Olopatadine (nasal)

Formal drug-drug interaction studies were not conducted for olopatadine hydrochloride nasal spray. Drug interactions with inhibitors of liver enzymes are not anticipated because olopatadine is eliminated predominantly by renal excretion. Drug interactions involving P450 inhibition and plasma protein binding are also not expected [ See Clinical Pharmacology ( 12.3 ) ].

8.1 Pregnancy Risk Summary Published data from postmarketing experience with antihistamines, with similar mechanism of action to olopatadine hydrochloride nasal spray, have not identified a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes. However, there are no published human data specific to olopatadine hydrochloride nasal spray. In animal reproductive studies, oral administration of olopatadine hydrochloride to pregnant rats and rabbits caused a decrease in the number of live fetuses at maternal doses approximately 110 and 1460 times the maximum recommended human daily intranasal dose (MRHDID) on a mg/m 2 basis, respectively (see Data) .

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 background 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 oral embryo-fetal development study, pregnant rabbits were dosed throughout the period of organogenesis at doses up to 400 mg/kg/day. A decrease in the number of live fetuses was observed at 400 mg/kg/day (1460 times the MRHDID, on a mg/m 2 basis).

In an oral embryo-fetal development study, pregnant rats were dosed throughout the period of organogenesis at doses up to 600 mg/kg/day. Maternal toxicity, producing death and reduced maternal body weight gain was observed at 600 mg/kg/day (approximately 1100 times the MRHDID on a mg/m 2 basis). Olopatadine produced cleft palate at 60 mg/kg/day (approximately 110 times the MRHDID on a mg/m 2 basis) and decreased embryo-fetal viability and reduced fetal weight in rats at 600 mg/kg/day (approximately 1100 times the MRHDID on a mg/m 2 basis).

In peri-/postnatal toxicity studies, pregnant rats received oral doses of olopatadine up to 600 mg/kg/day during late gestation and throughout the lactation period. Olopatadine produced decreased neonatal survival at 60 mg/kg/day (approximately 110 times the MRHDID on a mg/m 2 basis) and reduced body weight gain in pups at 4 mg/kg/day (approximately 7 times the MRHDID on a mg/m 2 basis). These effects appeared attributable to exposure of pups via the milk as demonstrated in a cross-fostered study in which pups of untreated dams cross-fostered to dams treated with 60 mg/kg/day olopatadine orally during the lactation period exhibited decreased body weight gain.