Pitolisant

Strong CYP2D6 Inhibitors: Increased exposure of WAKIX; reduce the maximum recommended dose of WAKIX by half ( 2.6 , 7.1 ) Strong CYP3A4 Inducers: Decreased exposure of WAKIX; consider dosage adjustment of WAKIX ( 2.6 , 7.1 ) Sensitive CYP3A4 Substrates (including hormonal contraceptives): WAKIX may reduce effectiveness of sensitive CYP3A4 substrates. Use an alternative non-hormonal contraceptive method during treatment with WAKIX and for at least 21 days after discontinuation of treatment ( 7.1 , 8.3 )

7.1 Drugs Having Clinically Important Interactions with WAKIX Table 2: Clinically Significant Drug Interactions with WAKIX Effect of Other Drugs on WAKIX Strong CYP2D6 Inhibitors Clinical Implication: Concomitant administration of WAKIX with strong CYP2D6 inhibitors increases pitolisant exposure by 2.2-fold. Prevention or Management: Reduce the dose of WAKIX by half [see see Dosage and Administration ( 2.6 ), Clinical Pharmacology ( 12.3 )] . Strong CYP3A4 Inducers Clinical Implication: Concomitant use of WAKIX with strong CYP3A4 inducers decreases exposure of pitolisant by 50%. Prevention or Management: Assess for loss of efficacy after initiation of a strong CYP3A4 inducer.

For patients stable on WAKIX 8.9 mg or 17.8 mg once daily, increase the dose of WAKIX to reach double the original daily dose (i.e., 17.8 mg or 35.6 mg, respectively) over 7 days. If concomitant dosing of a strong CYP3A4 inducer is discontinued, decrease WAKIX dosage by half [see see Dosage and Administration ( 2.6 ), Clinical Pharmacology ( 12.3 )] . Histamine-1 (H1) Receptor Antagonists Clinical Implication: WAKIX increases the levels of histamine in the brain; therefore, H1 receptor antagonists that cross the blood-brain barrier may reduce the effectiveness of WAKIX. Prevention or Management: Avoid centrally acting H1 receptor antagonists.

QT Interval Prolongation Clinical Implication: Concomitant use of drugs that prolong the QT interval may add to the QT effects of WAKIX and increase the risk of cardiac arrhythmia. Prevention or Management: Avoid the use of WAKIX in combination with other drugs known to prolong the QT interval [see Warnings and Precautions ( 5.1 )] . Effect of WAKIX on Other Drugs Sensitive CYP3A4 Substrates Clinical Implication: WAKIX is a borderline/weak inducer of CYP3A4. Therefore, reduced effectiveness of sensitive CYP3A4 substrates may occur when used concomitantly with WAKIX [see Clinical Pharmacology ( 12.3 )] .

The effectiveness of hormonal contraceptives (e.g., ethinyl estradiol) may be reduced when used with WAKIX and effectiveness may be reduced for 21 days after discontinuation of therapy. Prevention or Management: Patients using hormonal contraception should be advised to use an alternative non-hormonal contraceptive method during treatment with WAKIX and for at least 21 days after discontinuation of treatment [see Use in Specific Populations ( 8.3 )].

8.1 Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women who are exposed to WAKIX during pregnancy. Patients should be encouraged to enroll in the WAKIX pregnancy registry if they become pregnant. To enroll or obtain information from the registry, patients can call 1-800-833-7460. Risk Summary Available case reports from clinical trials and postmarketing reports with WAKIX use in pregnant women have not determined a drug-associated risk of major birth defects, miscarriage or adverse maternal or fetal outcomes.

In animal reproductive studies, administration of pitolisant during organogenesis caused maternal and embryofetal toxicity in rats and rabbits at doses ≥13 and >4 times the maximum recommended human dose (MRHD) of 35.6 mg based on mg/m 2 body surface area, respectively. Oral administration of pitolisant to female rats during pregnancy and lactation adversely affected maternal and fetal health and produced developmental delay at doses ≥13 times the MRHD, based on mg/m 2 body surface area and increased the incidence of major malformations at 22 times the MRHD (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 Pitolisant was administered orally to pregnant rats during the period of organogenesis at doses of 30, 52, 90 and 110 mg/kg/day, which are approximately 7, 13, 22 and 27 times the MRHD, based on mg/m2 body surface area, respectively. Maternal toxicity occurred at >22 times the MRHD and included convulsions and decreases in body weight and food consumption.

At these maternally toxic doses, no adverse effects on embryofetal development were noted and the no observed-adverse-effect-level for embryofetal toxicity is 27 times the MRHD based on mg/m 2 body surface area. Pitolisant was administered intramuscularly to pregnant rabbits during the period of organogenesis at doses of 4, 8, and 16 mg/kg/day, which are approximately 2, 4 and 8 times the MRHD, based on mg/m 2 body surface area, respectively. Maternal toxicity occurred at ≥4 times the MRHD and included significant body weight loss and decreased food consumption. Mortality (1 animal) and convulsions (2 animals) occurred at 8 times the MRHD. At the maternally toxic dose (8…