MONTELUKAST SODIUM

Montelukast sodium USP, the active ingredient in montelukast sodium tablets USP, is a selective and orally active leukotriene receptor antagonist that inhibits the cysteinyl leukotriene CysLT 1 receptor. Montelukast sodium USP is described chemically as [ R -( E )]-1-[[[1-[3-[2-(7-chloro-2-quinolinyl)ethenyl]phenyl]-3-[2-(1-hydroxy-1-methylethyl)phenyl]propyl]thio]methyl] cyclopropaneacetic acid, monosodium salt. The empirical formula is C 35 H 35 CINNaO 3 S, and its molecular weight is 608.17. The structural formula is: Montelukast sodium USP is a hygroscopic, optically active, white or almost white powder. Montelukast sodium USP is freely soluble in water and methylene chloride, freely soluble to very soluble in alcohol. Each 10 mg film-coated montelukast sodium tablet USP contains 10.4 mg montelukast sodium USP, which is equivalent to 10 mg of montelukast, and the following inactive ingredients: croscarmellose sodium, hydroxypropyl cellulose, lactose monohydrate, magnesium stearate, mannitol and microcrystalline cellulose. The tablets are coated with opadry yellow which contains carnauba wax, hydroxypropyl cellulose, hypromellose, red iron oxide, titanium dioxide and yellow iron oxide. figure1

Montelukast sodium tablets are a leukotriene receptor antagonist indicated for: • Prophylaxis and chronic treatment of asthma in patients 15 years of age and older (1.1). • Acute prevention of exercise-induced bronchoconstriction (EIB) in patients 15 years of age and older (1.2). • Relief of symptoms of allergic rhinitis (AR): seasonal allergic rhinitis (SAR) in patients 15 years of age and older, and perennial allergic rhinitis (PAR) in patients 15 years of age and older. Reserve use for patients who have an inadequate response or intolerance to alternative therapies (1.3). Limitations of Use: • Not indicated to treat an acute asthma attack ( 5.2 ). 1.1 Asthma Montelukast sodium tablets are indicated for the prophylaxis and chronic treatment of asthma in adults and adolescents 15 years of age and older. 1.2 Exercise-Induced Bronchoconstriction (EIB) Montelukast sodium tablets are indicated for prevention of exercise-induced bronchoconstriction (EIB) in patients 15 years of age and older. 1.3 Allergic Rhinitis Montelukast sodiumtablets are indicated for the relief of symptoms of seasonal allergic rhinitis in patients 15 years of age and older and perennial allergic rhinitis in patients 15 yearsof age and older. Because the benefits of montelukast sodium tablets may not outweigh the risk of neuropsychiatric symptoms in patients with allergic rhinitis [see Warnings and Precautions (5.1)], reserve use for patients who have an inadequate response or intolerance to alternative therapies. 1.4 Limitations of Use Montelukastsodium tablets are not indicated for the treatment of an acute asthma attack.

Administration (by indications): • Asthma: Once daily in the evening for patients 15 years and older.( 2.1 ). • Acute prevention of EIB: One tablet at least 2 hours before exercise for patients 15 years of age and older. ( 2.2 ) • Seasonal allergic rhinitis: Once daily for patients 15 years and older ( 2.3 ) • Perennial allergic rhinitis: Once daily for patients 15 years and older ( 2.3 ) Dosage (by age) • 15 years and older: one 10 mg tablet.( 2 ). Patients with both asthma and allergic rhinitis should take only one dose daily in the evening (2.4). 2.1 Asthma Forasthma, administer montelukast sodium tablets orally once daily in the evening, with or without food. There have been no clinical trials in patients with asthma toevaluate the relative efficacy of morning versus evening dosing. The following doses arerecommended: Table 1: RecommendedDosage in Asthma Age Dose Adult and adolescent patients 15 years of age and older one 10 mg tablet Patientswho miss a dose should take the next dose at their regular time and should not take 2 doses at the same time. 2.2 Exercise-Induced Bronchoconstriction (EIB) Forprevention�of EIB, administer a single dose of montelukast sodium tablets orally at least 2 hours, before exercise. The following doses arerecommended: Table 2: RecommendedDosage in Exercise-Induced Bronchoconstriction (EIB) Dose Adult and adolescent patients 15 years of age and older one 10 mg tablet An additional dose of montelukast sodium tablets should not be taken within 24 hours of a previous dose. Patients already taking montelukast sodium tablets daily for another indication (including chronic asthma) should not take an additional dose to prevent EIB. All patients should have available for rescue a short-acting β-agonist. Daily administration of montelukast sodium tablets for the chronic treatment of asthma has not been established to prevent acute episodes of EIB. 2.3 Allergic Rhinitis For allergic rhinitis, administer montelukast sodium tablets orally once daily without regard to time of food ingestion. Time of administration in patients with allergic rhinitis can be individualized to suit patient needs. The following doses for the treatment of symptoms ofseasonal allergic rhinitis are recommended: Table 3: RecommendedDosage in Seasonal Allergic Rhinitis Age Dose Adult and adolescent patients 15 years of age and older one 10 mg tablet The following doses for the treatment of symptoms of perennial allergic rhinitisare recommended: Table 4: Recommended Dosage in Perennial AllergicRhinitis Age Dose Adult and adolescent patients 15 years of age and older one 10 mg tablet Patients who miss a dose should take the next dose at their regular timeand should not take 2 doses at the same time. 2.4 Asthma and Allergic Rhinitis For patients with both asthma and allergic rhinitis, administer only one montelukast sodium tablets dose orally once daily in the evening. Patients who miss a dose should take the next dose at their regular time and should not take 2 doses at the same time.

Montelukast sodium tablets are contraindicated in patients with hypersensitivity to any of its components. • Hypersensitivity to any component of montelukast sodium tablets (4).

The following clinically significant adverse reactions are described elsewhere in the labeling: • Neuropsychiatric Events [see Warnings and Precautions ( 5.1 )] Most common adverse reactions (incidence ≥5% and greater than placebo listed in descending order of frequency): upper respiratory infection, fever, headache, pharyngitis, cough, abdominal pain, diarrhea, otitis media, influenza, rhinorrhea, sinusitis, otitis (6.1). To report SUSPECTED ADVERSE REACTIONS, contact Hetero Labs Limited at 1-866-495-1995 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 clinical practice. In the following description of clinical trials experience, adverse reactions are listed regardless of causality assessment. The most common adverse reactions (incidence ≥5% and greater than placebo; listed in descending order of frequency) in controlled clinical trials were: upper respiratory infection, fever, headache, pharyngitis, cough, abdominal pain, diarrhea, otitis media, influenza, rhinorrhea, sinusitis, otitis. Adults and Adolescents 15 Years of Age and Older with Asthma Montelukast sodium has been evaluated for safety in approximately 2950 adult and adolescent patients 15 years of age and older in clinical trials. In placebo-controlled clinical trials, the following adverse reactions reported with montelukast sodium occurred in greater than or equal to 1% of patients and at an incidence greater than that in patients treated with placebo: Table 5: Adverse Reactions Occurring in > 1% of Patients with an Incidence Greater than that in Patients Treated with Placebo Montelukast sodium 10 mg/day (%) (n=1955) Placebo (%) (n=1180) Body As A Whole Pain, abdominal Asthenia/fatigue Fever 2.9 1.8 1.5 2.5 1.2 0.9 Trauma Digestive System Disorders Dyspepsia 1.0 2.1 0.8 1.1 Pain, dental 1.7 1.0 Gastroenteritis, infectious 1.5 0.5 Nervous System/Psychiatric Headache 18.4 18.1 Dizziness 1.9 1.4 Respiratory System Disorders Influenza 4.2 3.9 Cough 2.7 2.4 Congestion, nasal 1.6 1.3 Skin/Skin Appendages Disorder Rash 1.6 1.2 Laboratory Adverse Reactions* ALT increased 2.1 2.0 AST increased 1.6 1.2 Pyuria 1.0 0.9 *Number of patients tested (montelukast sodium and placebo, respectively): ALT and AST, 1935, 1170; pyuria, 1924, 1159. The frequency of less common adverse reactions was comparable between montelukast sodium and placebo. The safety profile of montelukast sodium, when administered as a single dose for prevention of EIB in adult and adolescent patients 15 years of age and older, was consistent with the safety profile previously described for montelukast sodium. Cumulatively, 569 patients were treated with montelukast sodium for at least 6 months, 480 for one year, and 49 for two years in clinical trials. With prolonged treatment, the adverse reaction profile did not significantly change. Adults and Adolescents 15 Years of Age and Older with Seasonal Allergic Rhinitis Montelukast sodium has been evaluated for safety in 2199 adult and adolescent patients 15 years of age and older in clinical trials. Montelukast sodium administered once daily in the morning or in the evening had a safety profile similar to that of placebo. In placebo-controlled clinical trials, the following reaction was reported with montelukast sodium with a frequency ≥1% and at an incidence greater than placebo: upper respiratory infection, 1.9% of patients receiving montelukast sodium vs. 1.5% of patients receiving placebo. In a 4-week, placebo-controlled clinical study, the safety profile was consistent with that observed in 2-week studies. The incidence of somnolence was similar to that of placebo in all studies. Adults and Adolescents 15 Years of Age and Older with Perennial Allergic Rhinitis Montelukast sodium has been evaluated for safety in 3357 adult and adolescent patients 15 years of age and older with perennial allergic rhinitis of whom 1632 received montelukast sodium in two, 6-week, clinical studies. Montelukast sodium administered once daily had a safety profile consistent with that observed in patients with seasonal allergic rhinitis and similar to that of placebo. In these two studies, the following reactions were reported with montelukast sodium with a frequency ≥1% and at an incidence greater than placebo: sinusitis, upper respiratory infection, sinus headache, cough, epistaxis, and increased ALT. The incidence of somnolence was similar to that of placebo. 6.2 Postmarketing Experience The following adverse reactions have been identified during post-approval use of montelukast sodium. 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. Blood and lymphatic system disorders increased bleeding tendency, thrombocytopenia Immune system disorders hypersensitivity reactions including anaphylaxis, hepatic eosinophilic infiltration. Psychiatric disorders including, but not limited to, agitation, aggressive behavior or hostility, anxiousness, depression, disorientation, disturbance in attention, dream abnormalities, dysphemia (stuttering), hallucinations, insomnia, irritability, memory impairment, obsessive-compulsive symptoms, restlessness, somnambulism, suicidal thinking and behavior (including suicide), tic, and tremor [see Boxed Warning, Warnings and Precautions ( 5.1 )] Nervous system disorders drowsiness, paraesthesia/hypoesthesia, seizures Cardiac disorders palpitations Respiratory, thoracic and mediastinal disorders epistaxis, pulmonary eosinophilia Gastrointestinal disorders diarrhea, dyspepsia, nausea, pancreatitis, vomiting Hepatobiliary disorders Cases of cholestatic hepatitis, hepatocellular liver-injury, and mixed-pattern liver injury have been reported in patients treated with montelukast sodium. Most of these occurred in combination with other confounding factors, such as use of other medications, or when montelukast sodium was administered to patients who had underlying potential for liver disease such as alcohol use or other forms of hepatitis. Skin and subcutaneous tissue disorders angioedema, bruising, erythema multiforme, erythema nodosum, pruritus, Stevens-Johnson syndrome/toxic epidermal necrolysis, urticaria Musculoskeletal and connective tissue disorders arthralgia, myalgia including muscle cramps Renal and urinary disorders : enuresis in children General disorders and administration site conditions edema Patients with asthma on therapy with montelukast sodium may present with systemic eosinophilia, sometimes presenting with clinical features of vasculitis consistent with Churg-Strauss syndrome, a condition which is often treated with systemic corticosteroid therapy. These reactions have been sometimes associated with the reduction of oral corticosteroid therapy. Physicians should be alert to eosinophilia, vasculitic rash, worsening pulmonary symptoms, cardiac complications, and/or neuropathy presenting in their patients [see Warnings and Precautions (5.5)].

No dose adjustment is needed when montelukast sodium is co-administered with theophylline, prednisone, prednisolone, oral contraceptives, fexofenadine, digoxin, warfarin, gemfibrozil, itraconazole, thyroid hormones, sedative hypnotics, non-steroidal anti-inflammatory agents, benzodiazepines, decongestants, and Cytochrome P450 (CYP) enzyme inducers [see Clinical Pharmacology (12.3)].