ACEBUTOLOL HYDROCHLORIDE

Acebutolol hydrochloride USP is a selective, hydrophilic beta-adrenoreceptor blocking agent with mild intrinsic sympathomimetic activity for use in treating patients with hypertension and ventricular arrhythmias. It is marketed in capsule form for oral administration. Acebutolol Hydrochloride Capsules USP are provided in two dosage strengths which contain 200 mg or 400 mg of acebutolol as the hydrochloride salt. The inactive ingredients are povidone, corn starch, pregelatinized starch, and stearic acid. The capsule shells and imprinting ink for the 200 mg dosage strength also contain FD&C Blue 1, FD&C Red 40, titanium dioxide, black iron oxide, yellow iron oxide, sodium lauryl sulfate, gelatin, carboxymethylcellulose, shellac, ammonium hydroxide, propylene glycol, and potassium hydroxide. The capsule shells and imprinting ink for the 400 mg dosage strength also contain FD&C Blue 1, FD&C Red 3, titanium dioxide, FD&C Yellow 6, D&C Yellow 10, sodium lauryl sulfate, gelatin, shellac, ammonium hydroxide, propylene glycol, simethicone, and sodium hydroxide. Acebutolol hydrochloride USP has the following structural formula: C 18 H 28 N 2 O 4 •HCl M.W. 372.9 Acebutolol hydrochloride USP is a white or slightly off-white powder freely soluble in water, and less soluble in alcohol. Chemically it is defined as the hydrochloride salt of (±)N-[3-Acetyl-4-[2-hydroxy-3-[(1-methylethyl)amino]propoxy]phenyl] butanamide. Structure

Hypertension Acebutolol Hydrochloride Capsules USP are indicated for the management of hypertension in adults. It may be used alone or in combination with other antihypertensive agents, especially thiazide-type diuretics. Ventricular Arrhythmias Acebutolol Hydrochloride Capsules USP are indicated in the management of ventricular premature beats; it reduces the total number of premature beats, as well as the number of paired and multiform ventricular ectopic beats, and R-on-T beats.

Hypertension The initial dosage of acebutolol in uncomplicated mild-to-moderate hypertension is 400 mg. This can be given as a single daily dose, but in occasional patients twice daily dosing may be required for adequate 24-hour blood-pressure control. An optimal response is usually achieved with dosages of 400 mg to 800 mg per day, although some patients have been maintained on as little as 200 mg per day. Patients with more severe hypertension or who have demonstrated inadequate control may respond to a total of 1200 mg daily (administered b.i.d.), or to the addition of a second antihypertensive agent. Beta-1 selectivity diminishes as dosage is increased. Ventricular Arrhythmia The usual initial dose of acebutolol is 400 mg daily given as 200 mg b.i.d. Dosage should be increased gradually until an optimal clinical response is obtained, generally at 600 mg to 1200 mg per day. If treatment is to be discontinued, the dosage should be reduced gradually over a period of about two weeks. Use in Older Patients Older patients have an approximately 2-fold increase in bioavailability and may require lower maintenance doses. Doses above 800 mg/day should be avoided in the elderly.

Acebutolol hydrochloride capsules are contraindicated in: 1) persistently severe bradycardia; 2) second- and third-degree heart block; 3) overt cardiac failure; and 4) cardiogenic shock. (See WARNINGS .)

Acebutolol is well tolerated in properly selected patients. Most adverse reactions have been mild, not required discontinuation of therapy, and tended to decrease as duration of treatment increases. The following table shows the frequency of treatment-related side effects derived from controlled clinical trials in patients with hypertension, angina pectoris, and arrhythmia. These patients received acebutolol, propranolol, or hydrochlorothiazide as monotherapy, or placebo. TOTAL VOLUNTEERED AND ELICITED (U.S. STUDIES) Body System/ Adverse Reaction Acebutolol (N=1002) % Propranolol (N=424) % Hydrochlorothiazide (N=178) % Placebo (N=314) % Cardiovascular Chest Pain 2 4 4 1 Edema 2 2 4 1 Central Nervous System Depression 2 1 3 1 Dizziness 6 7 12 2 Fatigue 11 17 10 4 Headache 6 9 13 4 Insomnia 3 6 5 1 Abnormal dreams 2 3 0 1 Dermatologic Rash 2 2 4 1 Gastrointestinal Constipation 4 2 7 0 Diarrhea 4 5 5 1 Dyspepsia 4 6 3 1 Flatulence 3 4 7 1 Nausea 4 6 3 0 Genitourinary Micturition (frequency) 3 1 9 <1 Musculoskeletal Arthralgia 2 1 3 2 Myalgia 2 1 4 0 Respiratory Cough 1 1 2 0 Dyspnea 4 6 4 2 Rhinitis 2 1 4 <1 Special Senses Abnormal Vision 2 2 3 0 The following selected (potentially important) side effects were seen in up to 2% of acebutolol patients: Cardiovascular: hypotension, bradycardia, heart failure. Central Nervous System: anxiety, hyper/hypoesthesia, impotence. Dermatological: pruritus. Gastrointestinal: vomiting, abdominal pain. Genitourinary: dysuria, nocturia. Liver and Biliary System: A small number of cases of liver abnormalities (increased SGOT, SGPT, LDH) have been reported in association with acebutolol therapy. In some cases increased bilirubin or alkaline phosphatase, fever, malaise, dark urine, anorexia, nausea, headache, and/or other symptoms have been reported. In some of the reported cases, the symptoms and signs were confirmed by rechallenge with acebutolol. The abnormalities were reversible upon cessation of acebutolol therapy. Musculoskeletal: back pain, joint pain. Respiratory: pharyngitis, wheezing. Special Senses: conjunctivitis, dry eye, eye pain. Autoimmune: In extremely rare instances, systemic lupus erythematosus has been reported. The incidence of drug-related adverse effects (volunteered and solicited) according to acebutolol dose is shown below. (Data from 266 hypertensive patients treated for 3 months on a constant dose.) Body System 400 mg/day (N=132) 800 mg/day (N=63) 1200 mg/day (N=71) Cardiovascular 5% 2% 1% Gastrointestinal 3% 3% 1% Musculoskeletal 2% 3% 4% Central Nervous System 9% 13% 17% Respiratory 1% 5% 6% Skin 1% 2% 1% Special Senses 2% 2% 6% Genitourinary 2% 3% 1% Potential Adverse Events In addition, certain adverse effects not listed above have been reported with other β-blocking agents and should also be considered as potential adverse effects of acebutolol. Central Nervous System: Reversible mental depression progressing to catatonia (an acute syndrome characterized by disorientation for time and place), short-term memory loss, emotional lability, slightly clouded sensorium, and decreased performance (neuropsychometrics). Cardiovascular: Intensification of AV block (see CONTRAINDICATIONS ). Allergic: Erythematous rash, fever combined with aching and sore throat, laryngospasm, and respiratory distress. Hematologic: Agranulocytosis, nonthrombocytopenic, and thrombocytopenic purpura. Gastrointestinal: Mesenteric arterial thrombosis and ischemic colitis. Miscellaneous: Reversible alopecia and Peyronie’s disease. The oculomucocutaneous syndrome associated with the β-blocker practolol has not been reported with acebutolol during investigational use and extensive foreign clinical experience. To report SUSPECTED ADVERSE REACTIONS, contact ANI Pharmaceuticals, Inc. at 1-855-204-1431 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

Catecholamine-depleting drugs, such as reserpine, may have an additive effect when given with β-blocking agents. Patients treated with acebutolol plus catecholamine depletors should, therefore, be observed closely for evidence of marked bradycardia or hypotension which may present as vertigo, syncope/presyncope, or orthostatic changes in blood pressure without compensatory tachycardia. Exaggerated hypertensive responses have been reported from the combined use of β-adrenergic antagonists and α-adrenergic stimulants, including those contained in proprietary cold remedies and vasoconstrictive nasal drops. Patients receiving β-blockers should be warned of this potential hazard. Blunting of the antihypertensive effect of beta-adrenoreceptor blocking agents by nonsteroidal anti-inflammatory drugs has been reported. No significant interactions with digoxin, hydrochlorothiazide, hydralazine, sulfinpyrazone, oral contraceptives, tolbutamide, or warfarin have been observed. Both digitalis glycosides and beta-blockers slow atrioventricular conduction and decrease heart rate. Concomitant use can increase the risk of bradycardia.