Valsartan

INDICATIONS & USAGE Valsartan tablets are an angiotensin II receptor blocker (ARB) indicated for: • Hypertension , to lower blood pressure in adults and children 6 years and older. Lowering blood pressure reduces the risk of fatal and nonfatal cardiovascular events, primarily strokes and myocardial infarctions ( 1.1 ) • Heart failure (NYHA class II-IV), to reduce hospitalization for heart failure in adults ( 1.2 ) • Post-myocardial infarction , for the reduction of cardiovascular mortality in clinically stable patients with left ventricular failure or left ventricular dysfunction following myocardial infarction in adults ( 1.3 ) 1.1 Hypertension Valsartan tablets are indicated for the treatment of hypertension, to lower blood pressure in adults and pediatric patients six years of age and older . Lowering blood pressure reduces the risk of fatal and nonfatal 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 the class to which valsartan principally belongs. There are no controlled trials in hypertensive patients demonstrating risk reduction with valsartan tablets. 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 one 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 (e.g., 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 (e.g., on angina, heart failure, or diabetic kidney disease). These considerations may guide selection of therapy. Valsartan tablets may be used alone or in combination with other antihypertensive agents. Additional pediatric use information is approved for Novartis Pharmaceuticals Corporation's Diovan (valsartan) tablets. However, due to Novartis Pharmaceuticals Corporation's marketing exclusivity rights, this drug product is not labeled with that information. 1.2 Heart Failure Valsartan tablets are indicated to reduce the risk of hospitalization for heart failure in adult patients with heart failure (NYHA class II-IV). There is no evidence that valsartan tablets provides added benefits when it is used with an adequate dose of an angiotensin converting enzyme (ACE) inhibitor [see Clinical Studies ( 14.2 )]. 1.3 Post-Myocardial Infarction In clinically stable adult patients with left ventricular failure or left ventricular dysfunction following myocardial infarction, valsartan tablets are indicated to reduce the risk of cardiovascular mortality [see Clinical Studies ( 14.3 )].

DOSAGE AND ADMINISTRATION Indication Starting Dose Dose Range As tolerated by patient Hypertension Adults ( 2.2 ) 80 mg to 160 mg once daily 80 mg to 320 mg once daily 6 to 16 years ( 2.3 ) 1 mg/kg once daily Up to 40 mg daily 1 mg/kg to 4 mg/kg once daily Up to 160 mg daily Heart Failure ( 2.4 ) 40 mg twice daily 40mg to 160 mg twice daily Post-Myocardial Infarction ( 2.5 ) 20 mg twice daily 20 mg to160 mg twice daily 2.1 Important Dosage and Preparation Information Valsartan tablets and oral suspension are not substitutable on a milligram-per-milligram basis. Do not combine two dosage forms to achieve the total dose. The systemic exposure to valsartan (AUC) is 60% higher with the suspension compared to tablets [see Clinical Pharmacology (12.3) ] . Use of the oral suspension is recommended: in patients ≥ 6 years of age who cannot swallow tablets and in pediatric patients for whom the calculated dose (mg/kg) does not correspond to the available tablet strengths of valsartan. When switching between suspension and tablets, the dose of valsartan may need to be adjusted. Preparation of Suspension (for 160 mL of a 4 mg/mL suspension) Add 80 mL of Ora-Plus ® * oral suspending vehicle to an amber glass bottle containing 8 valsartan 80 mg tablets and shake for a minimum of 2 minutes. Allow the suspension to stand for a minimum of 1 hour. After the standing time, shake the suspension for a minimum of 1 additional minute. Add 80 mL of Ora-Sweet SF ® * oral sweetening vehicle to the bottle and shake the suspension for at least 10 seconds to disperse the ingredients. The suspension is homogenous and can be stored for either up to 30 days at room temperature (below 30°C/86°F) or up to 75 days at refrigerated conditions (2°C to 8°C/35°F to 46°F) in the glass bottle with a child-resistant screw-cap closure. Shake the bottle well (at least 10 seconds) prior to dispensing the suspension. *Ora-Sweet SF ® and Ora-Plus ® are registered trademarks of Paddock Laboratories, Inc. Additional pediatric use information is approved for Novartis Pharmaceuticals Corporation's Diovan (valsartan) tablets. However, due to Novartis Pharmaceuticals Corporation's marketing exclusivity rights, this drug product is not labeled with that information. 2.2 Adult Hypertension The recommended starting dose of valsartan tablets is 80 mg or 160 mg once daily when used as monotherapy in patients who are not volume-depleted. Patients requiring greater reductions may be started at the higher dose. Valsartan tablets may be used over a dose range of 80 mg to 320 mg daily, administered once a day. The antihypertensive effect is substantially present within 2 weeks and maximal reduction is generally attained after 4 weeks. If additional antihypertensive effect is required over the starting dose range, the dose may be increased to a maximum of 320 mg or a diuretic may be added. Addition of a diuretic has a greater effect than dose increases beyond 80 mg. Valsartan tablets may be administered with other antihypertensive agents. 2.3 Pediatric Hypertension 6 to 16 Years of Age The usual recommended starting dose is 1 mg/kg once daily (up to 40 mg total). A higher starting dose of 2 mg/kg may be considered in selected cases when a greater reduction of blood pressure is needed. The dosage should be adjusted according to blood pressure response and tolerability, up to a maximum dose of 4 mg/kg once daily (maximum daily dose 160 mg). No data are available in pediatric patients either undergoing dialysis or with a glomerular filtration rate <30 mL/min/1.73 m 2 [see Use in Specific Populations (8.4) ]. Use of valsartan tablets are not recommended in children less than 1 year of age [see Adverse Reactions (6.1) , Pediatric Use in Specific Populations (8.4) , Nonclinical Toxicology (13.2) ]. Additional pediatric use information is approved for Novartis Pharmaceuticals Corporation's Diovan (valsartan) tablets. However, due to Novartis Pharmaceuticals Corporation's marketing exclusivity rights, this drug product is not labeled with that information. 2.4 Heart Failure The recommended starting dose of valsartan tablets is 40 mg twice daily. Uptitrate to 80 mg and 160 mg twice daily or to the highest dose tolerated by the patient. Consider reducing the dose of concomitant diuretics. The maximum daily dose administered in clinical trials is 320 mg in divided doses. 2.5 Post-Myocardial Infarction Valsartan tablets may be initiated as early as 12 hours after a myocardial infarction. The recommended starting dose of valsartan tablets is 20 mg twice daily. Patients may be uptitrated within 7 days to 40 mg twice daily, with subsequent titrations to a target maintenance dose of 160 mg twice daily, as tolerated by the patient. If symptomatic hypotension or renal dysfunction occurs, consider dosage reduction. Valsartan tablets may be given with other standard post-myocardial infarction treatment, including thrombolytics, aspirin, beta-blockers, and statins. 2.6 Missed Dose If a dose of valsartan tablet is missed, it should be administered as soon as possible, unless it is almost time for the next dose. The dose should not be doubled to make up for a missed dose.

WARNINGS AND PRECAUTIONS Observe for signs and symptoms of hypotension (5.2) Monitor renal function and potassium in susceptible patients ( 5.3 , 5.4 ) 5.1 Fetal Toxicity Use of drugs that act on the renin-angiotensin system during the second and third trimesters of pregnancy reduces fetal renal function and increases fetal and neonatal morbidity and death. Resulting oligohydramnios can be associated with fetal lung hypoplasia and skeletal deformations. Potential neonatal adverse effects include skull hypoplasia, anuria, hypotension, renal failure, and death. When pregnancy is detected, discontinue Valsartan Oral Solution as soon as possible [see Use in Specific Populations (8.1) ]. 5.2 Hypotension In patients with an activated renin-angiotensin system, such as volume- and/or salt-depleted patients receiving high doses of diuretics, symptomatic hypotension may occur. This condition should be corrected prior to administration of valsartan, or the treatment should start under close medical supervision. Peak plasma concentrations of valsartan are higher following administration of Valsartan Oral Solution and may result in increased risk of hypotension as compared to administration of valsartan tablets [see Clinical Pharmacology (12.3) ] . Patients with heart failure or post-myocardial infarction patients given valsartan tablets in clinical trials commonly had some reduction in blood pressure. Only use Valsartan Oral Solution in heart failure or post-myocardial infarction patients who are unable to swallow valsartan tablets. In clinical trials of valsartan tablets, discontinuation of therapy because of continuing symptomatic hypotension usually was not necessary. In controlled trials in heart failure patients, the incidence of hypotension in valsartan-treated patients was 5.5% compared to 1.8% in placebo-treated patients. In the Valsartan in Acute Myocardial Infarction Trial (VALIANT), hypotension in post- myocardial infarction patients led to permanent discontinuation of therapy in 1.4% of valsartan-treated patients and 0.8% of captopril-treated patients. If symptomatic hypotension occurs, place the patient in the supine position and, if necessary, give an intravenous infusion of normal saline. A transient hypotensive response is not a contraindication to further treatment, which usually can be continued without difficulty once the blood pressure has stabilized. 5.3 Impaired Renal Function Changes in renal function including acute renal failure can be caused by drugs that inhibit the renin-angiotensin system and by diuretics. Patients whose renal function may depend in part on the activity of the renin-angiotensin system (e.g., patients with renal artery stenosis, chronic kidney disease, severe congestive heart failure, or volume depletion) may be at particular risk of developing acute renal failure on valsartan. Monitor renal function periodically in these patients. Consider withholding or discontinuing therapy in patients who develop a clinically significant decrease in renal function on valsartan [see Drug Interactions (7) ]. 5.4 Hyperkalemia Some patients with heart failure have developed increases in potassium. These effects are usually minor and transient, and they are more likely to occur in patients with pre-existing renal impairment. Dosage reduction and/or discontinuation of Valsartan Oral Solution may be required [see Adverse Reactions (6.1) ].

CONTRAINDICATIONS Do not use in patients with known hypersensitivity to any component. Do not coadminister aliskiren with valsartan tablets in patients with diabetes [see Drug Interactions ( 7.3 )]. Known hypersensitivity to any component. Do not coadminister aliskiren with valsartan tablets in patients with diabetes ( 4 )

DRUG INTERACTIONS No clinically significant pharmacokinetic interactions were observed when valsartan tablets was coadministered with amlodipine, atenolol, cimetidine, digoxin, furosemide, glyburide, hydrochlorothiazide, or indomethacin. The valsartan-atenolol combination was more antihypertensive than either component, but it did not lower the heart rate more than atenolol alone. Coadministration of valsartan and warfarin did not change the pharmacokinetics of valsartan or the time-course of the anticoagulant properties of warfarin. CYP 450 Interactions: In vitro metabolism studies indicate that CYP 450 mediated drug interactions between valsartan and coadministered drugs are unlikely because of the low extent of metabolism [see Clinical Pharmacology (12.3)]. Transporters: The results from an in vitro study with human liver tissue indicate that valsartan is a substrate of the hepatic uptake transporter OATP1B1 and the hepatic efflux transporter MRP2. Co-administration of inhibitors of the uptake transporter (rifampin, cyclosporine) or efflux transporter (ritonavir) may increase the systemic exposure to valsartan. Potassium: Concomitant use of valsartan with other agents that block the renin-angiotensin system, potassium sparing diuretics (e.g. spironolactone, triamterene, amiloride), potassium supplements, or salt substitutes containing potassium may lead to increases in serum potassium and in heart failure patients to increases in serum creatinine. If co-medication is considered necessary, monitoring of serum potassium is advisable. Non-Steroidal Anti-Inflammatory Agents including Selective Cyclooxygenase-2 Inhibitors (COX-2 Inhibitors): In patients who are elderly, volume-depleted (including those on diuretic therapy), or with compromised renal function, coadministration of NSAIDs, including selective COX-2 inhibitors, with angiotensin II receptor antagonists, including valsartan, may result in deterioration of renal function, including possible acute renal failure. These effects are usually reversible. Monitor renal function periodically in patients receiving valsartan and NSAID therapy. The antihypertensive effect of angiotensin II receptor antagonists, including valsartan may be attenuated by NSAIDs including selective COX-2 inhibitors. Dual Blockade of the Renin-Angiotensin System (RAS): Dual blockade of the RAS with angiotensin receptor blockers, ACE inhibitors, or aliskiren is associated with increased risks of hypotension, hyperkalemia, and changes in renal function (including acute renal failure) compared to monotherapy. Most patients receiving the combination of two RAS inhibitors do not obtain any additional benefit compared to monotherapy. In general, avoid combined use of RAS inhibitors. Closely monitor blood pressure, renal function and electrolytes in patients on valsartan tablets and other agents that affect the RAS. Do not coadminister aliskiren with valsartan tablets in patients with diabetes. Avoid use of aliskiren with valsartan tablets in patients with renal impairment (GFR <60 mL/min). Lithium: Increases in serum lithium concentrations and lithium toxicity have been reported during concomitant administration of lithium with angiotensin II receptor antagonists, including valsartan tablets. Monitor serum lithium levels during concomitant use. Potassium sparing diuretics, potassium supplements or salt substitutes may lead to increases in serum potassium, and in heart failure patients, increases in serum creatinine (7 NSAID use may lead to increased risk of renal impairment and loss of antihypertensive effect (7) Dual inhibition of the renin-angiotensin system: Increased risk of renal impairment, hypotension, and hyperkalemia (7) Lithium: Increases in serum lithium concentrations and lithium toxicity 7.1 Clinical Laboratory Test Findings In controlled clinical trials, clinically important changes in standard laboratory parameters were rarely associated with administration of valsartan tablets. Creatinine: Minor elevations in creatinine occurred in 0.8% of patients taking valsartan tabletsand 0.6% given placebo in controlled clinical trials of hypertensive patients. In heart failure trials, greater than 50% increases in creatinine were observed in 3.9% of valsartan tablets-treated patients compared to 0.9% of placebo-treated patients. Hemoglobin and Hematocrit: Greater than 20% decreases in hemoglobin and hematocrit were observed in 0.4% and 0.8%, respectively, of valsartan tablets patients, compared with 0.1% and 0.1% in placebo-treated patients. One valsartan patient discontinued treatment for microcytic anemia. Liver Function Tests: Occasional elevations (greater than 150%) of liver chemistries occurred in valsartan tablets-treated patients. Three patients (< 0.1%) treated with valsartan discontinued treatment for elevated liver chemistries. Neutropenia: Neutropenia was observed in 1.9% of patients treated with valsartan tablets and 0.8% of patients treated with placebo. Serum Potassium: In hypertensive patients, greater than 20% increases in serum potassium were observed in 4.4% ofvalsartan tablets-treated patients compared to 2.9% of placebo-treated patients. In heart failure patients, greater than 20% increases in serum potassium were observed in 10% of valsartan tablets-treated patients compared to 5.1% of placebo-treated patients. Blood Urea Nitrogen (BUN): In heart failure trials, greater than 50% increases in BUN were observed in 16.6% of valsartan tablets-treated patients compared to 6.3% of placebo-treated patients.

ADVERSE REACTIONS Hypertension: Most common adverse reactions are headache, dizziness, fatigue and abdominal pain (6.1) Heart Failure: Most common adverse reactions are dizziness, hypotension, diarrhea, arthralgia, back pain, fatigue and hyperkalemia (6.1) Post-Myocardial Infarction: Most common adverse reactions which caused patients to discontinue therapy are hypotension, cough and increased blood creatinine (6.1) To report SUSPECTED ADVERSE REACTIONS, contact Lifsa Drugs LLC at 1-800-223-1467 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Studies Experience Because clinical studies are conducted under widely varying conditions, adverse reaction rates observed in the clinical studies of a drug cannot be directly compared to rates in the clinical studies of another drug and may not reflect the rates observed in practice. Adult Hypertension Valsartan has been evaluated for safety in more than 4,000 patients, including over 400 treated for over 6 months, and more than 160 for over 1 year. Adverse reactions have generally been mild and transient in nature and have only infrequently required discontinuation of therapy. The overall incidence of adverse reactions with valsartan was similar to placebo. The overall frequency of adverse reactions was neither dose-related nor related to gender, age, race, or regimen. Discontinuation of therapy due to side effects was required in 2.3% of valsartan patients and 2.0% of placebo patients. The most common reasons for discontinuation of therapy with valsartan were headache and dizziness. The adverse reactions that occurred in placebo-controlled clinical trials in at least 1% of patients treated with valsartan and at a higher incidence in valsartan (n=2,316) than placebo (n=888) patients included fatigue (2% vs. 1%) and abdominal pain (2% vs. 1%). Headache, dizziness, upper respiratory infection, cough, diarrhea, rhinitis, sinusitis, nausea, pharyngitis, edema, and arthralgia occurred at a more than 1% rate, but at about the same incidence in placebo and valsartan patients. In trials in which valsartan was compared to an ACE inhibitor with or without placebo, the incidence of dry cough was significantly greater in the ACE-inhibitor group (7.9%) than in the groups who received valsartan (2.6%) or placebo (1.5%). In a 129-patient trial limited to patients who had dry cough when they had previously received ACE inhibitors, the incidences of cough in patients who received valsartan, HCTZ, or lisinopril were 20%, 19%, and 69% respectively (p <0.001). Dose-related orthostatic effects were seen in less than 1% of patients. An increase in the incidence of dizziness was observed in patients treated with valsartan 320 mg (8%) compared to 10 to 160 mg (2% to 4%). Valsartan has been used concomitantly with hydrochlorothiazide without evidence of clinically important adverse interactions. Other adverse reactions that occurred in controlled clinical trials of patients treated with valsartan (>0.2% of valsartan patients) are listed below. It cannot be determined whether these events were causally related to valsartan. Body as a Whole: Allergic reaction and asthenia Cardiovascular: Palpitations Dermatologic: Pruritus and rash Digestive: Constipation, dry mouth, dyspepsia and flatulence Musculoskeletal: Backpain, muscle cramps, and myalgia Neurologic and Psychiatric: Anxiety, insomnia, paresthesia, and somnolence Respiratory: Dyspnea Special Senses: Vertigo Urogenital: Impotence Other reported events seen less frequently in clinical trials included chest pain, syncope, anorexia, vomiting, and angioedema. Pediatric Hypertension Valsartan has been evaluated for safety in over 400 pediatric patients aged 6 to 17 years and more than 160 pediatric patients aged 6 months to 5 years. No relevant differences were identified between the adverse experience profile for pediatric patients aged 6 to 16 years and that previously reported for adult patients. Headache and hyperkalemia were the most common adverse events suspected to be study drug-related in older children (6 to 17 years old) and younger children (6 months to 5 years old), respectively. Hyperkalemia was mainly observed in children with underlying renal disease. Neurocognitive and developmental assessment of pediatric patients aged 6 to 16 years revealed no overall clinically relevant adverse impact after treatment with valsartan for up to 1 year. Valsartan is not recommended for pediatric patients under 6 years of age. In a study (n=90) of pediatric patients (1 to 5 years), two deaths and three cases of on-treatment transaminase elevations were seen in the one-year open-label extension phase. These 5 events occurred in a study population in which patients frequently had significant co-morbidities. A causal relationship to valsartan has not been established. In a second study of 6-months duration in 75 children aged 1 to 5 years, there were no deaths; one case of marked liver transaminase elevations occurred following 6 months of treatment. Heart Failure The adverse experience profile of valsartan in heart failure patients was consistent with the pharmacology of the drug and the health status of the patients. In the Valsartan Heart Failure Trial, comparing valsartan in total daily doses up to 320 mg (n=2,506) to placebo (n=2,494), 10% of valsartan patients discontinued for adverse reactions vs. 7% of placebo patients. The table shows adverse reactions in double-blind short-term heart failure trials, including the first 4 months of the Valsartan Heart Failure Trial, with an incidence of at least 2% that were more frequent in valsartan-treated patients than in placebo-treated patients. All patients received standard drug therapy for heart failure, frequently as multiple medications, which could include diuretics, digitalis, beta-blockers. About 93% of patients received concomitant ACE inhibitors. V a l s a r t a n (n=3,282) Placebo (n=2,740) Dizziness 17% 9% Hypotension 7% 2% Diarrhea 5% 4% Arthralgia 3% 2% Fatigue 3% 2% Back Pain 3% 2% Dizziness, postural 2% 1% Hyperkalemia 2% 1% Hypotension, postural 2% 1% Discontinuations occurred in 0.5% of valsartan-treated patients and 0.1% of placebo patients for each of the following: elevations in creatinine and elevations in potassium. Other adverse reactions with an incidence greater than 1% and greater than placebo included headache, nausea, renal impairment, syncope, blurred vision, upper abdominal pain and vertigo. From the long-term data in the Valsartan Heart Failure Trial, there did not appear to be any significant adverse reactions not previously identified. Post-Myocardial Infarction The safety profile of valsartan was consistent with the pharmacology of the drug and the background diseases, cardiovascular risk factors, and clinical course of patients treated in the post-myocardial infarction setting. The table shows the percentage of patients discontinued in the valsartan and captopril-treated groups in the Valsartan in Acute Myocardial Infarction Trial (VALIANT) with a rate of at least 0.5% in either of the treatment groups. Discontinuations due to renal dysfunction occurred in 1.1% of valsartan-treated patients and 0.8% of captopril-treated patients. Valsartan (n=4,885) Captopril (n=4,879) Discontinuation for adverse reaction 5.8% 7.7% Adverse reactions Hypotension NOS 1.4% 0.8% Cough 0.6% 2.5% Blood creatinine increased 0.6% 0.4% Rash NOS 0.2% 0.6% In controlled clinical trials, clinically important changes in standard laboratory parameters were rarely associated with administration of valsartan. Creatinine: Minor elevations in creatinine occurred in 0.8% of patients taking valsartan and 0.6% given placebo in controlled clinical trials of hypertensive patients. In heart failure trials, greater than 50% increases in creatinine were observed in 3.9% of valsartan-treated patients compared to 0.9% of placebo-treated patients. In post-myocardial infarction patients, doubling of serum creatinine was observed in 4.2%

CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Angiotensin II is formed from angiotensin I in a reaction catalyzed by angiotensin-converting enzyme (ACE, kininase II). Angiotensin II is the principal pressor agent of the renin-angiotensin system, with effects that include vasoconstriction, stimulation of synthesis and release of aldosterone, cardiac stimulation, and renal reabsorption of sodium. Valsartan blocks the vasoconstrictor and aldosterone-secreting effects of angiotensin II by selectively blocking the binding of angiotensin II to the AT 1 receptor in many tissues, such as vascular smooth muscle and the adrenal gland. Its action is therefore independent of the pathways for angiotensin II synthesis. There is also an AT 2 receptor found in many tissues, but AT 2 is not known to be associated with cardiovascular homeostasis. Valsartan has much greater affinity (about 20,000-fold) for the AT 1 receptor than for the AT 2 receptor. The increased plasma levels of angiotensin II following AT 1 receptor blockade with valsartan may stimulate the unblocked AT 2 receptor. The primary metabolite of valsartan is essentially inactive with an affinity for the AT 1 receptor about one-200 th (1/200 th ) that of valsartan itself. Blockade of the renin-angiotensin system with ACE inhibitors, which inhibit the biosynthesis of angiotensin II from angiotensin I, is widely used in the treatment of hypertension. ACE inhibitors also inhibit the degradation of bradykinin, a reaction also catalyzed by ACE. Because valsartan does not inhibit ACE (kininase II), it does not affect the response to bradykinin. Whether this difference has clinical relevance is not yet known. Valsartan does not bind to or block other hormone receptors or ion channels known to be important in cardiovascular regulation. Blockade of the angiotensin II receptor inhibits the negative regulatory feedback of angiotensin II on renin secretion, but the resulting increased plasma renin activity and angiotensin II circulating levels do not overcome the effect of valsartan on blood pressure. 12.2 Pharmacodynamics Valsartan inhibits the pressor effect of angiotensin II infusions. An oral dose of 80 mg inhibits the pressor effect by about 80% at peak with approximately 30% inhibition persisting for 24 hours. No information on the effect of larger doses is available. Removal of the negative feedback of angiotensin II causes a 2- to 3-fold rise in plasma renin and consequent rise in angiotensin II plasma concentration in hypertensive patients. Minimal decreases in plasma aldosterone were observed after administration of valsartan; very little effect on serum potassium was observed. In multiple-dose studies in hypertensive patients with stable renal insufficiency and patients with renovascular hypertension, valsartan had no clinically significant effects on glomerular filtration rate, filtration fraction, creatinine clearance, or renal plasma flow. In multiple-dose studies in hypertensive patients, valsartan had no notable effects on total cholesterol, fasting triglycerides, fasting serum glucose, or uric acid. 12.3 Pharmacokinetics Absorption In healthy volunteers, valsartan peak plasma concentration is reached 2 to 4 hours after dosing. Valsartan shows bi-exponential decay kinetics following intravenous administration, with an average elimination half-life of about 6 hours. Absolute bioavailability for valsartan is about 25% (range 10% to 35%). The bioavailability of the suspension [see Dosage and Administration (2.2) ] is 1.6 times as great as with the tablet. AUC and C max values of valsartan increase approximately linearly with increasing dose over the clinical dosing range (80 mg to 320 mg). Valsartan does not accumulate appreciably in plasma following repeated administration of 200 mg once daily. In heart failure patients, the average time to peak plasma concentration and elimination half-life of valsartan are similar to those observed in healthy volunteers. The average accumulation factor is about 1.7 in heart failure patients following repeated administration of 160 mg twice daily. AUC and C max values of valsartan increase linearly and are almost proportional with increasing dose from 40 mg to 160 mg twice a day. Effect of Food With the tablet, food decreases the exposure (as measured by AUC) to valsartan by about 40% and peak plasma concentration (C max ) by about 50%. Valsartan tablets can be administered with or without food. Distribution: The steady state volume of distribution of valsartan after intravenous administration is small (17 L), indicating that valsartan does not distribute into tissues extensively. Valsartan is highly bound to serum proteins (95%), mainly serum albumin. Metabolism: The primary metabolite, accounting for about 9% of dose, is valeryl 4-hydroxy valsartan. In vitro metabolism studies involving recombinant CYP 450 enzymes indicated that the CYP 2C9 isoenzyme is responsible for the formation of valeryl-4-hydroxy valsartan. Valsartan does not inhibit CYP 450 isozymes at clinically relevant concentrations. CYP 450 mediated drug interaction between valsartan and coadministered drugs are unlikely because of the low extent of metabolism. Excretion Valsartan, when administered as an oral solution, is primarily recovered in feces (about 83% of dose) and urine (about 13% of dose). The recovery is mainly as unchanged drug, with only about 20% of dose recovered as metabolites. Following intravenous administration, plasma clearance of valsartan is about 2 L/h and its renal clearance is 0.62 L/h (about 30% of total clearance). The apparent clearance of valsartan following oral administration is approximately 4.5 L/h in heart failure patients. Age does not affect the apparent clearance in heart failure patients. Specific Populations: Geriatric: Exposure (measured by AUC) to valsartan is higher by 70% and the half-life is longer by 35% in the elderly than in the young. [see Use in Specific Populations (8.5) ] . Pediatric: In a study of pediatric hypertensive patients (n=26, 1 to 16 years of age) given single doses of a suspension of valsartan (mean: 0.9 mg/kg to 2 mg/kg), the clearance (L/h/kg) of valsartan for children was similar to that of adults receiving the same formulation. Valsartan pharmacokinetics have not been investigated in pediatric patients less than 1 year of age. Gender: Pharmacokinetics of valsartan does not differ significantly between males and females. Renal Insufficiency: There is no apparent correlation between renal function (measured by creatinine clearance) and exposure (measured by AUC) to valsartan in patients with different degrees of renal impairment (down to creatinine clearance of 10 mL/min). Valsartan is not removed from the plasma by hemodialysis [see Use in Specific Populations (8.6) ]. Hepatic Insufficiency: On average, patients with mild-to-moderate chronic liver disease have twice the exposure (measured by AUC values) to valsartan of healthy volunteers (matched by age, sex, and weight) [see Use in Specific Populations (8.7) ] . Drug Interaction Studies No clinically significant pharmacokinetic interactions were observed when valsartan was coadministered with amlodipine, atenolol, cimetidine, digoxin, furosemide, glyburide, hydrochlorothiazide, or indomethacin. The valsartan-atenolol combination was more antihypertensive than either component, but it did not lower the heart rate more than atenolol alone. Coadministration of valsartan and warfarin did not change the pharmacokinetics of valsartan or the time-course of the anticoagulant properties of warfarin. Transporters: The results from an in vitro study with human liver tissue indicate that valsartan is a substrate of the hepatic uptake transporter OATP1B1 and the hepatic efflux transporter MRP2. Coadministration of inhibitors of the uptake transporter (rifampin, cyclosporine) or efflux transporter (ritonavir) may increase the systemic exposure to valsartan.