Oxybutynin Chloride

1 INDICATIONS AND USAGE Oxybutynin chloride extended-release tablets are muscarinic antagonist indicated for the treatment of overactive bladder with symptoms of urge urinary incontinence, urgency, and frequency. Oxybutynin chloride extended-release tablets are also indicated for the treatment of pediatric patients aged 6 years and older with symptoms of detrusor overactivity associated with a neurological condition (e.g., spina bifida). • Oxybutynin chloride extended-release tablets are a muscarinic antagonist indicated for the treatment of overactive bladder with symptoms of urge urinary incontinence, urgency, and frequency. ( Error! Hyperlink reference not valid. ) • Oxybutynin chloride extended-release tablets are also indicated for the treatment of pediatric patients aged 6 years and older with symptoms of detrusor overactivity associated with a neurological condition (e.g., spina bifida). ( Error! Hyperlink reference not valid. )

2 DOSAGE AND ADMINISTRATION Oxybutynin chloride extended-release tablets must be swallowed whole with the aid of liquids, and must not be chewed, divided, or crushed. Oxybutynin chloride extended-release tablets may be administered with or without food. Oxybutynin chloride extended-release tablets must be swallowed whole with the aid of liquids, and must not be chewed, divided, or crushed. Oxybutynin chloride extended-release tablets may be administered with or without food. ( Error! Hyperlink reference not valid. ) • Adults: Start with 5 mg or 10 mg, once daily at approximately the same time every day. Dose should not exceed 30 mg per day. ( 2.1 ) • Pediatric patients (6 years of age or older): Start with 5 mg, once daily at approximately the same time every day. Dose should not exceed 20 mg per day. ( 2.2 ) 2.1 Adults The recommended starting dose of Oxybutynin chloride extended-release tablet is 5 or 10 mg once daily at approximately the same time each day. Dosage may be adjusted in 5-mg increments to achieve a balance of efficacy and tolerability (up to a maximum of 30 mg/day). In general, dosage adjustment may proceed at approximately weekly intervals. 2.2 Pediatric Patients Aged 6 Years of Age and Older The recommended starting dose of oxybutynin chloride extended-release tablet is 5 mg once daily at approximately the same time each day. Dosage may be adjusted in 5-mg increments to achieve a balance of efficacy and tolerability (up to a maximum of 20 mg/day).

3 DOSAGE FORMS AND STRENGTHS Oxybutynin chloride extended-release tablets, USP are available as 5, 10 and 15 mg tablets for oral use: 5 mg: Pale yellow colored, round shaped, biconvex coated tablets imprinted with "EM1" on one side and plain on other side. 10 mg: Pink colored, round shaped, biconvex coated tablets imprinted with "EM2" on one side and plain on other side. 15 mg: Grey colored, round shaped, biconvex coated tablets imprinted with "EM3" on one side and plain on other side. Extended release tablets 5 mg, 10 mg and 15 mg ( Error! Hyperlink reference not valid. )

4 CONTRAINDICATIONS Oxybutynin chloride extended-release tablets are contraindicated in patients with urinary retention, gastric retention and other severe decreased gastrointestinal motility conditions, uncontrolled narrow-angle glaucoma. Oxybutynin chloride extended-release tablets are also contraindicated in patients who have demonstrated hypersensitivity to the drug substance or other components of the product. There have been reports of hypersensitivity reactions, including anaphylaxis and angiodema. • Urinary retention ( Error! Hyperlink reference not valid. ) • Gastric Retention ( Error! Hyperlink reference not valid. ) • Uncontrolled narrow angle glaucoma ( Error! Hyperlink reference not valid. ) • Known hypersensitivity to oxybutynin chloride extended-release tablets, oxybutynin or any component of oxybutynin chloride extended-release tablets ( Error! Hyperlink reference not valid. )

6 ADVERSE REACTIONS The most common (incidence greater than or equal to 5%) adverse reactions were dry mouth, constipation, diarrhea, headache, somnolence, and dizziness. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Ajanta Pharma USA Inc. at 1-855-664-7744 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, the 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. The safety and efficacy of oxybutynin chloride extended-release tablets (5 mg/day to 30 mg/day) was evaluated in 774 adult subjects who participated in five double-blind, controlled clinical trials. In four of the five studies, oxybutynin chloride tablets (5 mg/day to 20 mg/day in 199 subjects) was an active comparator. Adverse reactions reported by greater than or equal to 1% of subjects are shown in Table 1. Table 1: Adverse Drug Reactions Reported by greater than or equal to 1% of Oxybutynin Chloride Extended-Release Tablets - treated Adult Subjects in Five Double-blind, Controlled Clinical Trials of Oxybutynin Chloride Extended-Release Tablets . System/Organ Class Preferred Term Oxybutynin Chloride Extended-Release Tablets 5 to 30 mg/day n=774 % Oxybutynin Chloride Tablets 1 5 to 20 mg/day n=199 % Psychiatric Disorders Insomnia 3.0 5.5 Nervous System Disorders Headache 7.5 8.0 Somnolence 5.6 14.1 Dizziness 5.0 16.6 Dysgeusia 1.6 1.5 Eye Disorders Vision blurred 4.3 9.6 Dry eye 3.1 2.5 Respiratory, Thoracic and Mediastinal Disorders Cough 1.9 3.0 Oropharyngeal pain 1.9 1.5 Dry throat 1.7 2.5 Nasal dryness 1.7 4.5 Gastrointestinal Disorders Dry mouth 34.9 72.4 Constipation 8.7 15.1 Diarrhea 7.9 6.5 Dyspepsia 4.5 6.0 Nausea 4.5 11.6 Abdominal pain 1.6 2.0 Vomiting 1.3 1.5 Flatulence 1.2 2.5 Gastro-esophageal reflux disease 1.0 0.5 Skin and Subcutaneous Tissue Disorders Dry skin 1.8 2.5 Pruritus 1.3 1.5 Renal and Urinary Disorders Dysuria 1.9 2.0 Urinary hesitation 1.9 8.5 Urinary retention 1.2 3.0 General Disorders and Administration Site Conditions Fatigue 2.6 3.0 Investigations Residual urine volume 2 2.3 3.5 1 Immediate-release formulation 2 The bundled term residual urine volume consists of the preferred terms residual urine volume and residual urine volume increased. The discontinuation rate due to adverse reactions was 4.4% with oxybutynin chloride extended-release tablets compared to 0% with oxybutynin chloride tablets. The most frequent adverse reaction causing discontinuation of study medication was dry mouth (0.7%). The following adverse reactions were reported by less than 1% of oxybutynin chloride extended-release tablets-treated patients and at a higher incidence than placebo in clinical trials: Metabolism and Nutrition Disorders: anorexia, fluid retention; Vascular disorders: hot flush; Respiratory, thoracic and mediastinal disorders: dysphonia; Gastrointestinal Disorders: dysphagia, frequent bowel movements; General disorders and administration site conditions: chest discomfort, thirst. 6.2 Postmarketing Experience The following additional adverse reactions have been reported from worldwide postmarketing experience with oxybutynin chloride extended-release tablets. Because postmarketing 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. Infections and Infestations: Urinary tract infection; Psychiatric Disorders: psychotic disorder, agitation, confusional state, hallucinations, memory impairment, abnormal behavior; Nervous System Disorders: convulsions; Eye Disorders: glaucoma; Respiratory, Thoracic and Mediastinal Disorders: nasal congestion; Cardiac Disorders: arrhythmia, tachycardia, palpitations; QT interval prolongation; Vascular Disorders: flushing, hypertensi …

7 DRUG INTERACTIONS The concomitant use of oxybutynin with other anticholinergic drugs or with other agents which produce dry mouth, constipation, somnolence (drowsiness), and/or other anticholinergic-like effects may increase the frequency and/or severity of such effects. Anticholinergic agents may potentially alter the absorption of some concomitantly administered drugs due to anticholinergic effects on gastrointestinal motility. This may be of concern for drugs with a narrow therapeutic index. Anticholinergic agents may also antagonize the effects of prokinetic agents, such as metoclopramide. Mean oxybutynin chloride plasma concentrations were approximately 2 fold higher when oxybutynin chloride extended-release tablet was administered with ketoconazole, a potent CYP3A4 inhibitor. Other inhibitors of the cytochrome P450 3A4 enzyme system, such as antimycotic agents (e.g., itraconazole and miconazole) or macrolide antibiotics (e.g., erythromycin and clarithromycin), may alter oxybutynin mean pharmacokinetic parameters (i.e., C max and AUC). The clinical relevance of such potential interactions is not known. Caution should be used when such drugs are co-administered. • Co-administration with other anticholinergic drugs may increase the frequency and/or severity of anticholinergic-like effects. ( Error! Hyperlink reference not valid. ) • Co-administration with strong cytochrome P450 (CYP) 3A4 inhibitors (e.g., ketoconazole) increases the systemic exposure of oxybutynin. ( Error! Hyperlink reference not valid. )

8 USE IN SPECIFIC POPULATIONS • Pediatric Use: Oxybutynin chloride extended-release tablets are not recommended in pediatric patients who cannot swallow the tablet whole without chewing, dividing or crushing, or in children under the age of 6 years. ( 8.4 ) • Renal or Hepatic Impairment: There have been no studies conducted in patients with renal or hepatic impairment. ( 8.6 , 8.7 ) 8.1 Pregnancy Risk Summary There are no adequate data on oxybutynin chloride extended-release tablets use in pregnant women to evaluate for a drug-associated risk of major birth defects, miscarriage or adverse maternal or fetal outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively. The background risk of major birth defects and miscarriage for the indicated population is unknown. 8.2 Lactation Risk Summary There are no data on the presence of oxybutynin in human milk, the effects on the breastfed infant, or the effects of oxybutynin chloride extended-release tablets on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for oxybutynin chloride extended-release tablets and any potential adverse effects on the breastfed child from oxybutynin chloride extended-release tablets or from the underlying maternal condition. 8.4 Pediatric Use The safety and efficacy of oxybutynin chloride extended-release tablets were studied in 60 children in a 24-week, open-label, non-randomized trial. Patients were aged 6-15 years, all had symptoms of detrusor overactivity in association with a neurological condition (e.g., spina bifida), all used clean intermittent catheterization, and all were current users of oxybutynin chloride. Study results demonstrated that administration of oxybutynin chloride extended-release tablets 5 to 20 mg/day was associated with an increase from baseline in mean urine volume per catheterization from 108 mL to 136 mL, an increase from baseline in mean urine volume after morning awakening from 148 mL to 189 mL, and an increase from baseline in the mean percentage of catheterizations without a leaking episode from 34% to 51%. Urodynamic results were consistent with clinical results. Administration of oxybutynin chloride extended-release tablets resulted in an increase from baseline in mean maximum cystometric capacity from 185 mL to 254 mL, a decrease from baseline in mean detrusor pressure at maximum cystometric capacity from 44 cm H 2 O to 33 cm H 2 O, and a reduction in the percentage of patients demonstrating uninhibited detrusor contractions (of at least 15 cm H 2 O) from 60% to 28%. The pharmacokinetics of oxybutynin chloride extended-release tablets in these patients were consistent with those reported for adults [see Clinical Pharmacology (12.3) ] . Oxybutynin chloride extended-release tablets are not recommended in pediatric patients who cannot swallow the tablet whole without chewing, dividing, or crushing, or in children under the age of 6. 8.5 Geriatric Use The rate and severity of anticholinergic effects reported by patients less than 65 years old and those 65 years and older were similar. The pharmacokinetics of oxybutynin chloride extended-release tablets were similar in all patients studied (up to 78 years of age). 8.6 Renal Impairment There were no studies conducted with oxybutynin chloride extended-release tablets in patients with renal impairment. 8.7 Hepatic Impairment There were no studies conducted with oxybutynin chloride extended-release tablets in patients with hepatic impairment.

Use in Specific Populations Pediatric The pharmacokinetics of oxybutynin chloride extended release tablets were evaluated in 19 children aged 5-15 years with detrusor overactivity associated with a neurological condition (e.g., spina bifida). The pharmacokinetics of oxybutynin chloride extended-release tablets in these pediatric patients w …

12.1 Mechanism of Action Oxybutynin relaxes bladder smooth muscle. Oxybutynin chloride exerts a direct antispasmodic effect on smooth muscle and inhibits the muscarinic action of acetylcholine on smooth muscle. No blocking effects occur at skeletal neuromuscular junctions or autonomic ganglia (antinicotinic effects). Antimuscarinic activity resides predominantly in the R-isomer. A metabolite, desethyloxybutynin, has pharmacological activity similar to that of oxybutynin in in vitro studies.

11 DESCRIPTION Oxybutynin chloride USP is an antispasmodic, muscarinic antagonist. Each oxybutynin chloride extended-release tablet USP contains 5 mg, 10 mg or 15 mg of oxybutynin chloride USP, formulated as a once-a-day controlled-release tablet for oral administration. Oxybutynin chloride is administered as a racemate of R- and S-enantiomers. Chemically, oxybutynin chloride is d,l (racemic) 4-diethylamino-2-butynylphenylcyclohexylglycolate hydrochloride. The empirical formula of oxybutynin chloride is C 22 H 31 NO 3 •HCl. Its structural formula is: Oxybutynin chloride USP is a white crystalline solid with a molecular weight of 393.9. It is readily soluble in water and acids, but relatively insoluble in alkalis. Oxybutynin chloride extended-release tablet, USP also contains the following inert ingredients: polyethylene oxide, hypromellose, sodium chloride, butylated hydroxytoluene, ferric oxide (yellow), ferric oxide (red), ferric oxide (black), colloidal silicon dioxide, magnesium stearate, cellulose acetate, polyethylene glycol, titanium dioxide, lactose monohydrate, triacetin, shellac, and propylene glycol. System Components and Performance Oxybutynin chloride extended-release tablets USP uses osmotic pressure to deliver oxybutynin chloride at a controlled rate over approximately 24 hours. The system, which resembles a conventional tablet in appearance, comprises an osmotically active bilayer core surrounded by a semipermeable membrane. The bilayer core is composed of a drug layer containing the drug and excipients, and a push layer containing osmotically active components. There is a precision-laser drilled orifice in the semipermeable membrane on the drug-layer side of the tablet. In an aqueous environment, such as the gastrointestinal tract, water permeates through the membrane into the tablet core, causing the drug to go into suspension and the push layer to expand. This expansion pushes the suspended drug out through the orifice. The semipermeable membrane controls the rate at which water permeates into the tablet core, which in turn controls the rate of drug delivery. The controlled rate of drug delivery into the gastrointestinal lumen is thus independent of pH or gastrointestinal motility. The function of oxybutynin chloride extended-release tablets depends on the existence of an osmotic gradient between the contents of the bilayer core and the fluid in the gastrointestinal tract. Since the osmotic gradient remains constant, drug delivery remains essentially constant. The biologically inert components of the tablet remain intact during gastrointestinal transit and are eliminated in the feces as an insoluble shell. Product meets USP Dissolution Test 6 structural-formula

10 OVERDOSAGE The continuous release of oxybutynin from Oxybutynin chloride extended-release tablets should be considered in the treatment of overdosage. Patients should be monitored for at least 24 hours. Treatment should be symptomatic and supportive. Activated charcoal as well as a cathartic may be administered. Overdosage with oxybutynin chloride has been associated with anticholinergic effects including central nervous system excitation, flushing, fever, dehydration, cardiac arrhythmia, vomiting, and urinary retention. Ingestion of 100 mg oxybutynin chloride in association with alcohol has been reported in a 13-year-old boy who experienced memory loss, and a 34-year-old woman who developed stupor, followed by disorientation and agitation on awakening, dilated pupils, dry skin, cardiac arrhythmia, and retention of urine. Both patients fully recovered with symptomatic treatment.

16 HOW SUPPLIED/STORAGE AND HANDLING Oxybutynin chloride extended-release tablets USP, 5 mg are supplied as purple, round, biconvex, coated tablets debossed with “A31” on one side and plain on the other side. They are available as follows: Bottles of 30: NDC 65162-371-03 Bottles of 90: NDC 65162-371-09 Bottles of 100: NDC 65162-371-10 Bottles of 500: NDC 65162-371-50 Oxybutynin chloride extended-release tablets USP, 10 mg are supplied as pink, round, biconvex, coated tablets debossed with “A32” on one side and plain on the other side. They are available as follows: Bottles of 30: NDC 65162-372-03 Bottles of 90: NDC 65162-372-09 Bottles of 100: NDC 65162-372-10 Bottles of 500: NDC 65162-372-50 Oxybutynin chloride extended-release tablets USP, 15 mg are supplied as white, round, biconvex, coated tablets debossed with “A33” on one side and plain on the other side. They are available as follows: Bottles of 30: NDC 65162-373-03 Bottles of 90: NDC 65162-373-09 Bottles of 100: NDC 65162-373-10 Bottles of 250: NDC 65162-373-25 Bottles of 500: NDC 65162-373-50 Store at 20° to 25°C (68° to 77°F); excursions permitted between 15° to 30°C (59° to 86°F) [see USP Controlled Room Temperature]. Protect from moisture and humidity. Keep out of the reach of children.