Eszopiclone (oral mucosal)

7 DRUG INTERACTIONS • CNS Depressants: Additive CNS-depressant effects with combination use. Use with ethanol causes additive psychomotor impairment ( 7.1 ) • Rifampicin: Combination use may decrease exposure and effects of eszopiclone ( 7.2 ) • Ketoconazole: Combination use increases exposure and effect of eszopiclone. Dose reduction of eszopiclone is needed ( 7.2 )

7.1 CNS Active Drugs Ethanol: An additive effect on psychomotor performance was seen with coadministration of eszopiclone and ethanol [see Warnings and Precautions ( 5.1 , 5.2 )] . Olanzapine: Coadministration of eszopiclone and olanzapine produced a decrease in DSST scores. The interaction was pharmacodynamic; there was no alteration in the pharmacokinetics of either drug.

7.2 Drugs that Inhibit or Induce CYP3A4 Drugs that Inhibit CYP3A4 (Ketoconazole) CYP3A4 is a major metabolic pathway for elimination of eszopiclone. The exposure of eszopiclone was increased by coadministration of ketoconazole, a potent inhibitor of CYP3A4. Other strong inhibitors of CYP3A4 (e.g., itraconazole, clarithromycin, nefazodone, troleandomycin, ritonavir, nelfinavir) would be expected to behave similarly. Dose reduction of eszopiclone is needed for patients co administered eszopiclone with potent CYP3A4 inhibitors [see Dosage and Administration ( 2.3 )].

Drugs that Induce CYP3A4 (Rifampicin) Racemic zopiclone exposure was decreased 80% by concomitant use of rifampicin, a potent inducer of CYP3A4. A similar effect would be expected with eszopiclone. Combination use with CYP3A4 inducer may decrease the exposure and effects of eszopiclone. Drug Interactions Eszopiclone is metabolized by CYP3A4 and CYP2E1 via demethylation and oxidation. There were no pharmacokinetic or pharmacodynamic interactions between eszopiclone and paroxetine.

When eszopiclone was coadministered with olanzapine, no pharmacokinetic interaction was detected in levels of eszopiclone or olanzapine, but a pharmacodynamic interaction was seen on a measure of psychomotor function. Eszopiclone and lorazepam decreased each other’s C max by 22%. Coadministration of eszopiclone 3 mg to subjects receiving ketoconazole, a potent inhibitor of CYP3A4, 400 mg daily for 5 days, resulted in a 2.2-fold increase in exposure to eszopiclone. C max and t 1/2 were increased 1.4-fold and 1.3-fold, respectively.

Eszopiclone would not be expected to alter the clearance of drugs metabolized by common CYP450 enzymes [see Warnings and Precautions ( 5.7 ), Dosage and Administration ( 2.3 )] . Paroxetine: Coadministration of single dose of eszopiclone and paroxetine produced no pharmacokinetic or pharmacodynamic interaction. The lack of a drug interaction following single-dose administration does not predict the complete absence of a pharmacodynamic effect following chronic administration. Lorazepam: Coadministration of single doses of eszopiclone and lorazepam did not have clinically relevant effects on the pharmacodynamics or pharmacokinetics of either drug.

The lack of a drug interaction following single-dose administration does not predict the complete absence of a pharmacodynamic effect following chronic administration.

8.1 Pregnancy Risk Summary Available pharmacovigilance data with eszopiclone use in pregnant women are insufficient to identify a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes. In animal reproduction studies conducted in pregnant rats and rabbits throughout organogenesis, there was no evidence of teratogenicity. Administration of eszopiclone to rats throughout pregnancy and lactation resulted in offspring toxicities at all doses tested; the lowest dose was approximately 200 times the maximum recommended human dose (MRHD) of 3 mg/day based on mg/m 2 body surface area (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 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 Oral administration of eszopiclone to pregnant rats (62.5, 125, or 250 mg/kg/day) and rabbits (4, 8, or 16 mg/kg/day) throughout organogenesis showed no evidence of teratogenicity up to the highest doses tested.

In rats, reduced fetal weight and increased incidences of skeletal variations and/or delayed ossification were observed at the mid and high doses. The no-observed-effect dose for adverse effects on embryofetal development is 200 times the MRHD of 3 mg/day on a mg/m 2 basis. No effects on embryofetal development were observed in rabbits; the highest dose tested is approximately 100 times the MRHD on a mg/m 2 basis. Oral administration of eszopiclone (60, 120, or 180 mg/kg/day) to pregnant rats throughout the pregnancy and lactation resulted in increased post-implantation loss, decreased postnatal pup weights and survival, and increased pup startle response at all doses.

The lowest dose tested is approximately 200 times the MRHD on a mg/m 2 basis. Eszopiclone had no effects on other developmental measures or reproductive function in the offspring.