Metoprolol Succinate

5 WARNINGS AND PRECAUTIONS Abrupt cessation may exacerbate myocardial ischemia. ( 5 ) Heart Failure: Worsening cardiac failure may occur. ( 5.2 ) Bronchospastic Disease: Avoid beta blockers. ( 5.3 ) Concomitant use of glycosides, clonidine, and diltiazem and verapamil with beta-blockers can increase the risk of bradycardia. ( 5.4 ) Pheochromocytoma: Initiate therapy with an alpha blocker. ( 5.5 ) Major Surgery: Avoid initiation of high-dose extended-release metoprolol in patients undergoing non-cardiac surgery. Do not routinely withdraw chronic beta blocker therapy prior to surgery.( 5.6 , 6.1 ) Diabetes and Hypoglycemia: May mask tachycardia occurring with hypoglycemia.( 5.7 ) Thyrotoxicosis: Abrupt withdrawal in patients with thyrotoxicosis might precipitate a thyroid storm.( 5.8 ) Peripheral Vascular Disease: Can aggravate symptoms of arterial insufficiency.( 5.9 ) Patients may be unresponsive to the usual doses of epinephrine used to treat allergic reaction. ( 5.10 ) 5.1 Abrupt Cessation of Therapy Following abrupt cessation of therapy with certain beta-blocking agents, exacerbations of angina pectoris and, in some cases, myocardial infarction have occurred. When discontinuing chronically administered metoprolol succinate extended-release tablets, particularly in patients with ischemic heart disease, gradually reduce the dosage over a period of 1 to 2 weeks and monitor the patient. If angina markedly worsens or acute coronary ischemia develops, promptly reinstate metoprolol succinate extended-release tablets, and take measures appropriate for the management of unstable angina. Warn patients not to interrupt therapy without their physician’s advice. Because coronary artery disease is common and may be unrecognized, avoid abruptly discontinuing metoprolol succinate extended-release tablets in patients treated only for hypertension. 5.2 Heart Failure Worsening cardiac failure may occur during up-titration of metoprolol succinate extended-release tablets. If such symptoms occur, increase diuretics and restore clinical stability before advancing the dose of metoprolol succinate extended-release tablets [ see Dosage and Administration (2) ] . It may be necessary to lower the dose of metoprolol succinate extended-release tablets or temporarily discontinue it. Such episodes do not preclude subsequent successful titration of metoprolol succinate extended-release tablets. 5.3 Bronchospastic Disease Patients with bronchospastic diseases should, in general, not receive beta-blockers. Because of its relative beta1 cardio- selectivity, however, metoprolol succinate extended-release tablets may be used in patients with bronchospastic disease who do not respond to, or cannot tolerate, other antihypertensive treatment. Because beta1-selectivity is not absolute, use the lowest possible dose of metoprolol succinate extended-release tablets. Bronchodilators, including beta2-agonists, should be readily available or administered concomitantly [ see Dosage and Administration (2) ] . 5.4 Bradycardia Bradycardia, including sinus pause, heart block, and cardiac arrest have occurred with the use of metoprolol succinate extended-release tablets. Patients with first-degree atrioventricular block, sinus node dysfunction, conduction disorders (including Wolff- Parkinson-White) or on concomitant drugs that cause bradycardia [ see Drug Interactions (7.3) ], may be at increased risk. Monitor heart rate in patients receiving metoprolol succinate extended-release tablets. If severe bradycardia develops, reduce or stop metoprolol succinate extended-release tablets. 5.5 Pheochromocytoma If metoprolol succinate extended-release tablets are used in the setting of pheochromocytoma, it should be given in combination with an alpha blocker, and only after the alpha blocker has been initiated. Administration of beta-blockers alone in the setting of pheochromocytoma has been associated with a paradoxical increase in blood pressure due to the attenuation of beta-mediated vasodilatation in skeletal muscle. 5.6 Major Surgery Avoid initiation of a high-dose regimen of extended-release metoprolol in patients undergoing non-cardiac surgery, since such use in patients with cardiovascular risk factors has been associated with bradycardia, hypotension, stroke and death. Chronically administered beta-blocking therapy should not be routinely withdrawn prior to major surgery, however, the impaired ability of the heart to respond to reflex adrenergic stimuli may augment the risks of general anesthesia and surgical procedures. 5.7 Hepatic Impairment Beta-blockers may mask tachycardia occurring with hypoglycemia, but other manifestations such as dizziness and sweating may not be significantly affected. 5.8 Thyrotoxicosis Beta-adrenergic blockade may mask certain clinical signs of hyperthyroidism, such as tachycardia. Abrupt withdrawal of beta-blockade may precipitate a thyroid storm. 5.9 Peripheral Vascular Disease Beta-blockers can precipitate or aggravate symptoms of arterial insufficiency in patients with peripheral vascular disease. 5.10 Anaphylactic Reaction While taking beta-blockers, patients with a history of severe anaphylactic reactions to a variety of allergens may be more reactive to repeated challenge and may be unresponsive to the usual doses of epinephrine used to treat an allergic reaction.

6 ADVERSE REACTIONS The following adverse reactions are described elsewhere in labeling: Worsening angina or myocardial infarction [ see Warnings and Precautions (5) ] Worsening heart failure [ see Warnings and Precautions (5) ] Worsening AV block [ see Contraindications (4) ] Most common adverse reactions: tiredness, dizziness, depression, shortness of breath, bradycardia, hypotension, diarrhea, pruritus, rash. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Oryza Pharmaceuticals, Inc. at 1-866-637-4281 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. The adverse reaction information from clinical trials does, however, provide a basis for identifying the adverse events that appear to be related to drug use and for approximating rates. Hypertension and Angina: Most adverse reactions have been mild and transient. The most common (>2%) adverse reactions are tiredness, dizziness, depression, diarrhea, shortness of breath, bradycardia, and rash. Heart Failure: In the MERIT-HF study comparing metoprolol succinate extended-release tablets in daily doses up to 200 mg (mean dose 159 mg once- daily; n=1990) to placebo (n=2001), 10.3% of metoprolol succinate extended-release tablets patients discontinued for adverse reactions vs. 12.2% of placebo patients. The table below lists adverse reactions in the MERIT-HF study that occurred at an incidence of ≥ 1% in the metoprolol succinate extended-release tablets group and greater than placebo by more than 0.5%, regardless of the assessment of causality. Adverse Reactions Occuring in the MERIT-HF Study at an Incidence ≥ 1% in the Metoprolol Succinate Extended-Release Tablets Group and Greater Than Placebo by More Than 0.5% Metoprolol succinateextended-release tablets n=1990 % of patients Placebo n=2001 % of patients Dizziness/vertigo 1.8 1.0 Bradycardia 1.5 0.4 Post-operative Adverse Events: In a randomized, double-blind, placebo-controlled trial of 8351 patients with or at risk for atherosclerotic disease undergoing non-vascular surgery and who were not taking beta–blocker therapy, metoprolol succinate extended-release tablets 100 mg was started 2 to 4 hours prior to surgery then continued for 30 days at 200 mg per day. Metoprolol succinate extended-release tablets use was associated with a higher incidence of bradycardia (6.6% vs. 2.4%; HR, 2.74; 95% CI 2.19, 3.43), hypotension (15% vs.9.7%; HR 1.55; 95% CI 1.37, 1.74), stroke (1.0% vs. 0.5%; HR 2.17; 95% CI 1.26, 3.74) and death (3.1% vs. 2.3%; HR 1.33; 95% CI 1.03, 1.74) compared to placebo. 6.2 Post-Marketing Experience The following adverse reactions have been identified during post-approval use of metoprolol succinate extended-release tablets or immediate-release metoprolol. 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. Cardiovascular: Cold extremities, arterial insufficiency (usually of the Raynaud type), palpitations, peripheral edema, syncope, chest pain and hypotension. Respiratory: Wheezing (bronchospasm), dyspnea. Central Nervous System: Confusion, short-term memory loss, headache, somnolence, nightmares, insomnia, anxiety/nervousness, hallucinations, paresthesia. Gastrointestinal: Nausea, dry mouth, constipation, flatulence, heartburn, hepatitis, vomiting. Hypersensitive Reactions: Pruritus. Miscellaneous: Musculoskeletal pain, arthralgia, blurred vision, decreased libido, male impotence, tinnitus, reversible alopecia, agranulocytosis, dry eyes, worsening of psoriasis, Peyronie’s disease, sweating, photosensitivity, taste disturbance. Potential Adverse Reactions: In addition, there are adverse reactions not listed above that have been reported with other beta-adrenergic blocking agents and should be considered potential adverse reactions to metoprolol succinate extended-release tablets. Central Nervous System: Reversible mental depression progressing to catatonia; an acute reversible syndrome characterized by disorientation for time and place, short-term memory loss, emotional lability, clouded sensorium, and decreased performance on neuropsychometrics. Hematologic: Agranulocytosis, nonthrombocytopenic purpura, thrombocytopenic purpura. Hypersensitive Reactions: Laryngospasm, respiratory distress.

<table width="614px"><caption>Adverse Reactions Occuring in the MERIT-HF Study at an Incidence &#x2265; 1% in the Metoprolol Succinate Extended-Release Tablets Group and Greater Than Placebo by More Than 0.5%</caption><thead><tr styleCode="First Last"><td align="left" styleCode="BotruleLruleRruleToprule" valign="middle"/><td align="left" styleCode="BotruleLruleRruleToprule" valign="middle">Metoprolol succinateextended-release tablets n=1990 % of patients </td><td align="left" styleCode="BotruleLruleRruleToprule" valign="middle">Placebo n=2001 % of patients </td></tr></thead><tbody><tr><td align="left" styleCode="BotruleLruleRruleToprule" valign="middle">Dizziness/vertigo</td><td align="center" styleCode="BotruleLruleRruleToprule" valign="middle">1.8</td><td align="center" styleCode="BotruleLruleRruleToprule" valign="middle">1.0</td></tr><tr><td align="left" styleCode="BotruleLruleRruleToprule" valign="middle">Bradycardia</td><td align="center" styleCode="BotruleLruleRruleToprule" valign="middle">1.5</td><td align="center" styleCode="BotruleLruleRruleToprule" valign="middle">0.4</td></tr></tbody></table>