Pitolisant Hydrochloride

1 INDICATIONS AND USAGE WAKIX is indicated for the treatment of excessive daytime sleepiness (EDS) or cataplexy in patients 6 years of age and older with narcolepsy. WAKIX is a histamine-3 (H3) receptor antagonist/inverse agonist indicated for the treatment of excessive daytime sleepiness (EDS) or cataplexy patients 6 years of age and older with narcolepsy ( 1 )

2 DOSAGE AND ADMINISTRATION See Full Prescribing Information for complete dosage instructions ( 2.2 , 2.3 ) Administer orally once daily in the morning upon wakening ( 2.2 , 2.3 ) Dosage Recommendations: Adults ( 2.2 ) Week 1 Initiate with a dosage of 8.9 mg once daily Week 2 Increase dosage to 17.8 mg once daily Week 3 May increase to the maximum recommended dosage of 35.6 mg once daily Pediatric Patients (6 years and older) ( 2.3 ) Week 1 Initiate with a dosage of 4.45 mg once daily Week 2 Increase dosage to 8.9 mg once daily Week 3 Increase dosage to 17.8 mg once daily, the maximum recommended dosage for patients weighing <40 kg Week 4 For patients weighing ≥40 kg, may increase to the maximum recommended dosage of 35.6 mg once daily Hepatic impairment ( 2.4 , 8.6 , 12.3 ): Moderate hepatic impairment (Child-Pugh Class B): Adults: Initial dosage is 8.9 mg once daily. Increase to a maximum dosage of 17.8 mg once daily after 14 days Pediatric Patients: Initial dosage is 4.45 mg once daily. Increase to 8.9 mg once daily after 14 days; for patients weighing ≥40 kg, may increase to 17.8 mg once daily after another 14 days Renal impairment (eGFR less than 60 mL/minute/1.73 m 2 ) ( 2.5 , 8.7 , 12.3 ): Adults: Initial dosage is 8.9 mg once daily. Increase to a maximum dosage of 17.8 mg once daily after 7 days Pediatric Patients: Initial dosage is 4.45 mg once daily.Increase to 8.9 mg once daily after 7 days; for patients weighing ≥40 kg, may increase to 17.8 mg once daily after another 7 days End-stage renal disease (ESRD): Not recommended Poor Metabolizers of CYP2D6 ( 2.7 ): Adults: Maximum recommended dosage is 17.8 mg once daily Pediatric Patients: Maximum recommended dosage is 8.9 mg once daily for patients weighing <40 kg and 17.8 mg for patients weighing ≥40 kg 2.1 Recommendations Prior to WAKIX Initiation Consider genotyping patients for CYP2D6 metabolizer status to determine the maximum recommended dosage [see Dosage and Administration ( 2.7 )]. 2.2 Recommended Dosage in Adult Patients The recommended dosage range for WAKIX for the treatment of EDS or cataplexy in adult patients is 17.8 mg to 35.6 mg administered orally once daily in the morning upon wakening. Titrate dosage as follows: Week 1: Initiate with a dosage of 8.9 mg (two 4.45 mg tablets) once daily Week 2: Increase dosage to 17.8 mg (one 17.8 mg tablet) once daily Week 3: May increase to the maximum recommended dosage of 35.6 mg (two 17.8 mg tablets) once daily Dose may be adjusted based on tolerability.If a dose is missed, patients should take the next dose the following day in the morning upon wakening.It may take up to 8 weeks for some patients to achieve a clinical response. 2.3 Recommended Dosage in Pediatric Patients 6 Years and Older The recommended starting dosage of WAKIX for the treatment of EDS or cataplexy in pediatric patients 6 years and older is 4.45 mg administered orally once daily in the morning upon wakening. Titrate dosage as follows: Week 1: Initiate with a dosage of 4.45 mg (one 4.45 mg tablet) once daily Week 2: Increase dosage to 8.9 mg (two 4.45 mg tablets) once daily Week 3: Increase dosage to 17.8 mg (one 17.8 mg tablet) once daily, which is the maximum recommended dosage for patients weighing <40 kg Week 4: For patients weighing ≥40 kg, may increase to the maximum recommended dosage of 35.6 mg (two 17.8 mg tablets) once daily Dose may be adjusted based on tolerability. If a dose is missed, patients should take the next dose the following day in the morning upon wakening. It may take up to 8 weeks for some patients to achieve a clinical response. 2.4 Dosage Recommendations in Patients with Hepatic Impairment Adult Patients with Moderate (Child-Pugh Class B) Hepatic Impairment Initiate WAKIX at 8.9 mg once daily and increase after 14 days to a maximum recommended dosage of 17.8 mg once daily [see Warnings and Precautions ( 5.1 ), Use in Specific Populations ( 8.6 ), Clinical Pharmacology ( 12.3 )] . Pediatric Patients (6 years and older) with Moderate (Child-Pugh Class B) Hepatic Impairment Pediatric patients weighing <40 kg: Initiate WAKIX at 4.45 mg once daily and increase after 14 days to a maximum recommended dosage of 8.9 mg once daily [see Warnings and Precautions ( 5.1 ), Use in Specific Populations ( 8.6 ), Clinical Pharmacology ( 12.3 )] . Pediatric patients weighing ≥40 kg: Initiate WAKIX at 4.45 mg once daily and increase after 14 days to 8.9 mg once daily. May increase after another 14 days to a maximum recommended dosage of 17.8 mg once daily [see Warnings and Precautions ( 5.1 ), Use in Specific Populations ( 8.6 ), Clinical Pharmacology ( 12.3 )] . WAKIX is contraindicated in patients with severe hepatic impairment. WAKIX has not been studied in patients with severe hepatic impairment [see Contraindications ( 4 ), Warnings and Precautions ( 5.1 ), Use in Specific Populations ( 8.6 ), Clinical Pharmacology ( 12.3 )] . 2.5 Dosage Recommendations in Patients with Renal Impairment and End-Stage Renal Disease Adult Patients with eGFR <60 mL/minute/1.73 m 2 Initiate WAKIX at 8.9 mg once daily and increase after 7 days to a maximum recommended dosage of 17.8 mg once daily [see Warnings and Precautions ( 5.1 ), Use in Specific Populations ( 8.7 ), Clinical Pharmacology ( 12.3 )] . Pediatric Patients (6 years and older) with eGFR <60 mL/minute/1.73 m 2 (using the Schwartz equation, eGFR (mL/min/1.73 m2)=(0.413*height in cm)/serum creatinine in mg/dL) Pediatric patients weighing <40 kg: Initiate WAKIX at 4.45 mg once daily and increase after 7 days to a maximum recommended dosage of 8.9 mg once daily [see Warnings and Precautions ( 5.1 ), Use in Specific Populations ( 8.7 ), Clinical Pharmacology ( 12.3 )] . Pediatric patients weighing ≥40 kg: Initiate WAKIX at 4.45 mg once daily and increase after 7 days to 8.9 mg once daily. May increase after another 7 days to a maximum recommended dosage of 17.8 mg once daily [see Warnings and Precautions ( 5.1 ), Use in Specific Populations ( 8.7 ), Clinical Pharmacology ( 12.3 )] . WAKIX is not recommended in patients with eGFR less than 15 mL/minute/1.73 m 2 [see Warnings and Precautions ( 5.1 ), Use in Specific Populations ( 8.7 ), Clinical Pharmacology ( 12.3 )] . 2.6 Dosage Modifications for Concomitant Use with Strong CYP2D6 Inhibitors and Strong CYP3A4 Inducers Coadministration with Strong CYP2D6 Inhibitors Adult patients: Initiate WAKIX at 8.9 mg once daily and increase after 7 days to a maximum recommended dosage of 17.8 mg once daily [see Drug Interactions ( 7.1 ), Clinical Pharmacology ( 12.3 )] . Pediatric patients (6 years and older) weighing <40 kg: Initiate WAKIX at 4.45 mg once daily and increase after 7 days to a maximum recommended dosage of 8.9 mg once daily [see Drug Interactions ( 7.1 ), Clinical Pharmacology ( 12.3 )] . Pediatric patients (6 years and older) weighing ≥40 kg: Initiate WAKIX at 4.45 mg once daily and increase after 7 days to 8.9 mg once daily. May increase after another 7 days to a maximum recommended dosage of 17.8 mg once daily [see Drug Interactions ( 7.1 ), Clinical Pharmacology ( 12.3 )] . Adult and pediatric patients on a stable dose of WAKIX: Reduce the WAKIX dose by half upon initiating strong CYP2D6 inhibitors [see Drug Interactions ( 7.1 ), Clinical Pharmacology ( 12.3 )] . Coadministration with Strong CYP3A4 Inducers Concomitant use of WAKIX with strong CYP3A4 inducers decreases pitolisant exposure by 50%. Assess for loss of efficacy after initiation of a strong CYP3A4 inducer. For adult and pediatric patients stable on WAKIX 8.9 mg or 17.8 mg once daily, increase the dose of WAKIX to 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 Drug Interactions ( 7.1 ), Clinical Pharmacology ( 12.3 )] . 2.7 Dosage Recommendations in Patients Who Are CYP2D6 Poor Metabolizers Adult Patients Initiate WAKIX at 8.9 mg once daily and increase after 7 days to a maximum recommended dosage of 17.8 mg once daily [see Use in Specific Populations ( 8.8 ), Clinical Pharmacology ( 12.5 )] . Pediatric patients Pediatric patients (6 years and older) weighing <40 kg: Initiate WAKIX at 4.45 mg once daily and increase after 7 days to a maximum recommended dosage of 8.9 mg once daily [see Use in Specific Populations ( 8.8 ), Clinical Pharmacology ( 12.5 )] . Pediatric patients (6 years and older) weighing ≥40 kg: Initiate WAKIX at 4.45 mg once daily and increase after 7 days to 8.9 mg once daily. May increase after another 7 days to a maximum recommended dosage of 17.8 mg once daily [see Use in Specific Populations ( 8.8 ), Clinical Pharmacology ( 12.5 )] .

6 ADVERSE REACTIONS The following adverse reactions are discussed in more detail in other sections of the labeling: QT Interval Prolongation [see Warnings and Precautions ( 5.1 )] Most common adverse reactions (≥5% and at least twice placebo) in adults: insomnia, nausea, and anxiety ( 6.1 ). Most common adverse reactions (≥5% and greater than placebo) in pediatric patients 6 years and older: headache and insomnia ( 6.1 ). To report SUSPECTED ADVERSE REACTIONS, contact Harmony Biosciences at 1-800-833-7460 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Adult Patients with Narcolepsy In clinical trials for narcolepsy, 172 adult patients were treated with WAKIX in placebo-controlled trials for up to 8 weeks and in open-label extension trials for up to 5 years. In trials in which WAKIX was directly compared to placebo, 6 of the 152 patients (3.9%) who received WAKIX and 4 of the 114 patients (3.5%) who received placebo discontinued because of an adverse reaction. Most Common Adverse Reactions In the placebo-controlled clinical trials conducted in patients with narcolepsy with or without cataplexy, the most common adverse reactions (occurring in ≥5% of patients and at least twice the rate of placebo) with the use of WAKIX were insomnia (6%), nausea (6%), and anxiety (5%). Table 1 presents the adverse reactions that occurred at a rate of ≥2% in patients treated with WAKIX and more frequently than in patients treated with placebo in the placebo-controlled clinical trials in narcolepsy. Table 1: Adverse Reactions that Occurred in ≥2% of WAKIX-Treated Patients and More Frequently than in Placebo-Treated Patients in Three Placebo-Controlled Narcolepsy Studies * The following terms were combined: Abdominal pain includes: abdominal discomfort; abdominal pain; abdominal pain upper Anxiety includes: anxiety; nervousness; stress; stress at work Hallucinations includes: hallucination; hallucination visual; hypnagogic hallucination Headache includes: cluster headache; headache; migraine; premenstrual headache; tension headache Heart rate increased includes: heart rate increased; sinus tachycardia; tachycardia Insomnia includes: initial insomnia; insomnia; middle insomnia; poor quality sleep Musculoskeletal pain includes: arthralgia; back pain; carpal tunnel syndrome; limb discomfort; musculoskeletal pain; myalgia; neck pain; osteoarthritis; pain in extremity; sciatica Rash includes: eczema; erythema migrans; rash; urticaria Sleep disturbance includes: dyssomnia; sleep disorder; sleep paralysis; sleep talking Upper respiratory tract infection includes: pharyngitis; rhinitis; sinusitis; upper respiratory tract infection; upper respiratory tract inflammation; viral upper respiratory tract infection Adverse Reaction WAKIX (n=152) % Placebo (n=114) % Headache * 18 15 Insomnia * 6 2 Nausea 6 3 Upper respiratory tract infection * 5 3 Musculoskeletal pain * 5 3 Anxiety * 5 1 Heart rate increased * 3 0 Hallucinations * 3 0 Irritability 3 2 Abdominal pain * 3 1 Sleep disturbance * 3 2 Decreased appetite 3 0 Cataplexy 2 1 Dry mouth 2 1 Rash * 2 1 Pediatric Patients (6 years and older) with Narcolepsy In a clinical trial for narcolepsy, 73 pediatric patients 6 years and older were treated with WAKIX in the placebo-controlled phase for up to 8 weeks and 105 patients in the open-label extension phase for up to 8 years. Most Common Adverse Reactions In the placebo-controlled phase of the study, the most common adverse reactions (occurring in ≥5% of patients and greater than the rate of placebo) with the use of WAKIX were headache (19%) and insomnia (7%). The overall adverse reaction profile of WAKIX in the pediatric clinical trial was similar to that seen in the adult clinical trial program. 6.2 Postmarketing Experience The following adverse reactions have been identified during post-approval use of WAKIX. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure: General disorders and administration site conditions: fatigue Immune system disorders: hypersensitivity (anaphylaxis) Investigations: weight increased Nervous system disorders: dizziness, epilepsy Psychiatric disorders: abnormal behavior, abnormal dreams, anhedonia, bipolar disorder, depression, depressed mood, nightmare, sleep disorder, suicide attempt, suicidal ideation Skin and subcutaneous tissue disorders: pruritus

12.3 Pharmacokinetics Following oral administration of pitolisant 35.6 mg once daily, the steady state C max and AUC are 73 ng/mL (range: 49.2 to 126 ng/mL) and 812 ng*hr/mL (range: 518 to 1468 ng*hr/mL), respectively. Pitolisant exposure (C max and AUC) increases proportionally with dose and steady state is reached by day 7. Absorption The median time to maximum plasma concentration (T max ) of pitolisant is 3.5 hours (2 to 5 hours). The oral absorption of WAKIX is around 90%. Food Effect No clinically significant differences in the pharmacokinetics of pitolisant were observed following administration with a high-fat meal (approximately 950 calories, 62% fat). Distribution The apparent volume of distribution of pitolisant is approximately 700 L (5 to 10 L/kg). Serum protein binding is approximately 91% to 96%. The blood to plasma ratio of pitolisant is 0.55 to 0.89. Elimination After a single dose of 35.6 mg, the median half-life of pitolisant is approximately 20 hours (7.5 to 24.2 hours). The apparent oral clearance (CL/F) of pitolisant is 43.9 L/hr and renal clearance accounts for <2% of the total clearance of pitolisant. Metabolism Pitolisant is primarily metabolized by CYP2D6 and to a lesser extent by CYP3A4; these metabolites are further metabolized or conjugated with glycine or glucuronic acid. None of these metabolites are pharmacologically active. Excretion After a single oral radiolabeled pitolisant 17.8 mg dose, approximately 90% of the dose was excreted in urine (<2% unchanged) and 2.3% in feces. Specific Populations No clinically significant differences in the pharmacokinetics of pitolisant were observed based on age (18 to 82 years old), sex, race/ethnicity (Caucasians or Blacks), or body weight (48 to 103 kg). The effects of end-stage renal disease and severe hepatic impairment on the pharmacokinetics of pitolisant are unknown. Pediatric Patients Pharmacokinetic data from 24 pediatric patients with narcolepsy (ages 7 to 17 years) receiving a single dose of WAKIX suggest that pediatric patients have higher exposure to pitolisant than adults. The geometric mean C max and AUC 0-10h of pitolisant were 2.2 and 2.0-fold higher, respectively, in pediatric patients 12 to 17 years and 3.4 and 3.6-fold higher, respectively, in pediatric patients 7 to 11 years compared to adults. Patients with Hepatic Impairment Six subjects with mild hepatic impairment (Child-Pugh Class A), 6 subjects with moderate hepatic impairment (Child-Pugh Class B), and 12 healthy subjects matched for age, sex, body mass index and ethnicity received a single dose of WAKIX 17.8 mg to assess the pharmacokinetics of WAKIX in patients with hepatic impairment. Exposure of pitolisant in patients with mild or moderate hepatic impairment is summarized in Figure 1 . No studies have been conducted in patients with severe hepatic impairment. Figure 1: Effect of Hepatic Impairment on Pitolisant Pharmacokinetics Dots = Geometric least squares mean ratios, Error bars = 90% CI; reference dashed lines are 0.8 and 1.25. AUC inf = area under the curve from time 0 to time infinity; C max = maximum plasma concentration. Patients with Renal Impairment A single dose of WAKIX 17.8 mg was administered to 4 subjects with mild renal impairment (eGFR of 60 to 89 mL/min/1.73 m 2 ), 4 subjects with moderate renal impairment (eGFR of 30 to 59 mL/min/1.73 m 2 ), 4 subjects with severe renal impairment (eGFR of 15 to 29 mL/min/1.73 m 2 ), and 12 subjects with normal renal function (i.e., eGFR >90 mL/min/1.73 m 2 ) to assess the pharmacokinetics of WAKIX in patients with renal impairment. Exposure of pitolisant in patients with mild, moderate, and severe renal impairment is summarized in Figure 2 . No studies have been conducted in patients with ESRD. Figure 2: Effect of Renal Impairment on Pitolisant Pharmacokinetics Dots = Geometric least squares mean ratios, Error bars = 90% CI; reference dashed lines are 0.8 and 1.25. AUC inf = area under the curve from time 0 to time infinity; C max = maximum plasma concentration. Drug-Drug Interactions Effect of Other Drugs on the Pharmacokinetics of WAKIX The effect of pitolisant on the pharmacokinetics of other drugs is presented in Figure 3 [see Dosage and Administration ( 2.6 , Drug Interactions ( 7.1 )] . Figure 3: Effect of Concomitant Medications on Pitolisant Dots = Geometric least squares mean ratios, Error bars = 90% CI; reference dashed lines are 0.8 and 1.25. AUC inf = area under the curve from time 0 to time infinity; C max = maximum plasma concentration. Effect of WAKIX on the Pharmacokinetics of Other Drugs The effect of pitolisant on the pharmacokinetics of other drugs is presented in Figure 4 [see Drug Interactions ( 7.1 ), Use in Specific Populations ( 8.3 )] . Figure 4: Effect of Pitolisant on Concomitant Medications Dots = Geometric least squares mean ratios, Error bars = 90% CI; reference dashed lines are 0.8 and 1.25. AUC inf = area under the curve from time 0 to time infinity; AUC 0-24 = area under the curve from time 0 to 24 hours; C max = maximum plasma concentration. Figure 1 Figure 2 Figure 3 Figure 4