metabolism of, and increase the systemic exposure to, mometasone furoate and potentially increase the risk for systemic corticosteroid side effects.

Caution should be exercised when considering the coadministration of mometasone furoate nasal spray with long-term ketoconazole and other known strong CYP3A4 inhibitors (e.g., ritonavir, cobicistat-containing products, atazanavir, clarithromycin, indinavir, itraconazole, nefazodone, nelfinavir, saquinavir, telithromycin) [see Clinical Pharmacology ( 12.3 )]. Consider the benefit of coadministration versus the potential risk of systemic corticosteroid effects, in which case patients should be monitored for systemic corticosteroid side effects.

8.1 Pregnancy Risk Summary Mometasone is minimally absorbed systemically following nasal use, and maternal use is not expected to result in fetal exposure to the drug. Available data from observational studies of mometasone use in pregnant women are insufficient to evaluate for a drug-associated risk of major birth defects, miscarriage or other adverse maternal or fetal outcomes.

In animal reproduction studies with pregnant mice, rats, or rabbits (subcutaneous, subcutaneous/topical dermal/oral, and topical dermal/oral, respectively), mometasone furoate caused increased fetal malformations and decreased fetal survival and growth following administration of doses that produced exposures approximately 1/3 to 8 times the maximum recommended human dose (MRHD) on a mcg/m 2 or AUC basis [see Data]. However, experience with oral corticosteroids suggests that rodents are more prone to teratogenic effects from corticosteroid exposure than humans. The estimated 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 risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively.

Data Animal Data In an embryofetal development study with pregnant mice dosed throughout the period of organogenesis, mometasone furoate produced cleft palate at a dose less than the maximum recommended daily intranasal dose (MRDID) (on a mcg/m 2 basis with maternal subcutaneous doses of 60 mcg/kg and above) and decreased fetal survival at approximately 2 times the MRDID (on a mcg/m 2 basis with a maternal subcutaneous dose of 180 mcg/kg). No toxicity was observed with a dose that produced an exposure less than the MRDID (on a mcg/m 2 basis with maternal topical dermal doses of 20 mcg/kg and above).

In an embryofetal development study with pregnant rats dosed throughout the period of organogenesis, mometasone furoate produced fetal umbilical hernia at exposures approximately 10 times the MRDID (on a mcg/m 2 basis with maternal topical dermal doses of 600 mcg/kg and above) and delays in fetal ossification at a dose approximately 6 times the MRDID (on a mcg/m 2 basis with maternal topical dermal doses of 300 mcg/kg and above). In another reproductive toxicity study, pregnant rats were dosed with mometasone furoate throughout pregnancy or late in gestation. Treated animals had prolonged and difficult labor, fewer live births, lower birth weight, and reduced early…

8.2 Lactation Risk Summary There are no available data on the presence of mometasone furoate nasal spray in human milk, the effects on the breastfed child, or the effects on milk production. However, mometasone is minimally absorbed systemically by the mother following nasal use, and breastfeeding is not expected to result in exposure of the infant to mometasone. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for mometasone furoate nasal spray and any potential adverse effects on the breastfed infant from mometasone furoate nasal spray or from the underlying maternal condition.