Irbesartan And Hydrochlorothiazide

1 INDICATIONS AND USAGE AVALIDE ® (irbesartan and hydrochlorothiazide) tablets are indicated for the treatment of hypertension. AVALIDE may be used in patients whose blood pressure is not adequately controlled on monotherapy. AVALIDE may also be used as initial therapy in patients who are likely to need multiple drugs to achieve their blood pressure goals. The choice of AVALIDE as initial therapy for hypertension should be based on an assessment of potential benefits and risks. Patients with stage 2 (moderate or severe) hypertension are at relatively high risk for cardiovascular events (such as strokes, heart attacks, and heart failure), kidney failure, and vision problems, so prompt treatment is clinically relevant. The decision to use a combination as initial therapy should be individualized and may be shaped by considerations such as the baseline blood pressure, the target goal, and the incremental likelihood of achieving goal with a combination compared with monotherapy. Data from Studies V and VI [see Clinical Studies (14.2) ] provide estimates of the probability of reaching a blood pressure goal with AVALIDE compared to irbesartan or hydrochlorothiazide (HCTZ) monotherapy. The relationship between baseline blood pressure and achievement of a SeSBP <140 or <130 mmHg or SeDBP <90 or <80 mmHg in patients treated with AVALIDE compared to patients treated with irbesartan or HCTZ monotherapy are shown in Figures 1a through 2b. Figure 1a: Probability of Achieving SBP <140 mmHg in Patients from Initial Therapy Studies V (Week 8) and VI (Week 7) For all probability curves, patients without blood pressure measurements at Week 7 (Study VI) and Week 8 (Study V) were counted as not reaching goal (intent-to-treat analysis). Figure 1b: Probability of Achieving SBP <130 mmHg in Patients from Initial Therapy Studies V (Week 8) and VI (Week 7) Figure 2a: Probability of Achieving DBP <90 mmHg in Patients from Initial Therapy Studies V (Week 8) and VI (Week 7) Figure 2b: Probability of Achieving DBP <80 mmHg in Patients from Initial Therapy Studies V (Week 8) and VI (Week 7) The above graphs provide a rough approximation of the likelihood of reaching a targeted blood pressure goal (e.g., Week 8 sitting systolic blood pressure ≤140 mmHg) for the treatment groups. The curve of each treatment group in each study was estimated by logistic regression modeling from all available data of that treatment group. The estimated likelihood at the right tail of each curve is less reliable due to small numbers of subjects with high baseline blood pressures. For example, a patient with a blood pressure of 180/105 mmHg has about a 25% likelihood of achieving a goal of <140 mmHg (systolic) and 50% likelihood of achieving <90 mmHg (diastolic) on irbesartan alone (and lower still likelihoods on HCTZ alone). The likelihood of achieving these goals on AVALIDE rises to about 40% (systolic) or 70% (diastolic). AVALIDE is a combination of irbesartan, an angiotensin II receptor antagonist, and hydrochlorothiazide, a thiazide diuretic, indicated for hypertension: In patients not adequately controlled with monotherapy. ( 1 ) As initial therapy in patients likely to need multiple drugs to achieve their blood pressure goals. ( 1 ) Figure 1a Figure 1b Figure 2a Figure 2b

2 DOSAGE AND ADMINISTRATION General Considerations Maximum effects within 2 to 4 weeks after dose change. ( 2.1 ) Renal impairment: Not recommended for patients with severe renal impairment (creatinine clearance <30 mL/min). ( 2.1 , 5.8 ) Hypertension Initiate with 150/12.5 mg. Titrate to 300/12.5 mg then 300/25 mg if needed. ( 2.2 ) Replacement therapy: May be substituted for titrated components. ( 2.3 ) 2.1 General Considerations The side effects of irbesartan are generally rare and apparently independent of dose; those of hydrochlorothiazide are a mixture of dose-dependent (primarily hypokalemia) and dose-independent phenomena (e.g., pancreatitis), the former much more common than the latter. [See Adverse Reactions (6) .] Maximum antihypertensive effects are attained within 2 to 4 weeks after a change in dose. AVALIDE may be administered with or without food. AVALIDE may be administered with other antihypertensive agents. Renal Impairment The usual regimens of therapy with AVALIDE may be followed as long as the patient's creatinine clearance is >30 mL/min. In patients with more severe renal impairment, loop diuretics are preferred to thiazides, so AVALIDE is not recommended. Hepatic Impairment No dosage adjustment is necessary in patients with hepatic impairment. 2.2 Add-On Therapy In patients not controlled on monotherapy with irbesartan or hydrochlorothiazide, the recommended doses of AVALIDE, in order of increasing mean effect, are (irbesartan and hydrochlorothiazide) 150/12.5 mg, 300/12.5 mg, and 300/25 mg. The largest incremental effect will likely be in the transition from monotherapy to 150/12.5 mg. [See Clinical Studies (14.2) .] 2.3 Replacement Therapy AVALIDE may be substituted for the titrated components. 2.4 Initial Therapy The usual starting dose is AVALIDE 150/12.5 mg once daily. The dosage can be increased after 1 to 2 weeks of therapy to a maximum of 300/25 mg once daily as needed to control blood pressure [see Clinical Studies (14.2) ] . AVALIDE is not recommended as initial therapy in patients with intravascular volume depletion [see Warnings and Precautions (5.2) ] .

6 ADVERSE REACTIONS Most common adverse events (≥5% on AVALIDE and more often than on placebo) are dizziness, fatigue, and musculoskeletal pain. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact sanofi-aventis U.S. LLC at 1-800-633-1610 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. Irbesartan and Hydrochlorothiazide AVALIDE tablets have been evaluated for safety in 1694 patients treated for essential hypertension in 6 clinical trials. In Studies I through IV with AVALIDE, no adverse events peculiar to this combination drug product have been observed. Adverse events have been limited to those that were reported previously with irbesartan or hydrochlorothiazide (HCTZ). The overall incidence of adverse events was similar with the combination and placebo. In general, treatment with AVALIDE was well tolerated. For the most part, adverse events have been mild and transient in nature and have not required discontinuation of therapy. In controlled clinical trials, discontinuation of AVALIDE therapy due to clinical adverse events was required in only 3.6%. This incidence was significantly less (p=0.023) than the 6.8% of patients treated with placebo who discontinued therapy. In these double-blind controlled clinical trials, the following adverse events reported with AVALIDE occurred in ≥1% of patients, and more often on the irbesartan and hydrochlorothiazide combination than on placebo, regardless of drug relationship: Irbesartan/HCTZ (n=898) (%) Placebo (n=236) (%) Irbesartan (n=400) (%) HCTZ (n=380) (%) Body as a Whole Chest Pain 2 1 2 2 Fatigue 6 3 4 3 Influenza 3 1 2 2 Cardiovascular Edema 3 3 2 2 Tachycardia 1 0 1 1 Gastrointestinal Abdominal Pain 2 1 2 2 Dyspepsia/heartburn 2 1 0 2 Nausea/vomiting 3 0 2 2 Immunology Allergy 1 0 1 1 Musculoskeletal Musculoskeletal Pain 6 5 6 10 Nervous System Dizziness 8 4 6 5 Dizziness Orthostatic 1 0 1 1 Renal/Genitourinary Abnormality Urination 2 1 1 2 The following adverse events were also reported at a rate of 1% or greater, but were as, or more, common in the placebo group: headache, sinus abnormality, cough, URI, pharyngitis, diarrhea, rhinitis, urinary tract infection, rash, anxiety/nervousness, and muscle cramp. Adverse events occurred at about the same rates in men and women, older and younger patients, and black and non-black patients. Adverse events in Studies V and VI were similar to those described above in Studies I through IV. Irbesartan Other adverse events that have been reported with irbesartan, without regard to causality, are listed below: Body as a Whole: fever, chills, orthostatic effects, facial edema, upper extremity edema Cardiovascular: flushing, hypertension, cardiac murmur, myocardial infarction, angina pectoris, hypotension, syncope, arrhythmic/conduction disorder, cardiorespiratory arrest, heart failure, hypertensive crisis Dermatologic: pruritus, dermatitis, ecchymosis, erythema face, urticaria Endocrine/Metabolic/Electrolyte Imbalances: sexual dysfunction, libido change, gout Gastrointestinal: diarrhea, constipation, gastroenteritis, flatulence, abdominal distention Musculoskeletal/Connective Tissue: musculoskeletal trauma, extremity swelling, muscle cramp, arthritis, muscle ache, musculoskeletal chest pain, joint stiffness, bursitis, muscle weakness Nervous System: anxiety/nervousness, sleep disturbance, numbness, somnolence, vertigo, emotional disturbance, depression, paresthesia, tremor, transient ischemic attack, cerebrovascular accident Renal/Genitourinary: prostate disorder Respiratory: cough, upper respiratory infection, epistaxis, tracheobronchitis, congestion, pulmonary congestion, dyspnea, wheezing Special Senses: vision disturbance, hearing abnormality, ear infection, ear pain, conjunctivitis Hydrochlorothiazide Other adverse events that have been reported with hydrochlorothiazide, without regard to causality, are listed below: Body as a Whole: weakness Digestive: pancreatitis, jaundice (intrahepatic cholestatic jaundice), sialadenitis, cramping, gastric irritation Hematologic: aplastic anemia, agranulocytosis, leukopenia, hemolytic anemia, thrombocytopenia Hypersensitivity: purpura, photosensitivity, urticaria, necrotizing angiitis (vasculitis and cutaneous vasculitis), fever, respiratory distress including pneumonitis and pulmonary edema, anaphylactic reactions Metabolic: hyperglycemia, glycosuria, hyperuricemia Musculoskeletal: muscle spasm Nervous System/Psychiatric: restlessness Renal: renal failure, renal dysfunction, interstitial nephritis Skin: erythema multiforme including Stevens-Johnson syndrome, exfoliative dermatitis including toxic epidermal necrolysis Special Senses: transient blurred vision, xanthopsia Initial Therapy In the moderate hypertension Study V (mean SeDBP between 90 and 110 mmHg), the types and incidences of adverse events reported for patients treated with AVALIDE were similar to the adverse event profile in patients on initial irbesartan or HCTZ monotherapy. There were no reported events of syncope in the AVALIDE treatment group and there was one reported event in the HCTZ treatment group. The incidences of prespecified adverse events on AVALIDE, irbesartan, and HCTZ, respectively, were: 0.9%, 0%, and 0% for hypotension; 3.0%, 3.8%, and 1.0% for dizziness; 5.5%, 3.8%, and 4.8% for headache; 1.2%, 0%, and 1.0% for hyperkalemia; and 0.9%, 0%, and 0% for hypokalemia. The rates of discontinuation due to adverse events on AVALIDE, irbesartan alone, and HCTZ alone were 6.7%, 3.8%, and 4.8%. In the severe hypertension (SeDBP ≥110 mmHg) Study VI, the overall pattern of adverse events reported through 7 weeks of follow-up was similar in patients treated with AVALIDE as initial therapy and in patients treated with irbesartan as initial therapy. The incidences of the prespecified adverse events on AVALIDE and irbesartan, respectively, were: 0% and 0% for syncope; 0.6% and 0% for hypotension; 3.6% and 4.0% for dizziness; 4.3% and 6.6% for headache; 0.2% and 0% for hyperkalemia; and 0.6% and 0.4% for hypokalemia. The rates of discontinuation due to adverse events were 2.1% and 2.2%. [See Clinical Studies (14.2) .] 6.2 Postmarketing Experience The following adverse reactions have been identified during postapproval use of AVALIDE. 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. Decisions to include these reactions in labeling are typically based on one or more of the following factors: (1) seriousness of the reaction, (2) frequency of reporting, or (3) strength of causal connection to AVALIDE. Irbesartan and hydrochlorothiazide Blood and lymphatic system: Thrombocytopenia Hepatobiliary: Hepatitis, Jaundice Renal and urinary: Impaired renal function including renal failure Skin and subcutaneous tissue: Urticaria Irbesartan Blood and lymphatic system: Anemia Ear and labyrinth: Tinnitus Gastrointestinal: Intestinal angioedema Skin and subcutaneous tissue: Angioedema (involving swelling of the face, lips, pharynx, and/or tongue) Immune system: Anaphylactic reaction including anaphylactic shock Investigations: Increased CPK (Creatine Phosphokinase) Metabolism and nutrition: Hyperkalemia, Hypoglycemia in diabetic patients Hydrochlorothiazide Eye: Acute angle-closure glaucoma, Acute myopia, and Choroidal effusion Non-melanoma Skin Cancer Hydrochlorothiazide is associated with an increased risk of non-melanoma skin cancer. In a study conducted in the Sentinel System, increased risk was predominantly for squamous cell carcinoma (SCC) and in white patients taking large cumulative doses. The increased risk for SCC in the overall population was approximately 1 additional case per 16,000 patients per year, and for white patients taking a cumulative dose of ≥50,000 mg the risk increase was approximately 1 additional SCC case for every 6,700 patients per year. 6.3 Laboratory Abnormalities In controlled clinical trials, clinically important changes in standard laboratory parameters were rarely associated with administration of AVALIDE. Creatinine, Blood Urea Nitrogen: Minor increases in blood urea nitrogen (BUN) or serum creatinine were observed in 2.3% and 1.1%, respectively, of patients with essential hypertension treated with AVALIDE alone. No patient discontinued taking AVALIDE due to increased BUN. One patient discontinued taking AVALIDE due to a minor increase in serum creatinine. Liver Function Tests: Occasional elevations of liver enzymes and/or serum bilirubin have occurred. In patients with essential hypertension treated with AVALIDE alone, one patient was discontinued due to elevated liver enzymes. Serum Electrolytes: [See Warnings and Precautions (5.2 , 5.6) .]

12.3 Pharmacokinetics Irbesartan Irbesartan is an orally active agent that does not require biotransformation into an active form. The oral absorption of irbesartan is rapid and complete with an average absolute bioavailability of 60% to 80%. Following oral administration of irbesartan, peak plasma concentrations of irbesartan are attained at 1.5 to 2 hours after dosing. Food does not affect the bioavailability of irbesartan. Irbesartan exhibits linear pharmacokinetics over the therapeutic dose range. The terminal elimination half-life of irbesartan averaged 11 to 15 hours. Steady-state concentrations are achieved within 3 days. Limited accumulation of irbesartan (<20%) is observed in plasma upon repeated once-daily dosing. Hydrochlorothiazide When plasma levels have been followed for at least 24 hours, the plasma half-life has been observed to vary between 5.6 and 14.8 hours. Metabolism and Elimination Irbesartan Irbesartan is metabolized via glucuronide conjugation and oxidation. Following oral or intravenous administration of 14 C-labeled irbesartan, more than 80% of the circulating plasma radioactivity is attributable to unchanged irbesartan. The primary circulating metabolite is the inactive irbesartan glucuronide conjugate (approximately 6%). The remaining oxidative metabolites do not add appreciably to irbesartan's pharmacologic activity. Irbesartan and its metabolites are excreted by both biliary and renal routes. Following either oral or intravenous administration of 14 C-labeled irbesartan, about 20% of radioactivity is recovered in the urine and the remainder in the feces, as irbesartan or irbesartan glucuronide. In vitro studies of irbesartan oxidation by cytochrome P450 isoenzymes indicated irbesartan was oxidized primarily by 2C9; metabolism by 3A4 was negligible. Irbesartan was neither metabolized by, nor did it substantially induce or inhibit, isoenzymes commonly associated with drug metabolism (1A1, 1A2, 2A6, 2B6, 2D6, 2E1). There was no induction or inhibition of 3A4. Hydrochlorothiazide Hydrochlorothiazide is not metabolized but is eliminated rapidly by the kidney. At least 61% of the oral dose is eliminated unchanged within 24 hours. Distribution Irbesartan Irbesartan is 90% bound to serum proteins (primarily albumin and α 1 -acid glycoprotein) with negligible binding to cellular components of blood. The average volume of distribution is 53 to 93 liters. Total plasma and renal clearances are in the range of 157 to 176 mL/min and 3.0 to 3.5 mL/min, respectively. With repetitive dosing, irbesartan accumulates to no clinically relevant extent. Studies in animals indicate that radiolabeled irbesartan weakly crosses the blood-brain barrier and placenta. Irbesartan is excreted in the milk of lactating rats. Hydrochlorothiazide Hydrochlorothiazide crosses the placental but not the blood-brain barrier and is excreted in breast milk. Specific Populations Pediatric Irbesartan and hydrochlorothiazide pharmacokinetics have not been investigated in patients <18 years of age. Gender No gender-related differences in pharmacokinetics were observed in healthy elderly (age 65 to 80 years) or in healthy young (age 18 to 40 years) subjects. In studies of hypertensive patients, there was no gender difference in half-life or accumulation, but somewhat higher plasma concentrations of irbesartan were observed in females (11% to 44%). No gender-related dosage adjustment is necessary. Geriatric In elderly subjects (age 65 to 80 years), irbesartan elimination half-life was not significantly altered, but AUC and C max values were about 20% to 50% greater than those of young subjects (age 18 to 40 years). No dosage adjustment is necessary in the elderly. Race In healthy black subjects, irbesartan AUC values were approximately 25% greater than whites; there were no differences in C max values. Renal insufficiency The pharmacokinetics of irbesartan were not altered in patients with renal impairment or in patients on hemodialysis. Irbesartan is not removed by hemodialysis. No dosage adjustment is necessary in patients with mild to severe renal impairment unless a patient with renal impairment is also volume depleted. [See Warnings and Precautions (5.2) .] Hepatic insufficiency The pharmacokinetics of irbesartan following repeated oral administration were not significantly affected in patients with mild to moderate cirrhosis of the liver. No dosage adjustment is necessary in patients with hepatic insufficiency. Drug-Drug Interactions No significant drug-drug pharmacokinetic (or pharmacodynamic) interactions have been found in interaction studies with hydrochlorothiazide, digoxin, warfarin, and nifedipine. In vitro studies show significant inhibition of the formation of oxidized irbesartan metabolites with the known cytochrome CYP2C9 substrates/inhibitors sulphenazole, tolbutamide, and nifedipine. However, in clinical studies the consequences of concomitant irbesartan on the pharmacodynamics of warfarin were negligible. Concomitant nifedipine or hydrochlorothiazide had no effect on irbesartan pharmacokinetics. Based on in vitro data, no interaction would be expected with drugs whose metabolism is dependent upon cytochrome P450 isoenzymes 1A1, 1A2, 2A6, 2B6, 2D6, 2E1, or 3A4. In separate studies of patients receiving maintenance doses of warfarin, hydrochlorothiazide, or digoxin, irbesartan administration for 7 days had no effect on the pharmacodynamics of warfarin (prothrombin time) or the pharmacokinetics of digoxin. The pharmacokinetics of irbesartan were not affected by coadministration of nifedipine or hydrochlorothiazide.