FELODIPINE

Felodipine is a calcium antagonist (calcium channel blocker). Felodipine is a dihydropyridine derivative that is chemically described as ± ethyl methyl 4-(2, 3-dichlorophenyl)-1, 4-dihydro-2, 6-dimethyl-3, 5-pyridinedicarboxylate. Its empirical formula is C 18 H 19 Cl 2 NO 4 and its structural formula is: Felodipine, USP is a light yellow to yellow, crystalline powder with molecular weight of 384.26. It is insoluble in water and is freely soluble in acetone and in methanol; very slightly soluble in heptane. Felodipine is a racemic mixture. Felodipine extended-release tablets, USP provide extended release of felodipine. They are available as tablets containing 2.5 mg, 5 mg or 10 mg of felodipine, USP for oral administration. Inactive ingredients are: polyoxyl 40 hydrogenated castor oil, magnesium aluminum silicate, hypromellose 2208, lactose monohydrate, hydroxypropyl cellulose, sodium stearyl fumarate, hypromellose 2910 5cP, titanium dioxide and PEG 400. The 2.5 mg tablet strength also contains Iron oxide yellow, D&C yellow #10 aluminum lake and the 5 mg tablet strength also contains Iron oxide yellow. USP dissolution test pending. Image

Felodipine extended-release tablets, USP are indicated for the treatment of hypertension, to lower blood pressure. Lowering blood pressure lowers the risk of fatal and non-fatal cardiovascular events, primarily strokes and myocardial infarctions. These benefits have been seen in controlled trials of antihypertensive drugs from a wide variety of pharmacologic classes including felodipine. Control of high blood pressure should be part of comprehensive cardiovascular risk management, including, as appropriate, lipid control, diabetes management, antithrombotic therapy, smoking cessation, exercise, and limited sodium intake. Many patients will require more than 1 drug to achieve blood pressure goals. For specific advice on goals and management, see published guidelines, such as those of the National High Blood Pressure Education Program's Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC). Numerous antihypertensive drugs, from a variety of pharmacologic classes and with different mechanisms of action, have been shown in randomized controlled trials to reduce cardiovascular morbidity and mortality, and it can be concluded that it is blood pressure reduction, and not some other pharmacologic property of the drugs, that is largely responsible for those benefits. The largest and most consistent cardiovascular outcome benefit has been a reduction in the risk of stroke, but reductions in myocardial infarction and cardiovascular mortality also have been seen regularly. Elevated systolic or diastolic pressure causes increased cardiovascular risk, and the absolute risk increase per mmHg is greater at higher blood pressures, so that even modest reductions of severe hypertension can provide substantial benefit. Relative risk reduction from blood pressure reduction is similar across populations with varying absolute risk, so the absolute benefit is greater in patients who are at higher risk independent of their hypertension (for example, patients with diabetes or hyperlipidemia), and such patients would be expected to benefit from more aggressive treatment to a lower blood pressure goal. Some antihypertensive drugs have smaller blood pressure effects (as monotherapy) in black patients, and many antihypertensive drugs have additional approved indications and effects (eg, on angina, heart failure, or diabetic kidney disease). These considerations may guide selection of therapy. Felodipine extended-release tablets, USP may be administered with other antihypertensive agents.

The recommended starting dose is 5 mg once a day. Depending on the patient's response, the dosage can be decreased to 2.5 mg or increased to 10 mg once a day. These adjustments should occur generally at intervals of not less than 2 weeks. The recommended dosage range is 2.5-10 mg once daily. In clinical trials, doses above 10 mg daily showed an increased blood pressure response but a large increase in the rate of peripheral edema and other vasodilatory adverse events (see ADVERSE REACTIONS ). Modification of the recommended dosage is usually not required in patients with renal impairment. Felodipine extended-release tablets should regularly be taken either without food or with a light meal (see CLINICAL PHARMACOLOGY, Pharmacokinetics and Metabolism ). Felodipine extended-release tablets should be swallowed whole and not crushed or chewed. Geriatric Use - Patients over 65 years of age are likely to develop higher plasma concentrations of felodipine (see CLINICAL PHARMACOLOGY ). In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range (2.5 mg daily). Elderly patients should have their blood pressure closely monitored during any dosage adjustment. Patients with Impaired Liver Function - Patients with impaired liver function may have elevated plasma concentrations of felodipine and may respond to lower doses of felodipine extended-release tablets; therefore, patients should have their blood pressure monitored closely during dosage adjustment of felodipine extended-release tablets (see CLINICAL PHARMACOLOGY ).

Felodipine extended-release tablets are contraindicated in patients who are hypersensitive to this product.

In controlled studies in the United States and overseas, approximately 3000 patients were treated with felodipine as either the extended-release or the immediate-release formulation. The most common clinical adverse events reported with felodipine extended-release administered as monotherapy at the recommended dosage range of 2.5 mg to 10 mg once a day were peripheral edema and headache. Peripheral edema was generally mild, but it was age and dose related and resulted in discontinuation of therapy in about 3% of the enrolled patients. Discontinuation of therapy due to any clinical adverse event occurred in about 6% of the patients receiving felodipine extended-release tablets, principally for peripheral edema, headache, or flushing. Adverse events that occurred with an incidence of 1.5% or greater at any of the recommended doses of 2.5 mg to 10 mg once a day (felodipine extended-release tablets, N = 861; Placebo, N = 334), without regard to causality, are compared to placebo and are listed by dose in the table below. These events are reported from controlled clinical trials with patients who were randomized to a fixed dose of felodipine extended-release tablets or titrated from an initial dose of 2.5 mg or 5 mg once a day. A dose of 20 mg once a day has been evaluated in some clinical studies. Although the antihypertensive effect of felodipine extended-release tablets is increased at 20 mg once a day, there is a disproportionate increase in adverse events, especially those associated with vasodilatory effects (see DOSAGE AND ADMINISTRATION ). Percent of Patients with Adverse Events in Controlled Trials* of Felodipine Extended-Release Tablets (N = 861) as Monotherapy without Regard to Causality (Incidence of discontinuations shown in parentheses) Body System Adverse Events Placebo N=334 2.5 mg N=255 5 mg N=581 10 mg N= 408 Body as a whole Peripheral Edema 3.3 (0.0) 2.0 (0.0) 8.8 (2.2) 17.4 (2.5) Asthenia 3.3 (0.0) 3.9 (0.0) 3.3 (0.0) 2.2 (0.0) Warm Sensation 0.0 (0.0) 0.0 (0.0) 0.9 (0.2) 1.5 (0.0) Cardiovascular Palpitation 2.4 (0.0) 0.4 (0.0) 1.4 (0.3) 2.5 (0.5) Digestive Nausea 1.5 (0.9) 1.2 (0.0) 1.7 (0.3) 1.0 (0.7) Dyspepsia 1.2 (0.0) 3.9 (0.0) 0.7 (0.0) 0.5 (0.0) Constipation 0.9 (0.0) 1.2 (0.0) 0.3 (0.0) 1.5 (0.2) Nervous Headache 10.2 (0.9) 10.6 (0.4) 11.0 (1.7) 14.7 (2.0) Dizziness 2.7 (0.3) 2.7 (0.0) 3.6 (0.5) 3.7 (0.5) Paresthesia 1.5 (0.3) 1.6 (0.0) 1.2 (0.0) 1.2 (0.2) Respiratory Upper Respiratory Infection 1.8 (0.0) 3.9 (0.0) 1.9 (0.0) 0.7 (0.0) Cough 0.3 (0.0) 0.8 (0.0) 1.2 (0.0) 1.7 (0.0) Rhinorrhea 0.0 (0.0) 1.6 (0.0) 0.2 (0.0) 0.2 (0.0) Sneezing 0.0 (0.0) 1.6 (0.0) 0.0 (0.0) 0.0 (0.0) Skin Rash 0.9 (0.0) 2.0 (0.0) 0.2 (0.0) 0.2 (0.0) Flushing 0.9 (0.3) 3.9 (0.0) 5.3 (0.7) 6.9 (1.2) *Patients in titration studies may have been exposed to more than one dose level of felodipine extended-release tablets. Adverse events that occurred in 0.5 up to 1.5% of patients who received felodipine extended-release tablets in all controlled clinical trials at the recommended dosage range of 2.5 mg to 10 mg once a day, and serious adverse events that occurred at a lower rate, or events reported during marketing experience (those lower rate events are in italics) are listed below. These events are listed in order of decreasing severity within each category, and the relationship of these events to administration of felodipine extended-release tablets are uncertain: Body as a Whole : Chest pain, facial edema, flu-like illness Cardiovascular : Myocardial infarction, hypotension, syncope, angina pectoris , arrhythmia , tachycardia, premature beats Digestive: Abdominal pain, diarrhea, vomiting, dry mouth, flatulence, acid regurgitation Endocrine: Gynecomastia Hematologic: Anemia Metabolic : ALT (SGPT) increased Musculoskeletal: Arthralgia, back pain, leg pain, foot pain, muscle cramps, myalgia, arm pain, knee pain, hip pain Nervous/Psychiatric : Insomnia, depression, anxiety disorders, irritability, nervousness, somnolence, decreased libido Respiratory : Dyspnea, pharyngitis, bronchitis, influenza, sinusitis, epistaxis, respiratory infection Skin : Angioedema, contusion, erythema, urticaria , leukocytoclastic vasculitis Special Senses : Visual disturbances Urogenital : Impotence, urinary frequency, urinary urgency, dysuria, polyuria. Gingival Hyperplasia : Gingival hyperplasia, usually mild, occurred in < 0.5% of patients in controlled studies. This condition may be avoided or may regress with improved dental hygiene. (See PRECAUTIONS, Information for Patients .) Clinical Laboratory Test Findings Serum Electrolytes - No significant effects on serum electrolytes were observed during short- and long-term therapy (see CLINICAL PHARMACOLOGY:Renal/Endocrine Effects ). Serum Glucose - No significant effects on fasting serum glucose were observed in patients treated with felodipine extended-release tablets in the U.S. controlled study. Liver Enzymes - 1 of 2 episodes of elevated serum transaminases decreased once drug was discontinued in clinical studies; no follow-up was available for the other patient. To report SUSPECTED ADVERSE REACTIONS, contact Avet Pharmaceuticals Inc. at 1-866-901-DRUG (3784) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.