TOLVAPTAN

1 INDICATIONS AND USAGE Tolvaptan tablets are indicated for the treatment of clinically significant hypervolemic and euvolemic hyponatremia (serum sodium <125 mEq/L or less marked hyponatremia that is symptomatic and has resisted correction with fluid restriction), including patients with heart failure and Syndrome of Inappropriate Antidiuretic Hormone (SIADH). Limitations of Use Patients requiring intervention to raise serum sodium urgently to prevent or to treat serious neurological symptoms should not be treated with tolvaptan tablets. It has not been established that raising serum sodium with tolvaptan tablets provides a symptomatic benefit to patients. Tolvaptan tablets are a selective vasopressin V 2 -receptor antagonist indicated for the treatment of clinically significant hypervolemic and euvolemic hyponatremia [serum sodium <125 mEq/L or less marked hyponatremia that is symptomatic and has resisted correction with fluid restriction], including patients with heart failure and Syndrome of Inappropriate Antidiuretic Hormone (SIADH) ( 1 ) Limitations of Use: Patients requiring intervention to raise serum sodium urgently to prevent or to treat serious neurological symptoms should not be treated with tolvaptan tablets ( 1 ) It has not been established that tolvaptan tablets provides a symptomatic benefit to patients ( 1 )

2 DOSAGE AND ADMINISTRATION Tolvaptan tablets should be initiated and re-initiated in a hospital ( 2.1 ) The recommended starting dose is 15 mg once daily. Dosage may be increased at intervals ≥24 hr to 30 mg once daily, and to a maximum of 60 mg once daily as needed to raise serum sodium. ( 2.1 ) 2.1 Recommended Dosage Patients should be in a hospital for initiation and re-initiation of therapy to evaluate the therapeutic response and because too rapid correction of hyponatremia can cause osmotic demyelination resulting in dysarthria, mutism, dysphagia, lethargy, affective changes, spastic quadriparesis, seizures, coma and death. The usual starting dose for tolvaptan tablets is 15 mg administered once daily without regard to meals. Increase the dose to 30 mg once daily, after at least 24 hours, to a maximum of 60 mg once daily, as needed to achieve the desired level of serum sodium. Do not administer tolvaptan tablets for more than 30 days to minimize the risk of liver injury [ see Warnings and Precautions (5.2) ]. During initiation and titration, frequently monitor for changes in serum electrolytes and volume. Avoid fluid restriction during the first 24 hours of therapy. Patients receiving tolvaptan tablets should be advised that they can continue ingestion of fluid in response to thirst [ see Warnings and Precautions (5.1) ]. 2.2 Drug Withdrawal Following discontinuation from tolvaptan tablets, patients should be advised to resume fluid restriction and should be monitored for changes in serum sodium and volume status.

5 WARNINGS AND PRECAUTIONS Liver injury: Limit treatment duration to 30 days. If hepatic injury is suspected, discontinue tolvaptan. Avoid use in patients with underlying liver disease ( 5.2 ) Dehydration and hypovolemia may require intervention ( 5.3 ) Avoid use with hypertonic saline ( 5.4 ) Avoid use with moderate to strong CYP3A inhibitors ( 5.5 ) Monitor serum potassium in patients with potassium >5 mEq/L or on drugs known to increase potassium ( 5.6 ) Urinary outflow obstruction: Urinary output must be secured ( 5.7 ) 5.1 Too Rapid Correction of Serum Sodium Can Cause Serious Neurologic Sequelae Osmotic demyelination syndrome is a risk associated with too rapid correction of hyponatremia (e.g.,>12 mEq/L/24 hours). Osmotic demyelination results in dysarthria, mutism, dysphagia, lethargy, affective changes, spastic quadriparesis, seizures, coma or death. In susceptible patients, including those with severe malnutrition, alcoholism or advanced liver disease, slower rates of correction may be advisable. In controlled clinical trials in which tolvaptan was administered in titrated doses starting at 15 mg once daily, 7% of tolvaptan-­treated subjects with a serum sodium <130 mEq/L had an increase in serum sodium greater than 8 mEq/L at approximately 8 hours and 2% had an increase greater than 12 mEq/L at 24 hours. Approximately 1% of placebo-treated subjects with a serum sodium <130 mEq/L had a rise greater than 8 mEq/L at 8 hours and no patient had a rise greater than 12 mEq/L/24 hours. Osmotic demyelination syndrome has been reported in association with tolvaptan therapy [see Adverse Reactions (6.2) ] . Patients treated with tolvaptan should be monitored to assess serum sodium concentrations and neurologic status, especially during initiation and after titration. Subjects with SIADH or very low baseline serum sodium concentrations may be at greater risk for too-rapid correction of serum sodium. In patients receiving tolvaptan who develop too rapid a rise in serum sodium, discontinue or interrupt treatment with tolvaptan and consider administration of hypotonic fluid. Fluid restriction during the first 24 hours of therapy with tolvaptan may increase the likelihood of overly rapid correction of serum sodium and should generally be avoided. Co-administration of diuretics also increases the risk of too rapid correction of serum sodium and such patients should undergo close monitoring of serum sodium. 5.2 Liver Injury Tolvaptan can cause serious and potentially fatal liver injury. In placebo-controlled studies and an open-label extension study of chronically administered tolvaptan in patients with ADPKD, cases of serious liver injury attributed to tolvaptan, generally occurring during the first 18 months of therapy, were observed. In postmarketing experience with tolvaptan in ADPKD, acute injury resulting in liver failure requiring liver transplantation has been reported. Tolvaptan should not be used to treat ADPKD outside of the FDA-approved risk evaluation and mitigation strategy (REMS) for ADPKD patients [see Contraindications (4) ]. Patients with symptoms that may indicate liver injury, including fatigue, anorexia, right upper abdominal discomfort, dark urine or jaundice should discontinue treatment with tolvaptan. Limit duration of therapy with tolvaptan to 30 days. Avoid use in patients with underlying liver disease, including cirrhosis, because the ability to recover from liver injury may be impaired [see Adverse Reactions (6.1) ]. 5.3 Dehydration and Hypovolemia Tolvaptan therapy induces copious aquaresis, which is normally partially offset by fluid intake. Dehydration and hypovolemia can occur, especially in potentially volume-depleted patients receiving diuretics or those who are fluid restricted. In multiple-dose, placebo-controlled trials in which 607 hyponatremic patients were treated with tolvaptan, the incidence of dehydration was 3.3% for tolvaptan and 1.5% for placebo-treated patients. In patients receiving tolva…

4 CONTRAINDICATIONS Tolvaptan tablets are contraindicated in the following conditions: • Patients with autosomal dominant polycystic kidney disease (ADPKD) outside of FDA-approved REMS [see Warnings and Precautions (5.2) ] • Unable to sense or respond to thirst • Hypovolemic hyponatremia • Taking strong CYP3A inhibitors [see Warnings and Precautions (5.5) ] • Anuria • Hypersensitivity (e.g., anaphylactic shock, rash generalized) to tolvaptan or any components of the product [see Adverse Reactions (6) ] Use in patients with autosomal dominant polycystic kidney disease (ADPKD) outside of FDA-approved REMS ( 4 ) Patients who are unable to respond appropriately to thirst ( 4 ) Hypovolemic hyponatremia ( 4 ) Concomitant use of strong CYP3A inhibitors ( 4 ) Anuria ( 4 ) Hypersensitivity ( 4 )

7 DRUG INTERACTIONS Avoid concomitant use with: Moderate CYP3A inhibitors ( 7.1 ) Strong CYP3A inducers ( 7.1 ) V 2 -receptor antagonists ( 7.3 ) Monitor serum potassium during concomitant therapy with ( 7.2 ): Angiotensin receptor blockers Angiotensin converting enzyme inhibitors Potassium sparing diuretics 7.1 CYP3A Inhibitors and Inducers Strong CYP3A Inhibitors Tolvaptan's AUC was 5.4 times as large and Cmax was 3.5 times as large after co-administration of tolvaptan and 200 mg ketoconazole [see Warnings and Precautions (5.5) and Clinical Pharmacology (12.3) ] . Larger doses of the strong CYP3A inhibitor would be expected to produce larger increases in tolvaptan exposure. Concomitant use of tolvaptan with strong CYP3A inhibitors is contraindicated [see Contraindications (4) ] . Moderate CYP3A Inhibitors A substantial increase in the exposure to tolvaptan would be expected when tolvaptan is co-administered with moderate CYP3A inhibitors. Avoid co-administration of tolvaptan with moderate CYP3A inhibitors [see Warnings and Precautions (5.5)] . Patients should avoid grapefruit juice beverages while taking tolvaptan [see Clinical Pharmacology (12.3) ] . Strong CYP3A Inducers Co-administration of tolvaptan with strong CYP3A inducers reduces exposure to tolvaptan [see Clinical Pharmacology (12.3) ] . Avoid concomitant use of tolvaptan with strong CYP3A inducers. 7.2 Angiotensin Receptor Blockers, Angiotensin Converting Enzyme Inhibitors and Potassium Sparing Diuretics Although specific interaction studies were not performed, in clinical studies, tolvaptan was used concomitantly with beta-blockers, angiotensin receptor blockers, angiotensin converting enzyme inhibitors and potassium sparing diuretics. Adverse reactions of hyperkalemia were approximately 1 to 2% higher when tolvaptan was administered with angiotensin receptor blockers, angiotensin converting enzyme inhibitors and potassium sparing diuretics compared to administration of these medications with placebo. Serum potassium levels should be monitored during concomitant drug therapy. 7.3 V2-Receptor Agonist As a V 2 -receptor antagonist, tolvaptan may interfere with the V 2 -agonist activity of desmopressin (dDAVP). Avoid concomitant use of tolvaptan with a V 2 -agonist.

8.1 Pregnancy Risk Summary Available data with tolvaptan use in pregnant women are insufficient to determine if there is a drug-associated risk of adverse developmental outcomes. Tolvaptan did not cause any developmental toxicity in rats or in rabbits at exposures approximately 2.8 and 0.8 times, respectively, the exposure in congestive heart failure (CHF) patients at the maximum recommended human dose (MRHD) of 60 mg once daily. However, effects on embryo-fetal development occurred in both species at doses causing significant maternally toxic doses. In rats, reduced fetal weights and delayed fetal ossification occurred at 11 times the exposure in CHF patients, based on AUC. In rabbits, increased abortions, embryo-fetal death, fetal microphthalmia, open eyelids, cleft palate, brachymelia and skeletal malformations occurred at approximately 1.6 times the exposure in CHF patients (see Data) . The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. The estimated background risk of major birth defects and miscarriage in the U.S. general population is 2 to 4% and 15 to 20% of clinically recognized pregnancies, respectively. Data Animal Data Oral administration of tolvaptan during the period of organogenesis in Sprague-Dawley rats produced no evidence of teratogenesis at doses up to 100 mg/kg/day. Delayed ossification was seen at 1000 mg/kg, which is approximately 11 times the exposure in CHF patients at the MRHD of 60 mg (AUC 24h 10271 ng*h/mL). The fetal effects are likely secondary to maternal toxicity (decreased food intake and low body weights). In a prenatal and postnatal study in rats, tolvaptan had no effect on physical development, reflex function, learning ability or reproductive performance at doses up to 1000 mg/kg/day (11 times the exposure in CHF patients at the MRHD of 60 mg). In rabbits, teratogenicity (microphthalmia, embryo-fetal mortality, cleft palate, brachymelia and skeletal malformations) was observed in rabbits at 1000 mg/kg (approximately 1.6 times the exposure in CHF patients at the MRHD of 60 mg dose). This dose also caused maternal toxicity (lower body weight gains and food consumption).

6 ADVERSE REACTIONS Most common adverse reactions (≥5% placebo) are thirst, dry mouth, asthenia, constipation, pollakiuria or polyuria, and hyperglycemia ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Northstar RxLLC at 1-800-206-7821 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 reactions 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 event 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. In multiple-dose, placebo-controlled trials, 607 hyponatremic patients (serum sodium <135 mEq/L) were treated with tolvaptan. The mean age of these patients was 62 years; 70% of patients were male and 82% were Caucasian. One hundred eighty-nine (189) tolvaptan-treated patients had a serum sodium <130 mEq/L, and 52 patients had a serum sodium <125 mEq/L. Hyponatremia was attributed to cirrhosis in 17% of patients, heart failure in 68% and SIADH/other in 16%. Of these patients, 223 were treated with the recommended dose titration (15 mg titrated to 60 mg as needed to raise serum sodium). Overall, over 4,000 patients have been treated with oral doses of tolvaptan in open-label or placebo-controlled clinical trials. Approximately 650 of these patients had hyponatremia; approximately 219 of these hyponatremic patients were treated with tolvaptan for 6 months or more. The most common adverse reactions (incidence ≥5% more than placebo) seen in two 30-day, double-blind, placebo-controlled hyponatremia trials in which tolvaptan was administered in titrated doses (15 mg to 60 mg once daily) were thirst, dry mouth, asthenia, constipation, pollakiuria or polyuria and hyperglycemia. In these trials, 10% (23/223) of tolvaptan-treated patients discontinued treatment because of an adverse event, compared to 12% (26/220) of placebo-treated patients; no adverse reaction resulting in discontinuation of trial medication occurred at an incidence of >1% in tolvaptan-treated patients. 1 lists the adverse reactions reported in tolvaptan-treated patients with hyponatremia (serum sodium <135 mEq/L) and at a rate at least 2% greater than placebo-treated patients in two 30-day, double-blind, placebo-controlled trials. In these studies, 223 patients were exposed to tolvaptan (starting dose 15 mg, titrated to 30 and 60 mg as needed to raise serum sodium). Adverse events resulting in death in these trials were 6% in tolvaptan-treated patients and 6% in placebo-treated patients. Table 1. Adverse Reactions (>2% more than placebo) in Tolvaptan-Treated Patients in Double-Blind, Placebo-Controlled Hyponatremia Trials System Organ Class MedDRA Preferred Term Tolvaptan 15 mg/day to 60 mg/day (N = 223) n (%) Placebo (N = 220) n (%) Gastrointestinal Disorders Dry mouth 28 (13) 9 (4) Constipation 16 (7) 4 (2) Ge neral Disorders and Administration Site Conditions Thirst * 35 (16) 11 (5) Asthenia 19 (9) 9 (4) Pyrexia 9 (4) 2 (1) Metabolism and Nutrition Disorders Hyperglycemia † 14 (6) 2 (1) Anorexia ‡ 8 (4) 2 (1) Renal and Urinary Disorders Pollakiuria or polyuria § 25 (11) 7 (3) The following terms are subsumed under the referenced ADR in Table 1: * polydipsia, † diabetes mellitus, ‡ decreased appetite, § urine output increased, micturition urgency, nocturia In a subgroup of patients with hyponatremia (N = 475, serum sodium <135 mEq/L) enrolled in a double-blind, placebo-controlled trial (mean duration of treatment was 9 months) of patients with worsening heart failure, the following adverse reactions occurred in tolvaptan-treated patients at a rate at least 2% greater than placebo: mortality (42% tolvaptan, 38% placebo), nausea (21% tolvaptan, 16% placebo), thirst (12% tolvaptan, 2% placebo), dry mouth (7% t…