Niacin

Therapy with lipid-altering agents should be only one component of multiple risk factor intervention in individuals at significantly increased risk for atherosclerotic vascular disease due to hyperlipidemia. Niacin therapy is indicated as an adjunct to diet when the response to a diet restricted in saturated fat and cholesterol and other nonpharmacologic measures alone has been inadequate. Niacin extended-release tablets are indicated to reduce elevated TC, LDL-C, Apo B and TG levels, and to increase HDL-C in patients with primary hyperlipidemia and mixed dyslipidemia. In patients with a history of myocardial infarction and hyperlipidemia, niacin is indicated to reduce the risk of recurrent nonfatal myocardial infarction. In patients with a history of coronary artery disease (CAD) and hyperlipidemia, niacin, in combination with a bile acid binding resin, is indicated to slow progression or promote regression of atherosclerotic disease. Niacin extended-release tablets in combination with a bile acid binding resin is indicated to reduce elevated TC and LDL-C levels in adult patients with primary hyperlipidemia. Niacin is also indicated as adjunctive therapy for treatment of adult patients with severe hypertriglyceridemia who present a risk of pancreatitis and who do not respond adequately to a determined dietary effort to control them. Limitations of Use Addition of niacin extended-release tablets did not reduce cardiovascular morbidity or mortality among patients treated with simvastatin in a large, randomized controlled trial (AIM-HIGH) [see Warnings and Precautions ( 5.1 )] . Niacin extended-release tablets contain­ extended-release niacin (nicotinic acid), and are indicated: To reduce elevated TC, LDL-C, Apo B and TG, and to increase HDL-C in patients with primary hyperlipidemia and mixed dyslipidemia. ( 1 ) To reduce the risk of recurrent nonfatal myocardial infarction in patients with a history of myocardial infarction and hyperlipidemia. ( 1 ) In combination with a bile acid binding resin: Slows progression or promotes regression of atherosclerotic disease in patients with a history of coronary artery disease (CAD) and hyperlipidemia. ( 1 ) As an adjunct to diet to reduce elevated TC and LDL-C in adult patients with primary hyperlipidemia. ( 1 ) To reduce TG in adult patients with severe hypertriglyceridemia. ( 1 ) Limitations of use: Addition of niacin extended-release tablets did not reduce cardiovascular morbidity or mortality among patients treated with simvastatin in a large, randomized controlled trial. ( 5.1 )

500 mg unscored, red, round, film-coated, convex tablet debossed with “KU” on one side, “320” on the other side. 1000 mg unscored, red, oval, film-coated, convex tablet debossed with “KU” on one side, “322” on the other side. Unscored film-coated tablets for oral administration: 500 and 1000 mg niacin extended-release. ( 3 )

Niacin extended-release tablets are contraindicated in the following conditions: Active liver disease or unexplained persistent elevations in hepatic transaminases [see Warnings and Precautions ( 5.3 )] Patients with active peptic ulcer disease Patients with arterial bleeding Hypersensitivity to niacin or any component of this medication [see Adverse Reactions ( 6.1 )] Active liver disease, which may include unexplained persistent elevations in hepatic transaminase levels ( 4 , 5.3 ) Active peptic ulcer disease. ( 4 ) Arterial bleeding. ( 4 ) Known hypersensitivity to product components. ( 4 , 6.1 )

Niacin extended-release tablets preparations should not be substituted for equivalent doses of immediate-release (crystalline) niacin. For patients switching from immediate-release niacin to niacin extended-release tablets, therapy with niacin extended-release tablets should be initiated with low doses (i.e., 500 mg at bedtime) and the niacin extended-release tablets dose should then be titrated to the desired therapeutic response [see Dosage and Administration ( 2.1 )] . Caution should also be used when niacin extended-release tablets are used in patients with unstable angina or in the acute phase of an MI, particularly when such patients are also receiving vasoactive drugs such as nitrates, calcium channel blockers, or adrenergic blocking agents. Niacin is rapidly metabolized by the liver, and excreted through the kidneys. Niacin extended-release tablets are contraindicated in patients with significant or unexplained hepatic impairment [see Contraindications ( 4 ) and Warnings and Precautions ( 5.3 )] and should be used with caution in patients with renal impairment. Patients with a past history of jaundice, hepatobiliary disease, or peptic ulcer should be observed closely during niacin extended-release tablets therapy. Severe hepatic toxicity has occurred in patients substituting sustained-release niacin for immediate-release niacin at equivalent doses. ( 5.3 ) Myopathy has been reported in patients taking niacin extended-release tablets. The risk for myopathy and rhabdomyolysis are increased among elderly patients; patients with diabetes, renal failure, or uncontrolled hypothyroidism; and patients being treated with a statin. ( 5.2 ) Liver enzyme abnormalities and monitoring: Persistent elevations in hepatic transaminase can occur. Monitor liver enzymes before and during treatment. ( 5.3 ) Use with caution in patients with unstable angina or in the acute phase of an MI. ( 5 ) Niacin extended-release tablets can increase serum glucose levels. Glucose levels should be closely monitored in diabetic or potentially diabetic patients particularly during the first few months of use or dose adjustment. ( 5.4 )

5.1 Mortality and Coronary Heart Disease Morbidity Niacin extended-release tablets have not been shown to reduce cardiovascular morbidity or mortality among patients already treated with a statin. The Atherothrombosis Intervention in Metabolic Syndrome with Low HDL/High Triglycerides: Impact on Global Health Outcomes (AIM-HIGH) trial was a randomized placebo-controlled trial of 3414 patients with stable, previously diagnosed cardiovascular disease. Mean baseline lipid levels were LDL-C 74 mg/dL, HDL-C 35 mg/dL, non-HDL-C 111 mg/dL and median triglyceride level of 163-177 mg/dL. Ninety-four percent of patients were on background statin therapy prior to entering the trial. All participants received simvastatin, 40 to 80 mg per day, plus ezetimibe 10 mg per day if needed, to maintain an LDL-C level of 40-80 mg/dL, and were randomized to receive niacin extended-release tablets 1500-2000 mg/day (n=1718) or matching placebo (IR Niacin, 100-150 mg, n=1696). On-treatment lipid changes at two years for LDL-C were -12.0% for the simvastatin plus niacin extended-release tablets group and -5.5% for the simvastatin plus placebo group. HDL-C increased by 25.0% to 42 mg/dL in the simvastatin plus niacin extended-release tablets group and by 9.8% to 38 mg/dL in the simvastatin plus placebo group (P<0.001). Triglyceride levels decreased by 28.6% in the simvastatin plus niacin extended-release tablets group and by 8.1% in the simvastatin plus placebo group. The primary outcome was an ITT composite of the first study occurrence of coronary heart disease death, nonfatal myocardial infarction, ischemic stroke, hospitalization for acute coronary syndrome or symptom-driven coronary or cerebral revascularization procedures. The trial was stopped after a mean follow-up period of 3 years owing to a lack of efficacy. The primary outcome occurred in 282 patients in the simvastatin plus niacin extended-release tablets group (16.4%) and in 274 patients in the simvastatin plus placebo group (16.2%) (HR 1.02 [95% CI, 0.87-1.21], P=0.79. In an ITT analysis, there were 42 cases of first occurrence of ischemic stroke reported, 27 (1.6%) in the simvastatin plus niacin extended-release tablets group and 15 (0.9%) in the simvastatin plus placebo group, a non-statistically significant result (HR 1.79, [95%CI = 0.95-3.36], p=0.071). The on-treatment ischemic stroke events were 19 for the simvastatin plus niacin extended-release tablets group and 15 for the simvastatin plus placebo group [see Adverse Reactions ( 6.1 )] .

5.2 Skeletal Muscle Cases of rhabdomyolysis have been associated with concomitant administration of lipid-altering doses (≥ 1 g/day) of niacin and statins. Elderly patients and patients with diabetes, renal failure, or uncontrolled hypothyroidism are particularly at risk. Monitor patients for any signs and symptoms of muscle pain, tenderness, or weakness, particularly during the initial months of therapy and during any periods of upward dosage titration. Periodic serum creatine phosphokinase (CPK) and potassium determinations should be considered in such situations, but there is no assurance that such monitoring will prevent the occurrence of severe myopathy.

5.3 Liver Dysfunction Cases of severe hepatic toxicity, including fulminant hepatic necrosis, have occurred in patients who have substituted sustained-release (modified-release, timed-release) niacin products for immediate-release (crystalline) niacin at equivalent doses. Niacin extended-release tablets should be used with caution in patients who consume substantial quantities of alcohol and/or have a past history of liver disease. Active liver diseases or unexplained transaminase elevations are contraindications to the use of niacin extended-release tablets. Niacin preparations have been associated with abnormal liver tests. In three placebo-controlled clinical trials involving titration to final daily niacin extended-release tablets doses ranging from 500 to 3000 mg, 245 patients received niacin extended-release tablets for a mean duration of 17 weeks. No patient with normal serum transaminase levels (AST, ALT) at baseline experienced elevations to more than 3 times the upper limit of normal (ULN) during treatment with niacin extended-release tablets. In these studies, fewer than 1% (2/245) of niacin extended-release tablets patients discontinued due to transaminase elevations greater than 2 times the ULN. Liver-related tests should be performed on all patients during therapy with niacin extended-release tablets. Serum transaminase levels, including AST and ALT (SGOT and SGPT), should be monitored before treatment begins, every 6 to 12 weeks for the first year, and periodically thereafter (e.g., at approximately 6-month intervals). Special attention should be paid to patients who develop elevated serum transaminase levels, and in these patients, measurements should be repeated promptly and then performed more frequently. If the transaminase levels show evidence of progression, particularly if they rise to 3 times ULN and are persistent, or if they are associated with symptoms of nausea, fever, and/or malaise, the drug should be discontinued.

5.4 Laboratory Abnormalities Increase in Blood Glucose: Niacin treatment can increase fasting blood glucose. Frequent monitoring of blood glucose should be performed to ascertain that the drug is producing no adverse effects. Diabetic patients may experience a dose-related increase in glucose intolerance. Diabetic or potentially diabetic patients should be observed closely during treatment with niacin extended-release tablets, particularly during the first few months of use or dose adjustment; adjustment of diet and/or hypoglycemic therapy may be necessary. […]

The following adverse reactions are discussed in greater detail in other sections of the labeling: Mortality and Coronary Heart Disease Morbidity [see Warnings and Precautions ( 5.1 ) ] Skeletal Muscle (rhabdomyolysis) [see Warnings and Precautions ( 5.2 ) ] Liver Dysfunction [see Warnings and Precautions ( 5.3 ) ] Laboratory Abnormalities [see Warnings and Precautions ( 5.4 ) ] Most common adverse reactions (incidence >5% and greater than placebo) are flushing, diarrhea, nausea, vomiting, increased cough, and pruritus. ( 6.1 ) Flushing of the skin may be reduced in frequency or severity by pretreatment with aspirin (up to the recommended dose of 325 mg taken 30 minutes prior to niacin extended-release tablets dose). ( 2.2 ) To report SUSPECTED ADVERSE REACTIONS, contact Quagen Pharmaceuticals LLC at 1- 888-344-9603 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. In the placebo-controlled clinical trials database of 402 patients (age range 21-75 years, 33% women, 89% Caucasians, 7% Blacks, 3% Hispanics, 1% Asians) with a median treatment duration of 16 weeks, 16% of patients on niacin extended-release tablets and 4% of patients on placebo discontinued due to adverse reactions. The most common adverse reactions in the group of patients treated with niacin extended-release tablets that led to treatment discontinuation and occurred at a rate greater than placebo were flushing (6% vs. 0%), rash (2% vs. 0%), diarrhea (2% vs. 0%), nausea (1% vs. 0%), and vomiting (1% vs. 0%). The most commonly reported adverse reactions (incidence >5% and greater than placebo) in the niacin extended-release tablets controlled clinical trial database of 402 patients were flushing, diarrhea, nausea, vomiting, increased cough and pruritus. In the placebo-controlled clinical trials, flushing episodes (i.e., warmth, redness, itching and/or tingling) were the most common treatment-emergent adverse reactions (reported by as many as 88% of patients) for niacin extended-release tablets. Spontaneous reports suggest that flushing may also be accompanied by symptoms of dizziness, tachycardia, palpitations, shortness of breath, sweating, burning sensation/skin burning sensation, chills, and/or edema, which in rare cases may lead to syncope. In pivotal studies, 6% (14/245) of niacin extended-release tablets patients discontinued due to flushing. In comparisons of immediate-release (IR) niacin and niacin extended-release tablets, although the proportion of patients who flushed was similar, fewer flushing episodes were reported by patients who received niacin extended-release tablets. Following 4 weeks of maintenance therapy at daily doses of 1500 mg, the incidence of flushing over the 4-week period averaged 8.6 events per patient for IR niacin versus 1.9 following niacin extended-release tablets. Other adverse reactions occurring in 5% of patients treated with niacin extended-release tablets and at an incidence greater than placebo are shown in Table 2 below. Table 2. Treatment-Emergent Adverse Reactions by Dose Level in 5% of Patients and at an Incidence Greater than Placebo; Regardless of Causality Assessment in Placebo-Controlled Clinical Trials Placebo-Controlled Studies Niacin Extended-release Tablets Treatment Pooled results from placebo-controlled studies; for niacin extended-release tablets, n=245 and median treatment duration=16 weeks. Number of niacin extended-release tablets patients (n) are not additive across doses. Recommended Daily Maintenance Doses Adverse reactions are reported at the initial dose where they occur. Placebo (n = 157) % 500 mg The 500 mg/day dose is outside the recommended daily maintenance dosing range [see Dosage and Administration (2.2)]. (n = 87) % 1,000 mg (n = 110) % 1,500 mg (n = 136) % 2,000 mg (n = 95) % Gastrointestinal Disorders Diarrhea 13 7 10 10 14 Nausea 7 5 6 4 11 Vomiting 4 0 2 4 9 Respiratory Cough, Increased 6 3 2 < 2 8 Skin and Subcutaneous Tissue Disorders Pruritus 2 8 0 3 0 Rash 0 5 5 5 0 Vascular Disorders Flushing 10 patients discontinued before receiving 500 mg, therefore they were not included. 19 68 69 63 55 Note: Percentages are calculated from the total number of patients in each column. In general, the incidence of adverse events was higher in women compared to men. Atherothrombosis Intervention in Metabolic Syndrome with Low HDL/High Triglycerides: Impact on Global Health Outcomes (AIM-HIGH) In AIM-HIGH involving 3414 patients (mean age of 64 years, 15% women, 92% Caucasians, 34% with diabetes mellitus) with stable, previously diagnosed cardiovascular disease, all patients received simvastatin, 40 to 80 mg per day, plus ezetimibe 10 mg per day if needed, to maintain an LDL-C level of 40-80 mg/dL, and were randomized to receive niacin extended-release tablets 1500-2000 mg/day (n=1718) or matching placebo (IR Niacin, 100-150 mg, n=1696). The incidence of the adverse reactions of “blood glucose increased” (6.4% vs. 4.5%) and “diabetes mellitus” (3.6% vs. 2.2%) was significantly higher in the simvastatin plus niacin extended-release tablets group as compared to the simvastatin plus placebo group. There were 5 cases of rhabdomyolysis reported, 4 (0.2%) in the simvastatin plus niacin extended-release tablets group and one (<0.1%) in the simvastatin plus placebo group.

6.2 Postmarketing Experience The following additional adverse reactions have been identified during post-approval use of niacin extended-release tablets. Because the below reactions are reported voluntarily from a population of uncertain size, it is generally not possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Cardiac disorders: tachycardia, palpitations, atrial fibrillation, other cardiac arrhythmias Eye disorders: blurred vision, macular edema Gastrointestinal disorders: peptic ulcers, eructation, flatulence Hepatobiliary disorders: hepatitis, jaundice Immune system disorders: hypersensitivity reactions (including anaphylaxis, angioedema, urticaria, flushing, dyspnea, tongue edema, larynx edema, face edema, peripheral edema, laryngismus, and vesiculobullous rash) Metabolism and nutrition disorders: decreased glucose tolerance, gout Musculoskeletal and connective tissue disorders: myalgia, myopathy Nervous system disorders: dizziness, insomnia, asthenia, nervousness, paresthesia, migraine Respiratory, thoracic and mediastinal disorders: dyspnea Skin and subcutaneous tissue disorders: maculopapular rash, dry skin, sweating, burning sensation/skin burning sensation, skin discoloration, acanthosis nigricans Vascular disorders: syncope, hypotension, postural hypotension Clinical Laboratory Abnormalities Chemistry: Elevations in serum transaminases, LDH, fasting glucose, uric acid, total bilirubin, amylase and creatine kinase, and reduction in phosphorus. Hematology: Slight reductions in platelet counts and prolongation in prothrombin time.

Statins: Caution should be used when prescribing niacin with statins as these agents can increase risk of myopathy/rhabdomyolysis. ( 5.2 , 7.1 ) Bile Acid Sequestrants: Bile acid sequestrants have a high niacin-binding capacity and should be taken at least 4 to 6 hours before niacin extended-release administration. ( 7.2 )

7.1 Statins Caution should be used when prescribing niacin (≥1 gm/day) with statins as these drugs can increase risk of myopathy/rhabdomyolysis [see Warnings and Precautions ( 5 ) and Clinical Pharmacology ( 12.3 )] .

7.2 Bile Acid Sequestrants An in vitro study results suggest that the bile acid-binding resins have high niacin binding capacity. Therefore, 4 to 6 hours, or as great an interval as possible, should elapse between the ingestion of bile acid-binding resins and the administration of niacin extended-release tablets [see Clinical Pharmacology ( 12.3 )] .

7.3 Aspirin Concomitant aspirin may decrease the metabolic clearance of nicotinic acid. The clinical relevance of this finding is unclear.

7.4 Antihypertensive Therapy Niacin may potentiate the effects of ganglionic blocking agents and vasoactive drugs resulting in postural hypotension.

7.5 Other Vitamins or other nutritional supplements containing large doses of niacin or related compounds such as nicotinamide may potentiate the adverse effects of niacin extended-release.

7.6 Laboratory Test Interactions Niacin may produce false elevations in some fluorometric determinations of plasma or urinary catecholamines. Niacin may also give false-positive reactions with cupric sulfate solution (Benedict’s reagent) in urine glucose tests.

Pregnancy: Discontinue in patients with hyperlipidemia; assess individual risks and benefits in patients with hypertriglyceridemia. ( 8.1 ) Lactation: Advise patients not to breastfeed during treatment. ( 8.2 ) Renal impairment: Niacin extended-release should be used with caution in patients with renal impairment. ( 5 , 8.6 ) Hepatic impairment: Niacin extended-release is contraindicated in active liver disease or significant or unexplained hepatic dysfunction or unexplained elevations of serum transaminases. ( 4 , 5 , 5.3 , 8.7 )

8.1 Pregnancy Risk Summary Discontinue niacin extended-release tablets when pregnancy is recognized in patients receiving the drug for the treatment of hyperlipidemia. Assess the individual risks and benefits of continuing niacin extended-release tablets during pregnancy in patients receiving the drug for the treatment of hypertriglyceridemia. Advise patients to inform their healthcare provider of a known or suspected pregnancy. The potential for embryofetal toxicity with the doses of niacin in niacin extended-release tablets is unknown. The available data on niacin extended-release tablets use in pregnant women are insufficient to evaluate for a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes. Animal reproduction studies have not been conducted with niacin or with niacin extended-release tablets. Treatment of hypercholesterolemia is not generally necessary during pregnancy. Atherosclerosis is a chronic process and the discontinuation of lipid-lowering drugs during pregnancy should have little impact on the outcome of long-term therapy of primary hypercholesterolemia for most patients. The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively.

8.2 Lactation Risk Summary Niacin is present in human milk and the amount of niacin increases with maternal supplementation. There is no information on the effects of the doses of niacin in niacin extended-release tablets on the breastfed infant or the effects on milk production. Because of the potential for serious adverse reactions in breastfeeding infants, including hepatotoxicity, advise patients not to breastfeed during treatment with niacin extended-release tablets.

8.4 Pediatric Use Safety and effectiveness of niacin therapy in pediatric patients (≤16 years) have not been established.

8.5 Geriatric Use Of 979 patients in clinical studies of niacin extended-release tablets, 21% of the patients were age 65 and over. No overall differences in safety and effectiveness were observed between these patients and younger patients, and other reported clinical experience has not identified differences in responses between the elderly and younger patients, but greater sensitivity of some older individuals cannot be ruled out.

8.6 Renal Impairment No studies have been performed in this population. Niacin extended-release tablets should be used with caution in patients with renal impairment [see Warnings and Precautions ( 5 )] .

8.7 Hepatic Impairment No studies have been performed in this population. Niacin extended-release tablets should be used with caution in patients with a past history of liver disease and/or who consume substantial quantities of alcohol. Active liver disease, unexplained transaminase elevations and significant or unexplained hepatic dysfunction are contraindications to the use of niacin extended-release tablets [see Contraindications ( 4 ) and Warnings and Precautions ( 5.3 )] .

8.8 Gender Data from the clinical trials suggest that women have a greater hypolipidemic response than men at equivalent doses of niacin extended-release tablets.

8.8 Gender Data from the clinical trials suggest that women have a greater hypolipidemic response than men at equivalent doses of niacin extended-release tablets.

The mechanism by which niacin alters lipid profiles has not been well defined. It may involve several actions including partial inhibition of release of free fatty acids from adipose tissue, and increased lipoprotein lipase activity, which may increase the rate of chylomicron triglyceride removal from plasma. Niacin decreases the rate of hepatic synthesis of VLDL and LDL, and does not appear to affect fecal excretion of fats, sterols, or bile acids.