NIASPAN® (niacin extended-release tablets), contain niacin, a B-complex vitamin and antihyperlipidemic agent. Niacin (nicotinic acid, or 3-pyridinecarboxylic acid) is a white, crystalline powder, very soluble in water, with the following structural formula:

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NIASPAN® is an unscored, off-white tablet for oral administration that contains no color additives and is available in three tablet strengths containing 500, 750, and 1000mg niacin. NIASPAN tablets also contain the inactive ingredients methylcellulose, povidone, and stearic acid.

Niacin functions in the body after conversion to nicotinamide adenine dinucleotide (NAD) in the NAD coenzyme system. Niacin (but not nicotinamide) in gram doses reduces total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and triglycerides (TG), and increases high-density lipoprotein cholesterol (HDL-C). The magnitude of the individual lipid and lipoprotein responses may be influenced by the severity and type of underlying lipid abnormality. The increase in total HDL-C is associated with an increase in apolipoprotein A-I (Apo A-I) and a shift in the distribution of HDL subfractions. These shifts include an increase in the HDL 2 :HDL 3 ratio, and an elevation in lipoprotein A-I (Lp A-I, an HDL particle containing only Apo A-I). Niacin treatment also decreases serum levels of apolipoprotein B-100 (Apo B), the major protein component of the very low-density lipoprotein (VLDL) and LDL fractions, and of Lp(a), a variant form of LDL independently associated with coronary risk. 1 In addition, preliminary reports suggest that niacin causes favorable LDL particle size transformations, although the clinical relevance of this effect requires further investigation. The effect of niacin-induced changes in lipids/lipoproteins on cardiovascular morbidity or mortality in individuals without pre-existing coronary disease has not been established.

A variety of clinical studies have demonstrated that elevated levels of TC, LDL-C, and Apo B promote human atherosclerosis. Similarly, decreased levels of HDL-C are associated with the development of atherosclerosis. Epidemiological investigations have established that cardiovascular morbidity and mortality vary directly with the level of TC and LDL-C, and inversely with the level of HDL-C.

Like LDL, cholesterol-enriched triglyceride-rich lipoproteins, including VLDL, intermediate density lipoprotein (IDL), and remnants, can also promote atherosclerosis. Elevated plasma TG are frequently found in a triad with low HDL-C levels and small LDL particles, as well as in association with non-lipid metabolic risk factors for coronary heart disease (CHD). As such total plasma TG has not consistently been shown to be an independent risk factor for CHD. Furthermore, the independent effect of raising HDL-C or lowering TG on the risk of coronary and cardiovascular morbidity and mortality has not been determined.

Mechanism of Action

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.

/Metabolism

Absorption

Niacin is rapidly and extensively absorbed (at least 60 to 76% of dose) when administered orally. To maximize bioavailability and reduce the risk of gastrointestinal (GI) upset, administration of NIASPAN with a low-fat meal or snack is recommended.

Single-dose bioavailability studies have demonstrated that NIASPAN tablet strengths are not interchangeable.

Distribution

Studies using radiolabeled niacin in mice show that niacin and its metabolites concentrate in the liver, kidney and adipose tissue.

Metabolism

The pharmacokinetic profile of niacin is complicated due to rapid and extensive first-pass metabolism, which is species and dose-rate specific. In humans, one pathway is through a simple conjugation step with glycine to form nicotinuric acid (NUA). NUA is then excreted in the urine, although there may be a small amount of reversible metabolism back to niacin. The other pathway results in the formation of nicotinamide adenine dinucleotide (NAD). It is unclear whether nicotinamide is formed as a precursor to, or following the synthesis of, NAD. Nicotinamide is further metabolized to at least N-methylnicotinamide (MNA) and nicotinamide-N-oxide (NNO). MNA is further metabolized to two other compounds, N-methyl-2-pyridone-5-carboxamide (2PY) and N-methyl-4-pyridone-5-carboxamide (4PY). The formation of 2PY appears to predominate over 4PY in humans. At the doses used to treat hyperlipidemia, these metabolic pathways are saturable, which explains the nonlinear relationship between niacin dose and plasma concentrations following multiple-dose NIASPAN administration (Table 1).

Nicotinamide does not have hypolipidemic activity; the activity of the other metabolites is unknown.

Table 1.  Mean Steady-State Pharmacokinetic Parameters for Plasma Niacin
NIASPAN Niacin
dose/day given as Peak
Concentration
(µg/mL)
Time to Peak
(hrs)
1000mg 2 × 500mg 0.6 5
1500mg 2 × 750mg 4.9 4
2000mg 2 × 1000mg 15.5 5

Elimination

Niacin and its metabolites are rapidly eliminated in the urine. Following single and multiple doses, approximately 60 to 76% of the niacin dose administered as NIASPAN was recovered in urine as niacin and metabolites; up to 12% was recovered as unchanged niacin after multiple dosing. The ratio of metabolites recovered in the urine was dependent on the dose administered.

Special Populations

Hepatic

No studies have been performed. NIASPAN should be used with caution in patients with a past history of liver disease, who consume substantial quantities of alcohol, or have unexplained transaminase elevations. NIASPAN is contraindicated in patients with active liver disease (see ).

Renal

There are no data in this population. NIASPAN should be used with caution in patients with renal disease (see PRECAUTIONS ).

Gender

Steady-state plasma concentrations of niacin and metabolites after administration of NIASPAN are generally higher in women than in men, with the magnitude of the difference varying with dose and metabolite. Recovery of niacin and metabolites in urine, however, is generally similar for men and women, indicating that absorption is similar for both genders. The gender differences observed in plasma levels of niacin and its metabolites may be due to gender-specific differences in metabolic rate or volume of distribution. Data from the clinical trials suggest that women have a greater hypolipidemic response than men at equivalent doses of NIASPAN.

Niacin Clinical Studies

The role of LDL-C in atherogenesis is supported by pathological observations, clinical studies, and many animal experiments. Observational epidemiological studies have clearly established that high TC or LDL-C and low HDL-C are risk factors for CHD. Additionally, elevated levels of Lp(a) have been shown to be independently associated with CHD risk. 1 The efficacy of niacin in improving lipoprotein lipid profiles, either alone or in combination with other lipid-altering drugs, as an adjunct to diet therapy in the treatment of hyperlipoproteinemia has been well documented.

Niacin' ability to reduce mortality and the risk of definite, nonfatal myocardial infarction (MI) has also been assessed in long-term studies. The Coronary Drug Project, 2 completed in 1975, was designed to assess the safety and efficacy of niacin and other lipid-altering drugs in men 30 to 64 years old with a history of MI. Over an observation period of 5 years, niacin treatment was associated with a statistically significant reduction in nonfatal, recurrent MI. The incidence of definite, nonfatal MI was 8.9% for the 1,119 patients randomized to nicotinic acid versus 12.2% for the 2,789 patients who received placebo ( p <0.004). Total mortality was similar in the two groups at 5 years (24.4% with nicotinic acid versus 25.4% with placebo; p =N.S.). At the time of a 15 year follow-up, there were 11% (69) fewer deaths in the niacin group compared to the placebo cohort (52.0% versus 58.2%; p =0.0004). 3 However, mortality at 15 years was not an original endpoint of the Coronary Drug Project. In addition, patients had not received niacin for approximately 9 years, and confounding variables such as concomitant medication use and medical or surgical treatments were not controlled.

The Cholesterol-Lowering Atherosclerosis Study (CLAS) was a randomized, placebo-controlled, angiographic trial testing combined colestipol and niacin therapy in 162 non-smoking males with previous coronary bypass surgery. 4 The primary, per-subject cardiac endpoint was global coronary artery change score. After 2 years, 61% of patients in the placebo cohort showed disease progression by global change score (n=82), compared with only 38.8% of drug-treated subjects (n=80), when both native arteries and grafts were considered ( p <0.005); disease regression also occurred more frequently in the drug-treated group (16.2% versus 2.4%; p =0.002). In a follow-up to this trial in a subgroup of 103 patients treated for 4 years, again, significantly fewer patients in the drug-treated group demonstrated progression than in the placebo cohort (48% versus 85%, respectively; p <0.0001). 5

The Familial Atherosclerosis Treatment Study (FATS) in 146 men ages 62 and younger with Apo B levels >/=125 mg/dL, established coronary artery disease, and family histories of vascular disease, assessed change in severity of disease in the proximal coronary arteries by quantitative arteriography. 6 Patients were given dietary counseling and randomized to treatment with either conventional therapy with double placebo (or placebo plus colestipol if the LDL-C was elevated); lovastatin plus colestipol; or niacin plus colestipol. In the conventional therapy group, 46% of patients had disease progression (and no regression) in at least one of nine proximal coronary segments; regression was the only change in 11%. In contrast, progression (as the only change) was seen in only 25% in the niacin plus colestipol group, while regression was observed in 39%. Though not an original endpoint of the trial, clinical events (death, MI, or revascularization for worsening angina) occurred in 10 of 52 patients who received conventional therapy, compared with 2 of 48 who received niacin plus colestipol.

The Harvard Atherosclerosis Reversibility Project (HARP) was a randomized placebo-controlled, 2.5-year study of the effect of a stepped-care antihyperlipidemic drug regimen on 91 patients (80 men and 11 women) with CHD and average baseline TC levels less than 250mg/dL and ratios of TC to HDL-C greater than 4.0. 7 Drug treatment consisted of an HMG-CoA reductase inhibitor administered alone as initial therapy followed by addition of varying dosages of either a slow-release nicotinic acid, cholestyramine, or gemfibrozil. Addition of nicotinic acid to the HMG-CoA reductase inhibitor resulted in further statistically significant mean reductions in TC, LDL-C, and TG, as well as a further increase in HDL-C in a majority of patients (40 of 44 patients). The ratios of TC to HDL-C and LDL-C to HDL-C were also significantly reduced by this combination drug regimen (see , Skeletal Muscle ).

NIASPAN Clinical Studies

Placebo-controlled Clinical Studies in Patients with Primary Hypercholesterolemia and Mixed Dyslipidemia:   In two randomized, double-blind, parallel, multi-center, placebo-controlled trials, NIASPAN dosed at 1000, 1500 or 2000mg daily at bedtime with a low-fat snack for 16 weeks (including 4 weeks of dose escalation) favorably altered lipid profiles compared to placebo (Table 2). Women appeared to have a greater response than men at each NIASPAN dose level (see Gender Effect , below).

Table 2.  Lipid Response to NIASPAN Therapy
 
  Mean Percent Change from Baseline to Week 16 *
n TC LDL-C HDL-C TC/HDL-C TG Lp(a) Apo B Apo A-1
NIASPAN 1000mg qhs
41 -3 -5 +18 -17 -21 -13 -6 +9
NIASPAN 2000mg qhs
41 -10 -14 +22 -25 -28 -27 -16 +8
40 0 -1 +4 -3 0 0 +1 +3
NIASPAN 1500mg qhs
76 -8 -12 +20 -20 -13 -15 -12 +8
73 +2 +1 +2 +1 +12 +2 +1 +2
n = number of patients at baseline;
* Mean percent change from baseline for all NIASPAN doses was significantly different ( p <0.05) from placebo for all lipid parameters shown except Apo A-1 at 2000mg.

In a double-blind, multi-center, forced dose-escalation study, monthly 500mg increases in NIASPAN dose resulted in incremental reductions of approximately 5% in LDL-C and Apo B levels in the daily dose range of 500mg through 2000mg (Table 3). Women again tended to have a greater response to NIASPAN than men (see Gender Effect , below).

Table 3.  Lipid Response in Dose-Escalation Study
  Mean Percent Change from Baseline *
 
n TC LDL-C HDL-C TC/HDL-C TG Lp(a) Apo B Apo A-1
44 -2 -1 +5 -7 -6 -5 -2 +4
NIASPAN
87  
  500mg qhs
  -2 -3 +10 -10 -5 -3 -2 +5
  1000mg qhs
-5 -9 +15 -17 -11 -12 -7 +8
  1500mg qhs
-11 -14 +22 -26 -28 -20 -15 +10
  2000mg qhs
-12 -17 +26 -29 -35 -24 -16 +12
n = number of patients enrolled;
& Placebo data shown are after 24 weeks of placebo treatment.
* For all NIASPAN doses except 500mg, mean percent change from baseline was significantly different ( p <0.05) from placebo for all lipid parameters shown except Lp(a) and Apo A-1 which were significantly different from placebo starting with 1500mg and 2000mg, respectively.

Pooled results for major lipids from these three placebo-controlled studies are shown below (Table 4).

Table 4.  Selected Lipid Response to NIASPAN in Placebo-controlled Clinical Studies *
 
  Mean Baseline and Median Percent Change from Baseline (25 th , 75 th Percentiles)
 NIASPAN
Dose
n LDL-C HDL-C TG
1000mg qhs
104  
 Baseline (mg/dL)
  218 45 172
  Percent Change
-7 (-15, 0) +14 (+7,+23) -16 (-34,+3)
1500mg qhs
120  
 Baseline (mg/dL)
   212 46 171
  Percent Change
-13 (-21,-4) +19 (+9,+31) -25 (-45,-2)
2000mg qhs
85  
 Baseline (mg/dL)
   220 44 160
  Percent Change
-16 (-26,-7) +22 (+15,+34) -38 (-52,-14)
* Represents pooled analyses of results; minimum duration on therapy at each dose was 4 weeks.

Gender Effect:   Combined data from the three placebo-controlled NIASPAN studies in patients with primary hypercholesterolemia and mixed dyslipidemia suggest that, at each NIASPAN dose level studied, changes in lipid concentrations are greater for women than for men (Table 5).

Table 5.  Effect of Gender on NIASPAN Dose Response
 
  Mean Percent Change from Baseline
 
  LDL-C HDL-C TG Apo B
 NIASPAN
   Dose
n
(M/F)
M F M F M F M F
500mg qhs
50/37 -2 -5 +11 +8 -3 -9 -1 -5
1000mg qhs
76/52 -6 * -11 * +14 +20 -10 -20 -5 * -10 *
1500mg qhs
104/59 -12 -16 +19 +24 -17 -28 -13 -15
2000mg qhs
75/53 -15 -18 +23 +26 -30 -36 -16 -16
n = Number of male/female patients enrolled.
* Percent change significantly different between genders (p<0.05).

Long-term Study:    In a recently completed long-term open-label study, patients with primary hypercholesterolemia and mixed dyslipidemia received NIASPAN in doses titrated to individual response and tolerance. An HMG-CoA reductase inhibitor or a bile acid sequestrant (BAS) was added to NIASPAN therapy for patients whose response to NIASPAN alone (usually at 2000mg qhs) was insufficient, or who would not tolerate higher niacin doses. Interim data from 48 and 96 weeks of treatment (Table 6) suggest combination therapy enhanced TC and LDL-C response (see , Skeletal Muscle ).

Table 6.  NIASPAN Efficacy with Combination Therapy
  Mean Percent Change from Baseline
n TC LDL-C HDL-C TC/HDL-C TG Lp(a) * Apo B *
NIASPAN Alone
Baseline
185 - - - - - - -
48 weeks
101 -11 -18 +29 -29 -24 -36 -15
96 weeks
74 -10 -18 +32 -30 -27 na na
NIASPAN & HMG-CoA
Baseline
53 - - - - - - -
48 weeks
45 -23 -32 +26 -38 -30 -19 -26
96 weeks
37 -24 -32 +25 -38 -32 na na
NIASPAN & BAS
Baseline
16 - - - - - - -
48 weeks
15 -11 -20 +36 -33 -13 -24 -19
96 weeks
7 -15 -28 +31 -34 +5 na na
Note: Median NIASPAN dose was 2000mg qhs in each dose group. Mean duration of HMG-CoA combination therapy was approximately 47 weeks. Mean duration of BAS combination therapy was approximately 40 weeks.
* number of patients (n) are up to 33% lower at baseline and at 48 weeks; na = data are not available.

Other Patient Populations:    In a double-blind, multi-center, 19-week study the lipid-altering effects of NIASPAN (forced titration to 2000mg qhs) were compared to baseline in patients whose primary lipid abnormality was a low level of HDL-C (HDL-C</=40 mg/dL, TG </=400 mg/dL, and LDL-C</=160, or <130 mg/dL in the presence of CHD). Results are shown below (Table 7).

Table 7.  Lipid Response to NIASPAN in Patients with Low HDL-C
 
  Mean Baseline and Mean Percent Change from Baseline
 
n TC LDL-C HDL-C TC/HDL-C TG Lp(a) # Apo B # Apo A-I # Lp A-I &
Baseline
(mg/dL)
88 190 120 31 6 194 8 106 105 32
Week 19
(% Change)
71 -3 0 +26 -22 -30 -20 -9 +11 +20
n = number of patients enrolled
* Mean percent change from baseline was significantly different (p<0.05) for all lipid parameters shown except LDL-C.
# n=72 at baseline and 69 at week 19.
& n=30 at baseline and week 19.

At NIASPAN 2000 mg/day, median changes from baseline (25 th , 75 th percentiles) for LDL-C, HDL-C, and TG were -3% (-14, + 12%), +27% (+13, +38%), and -33% (-50, -19%), respectively.

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 hypercholesterolemia. 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 (see also the NCEP treatment guidelines 8 ). Prior to initiating therapy with niacin, secondary causes for hypercholesterolemia (e.g., poorly controlled diabetes mellitus, hypothyroidism, nephrotic syndrome, dysproteinemias, obstructive liver disease, other drug therapy, alcoholism) should be excluded, and a lipid profile obtained to measure TC, HDL-C, and TG.

  1. NIASPAN is indicated as an adjunct to diet for reduction of elevated TC, LDL-C, Apo B and TG levels, and to increase HDL-C in patients with primary hypercholesterolemia (heterozygous familial and nonfamilial) and mixed dyslipidemia (Frederickson Types IIa and IIb; Table 8), when the response to an appropriate diet has been inadequate.
  2. In patients with a history of myocardial infarction and hypercholesterolemia, niacin is indicated to reduce the risk of recurrent nonfatal myocardial infarction.
  3. In patients with a history of coronary artery disease (CAD) and hypercholesterolemia, niacin, in combination with a bile acid binding resin, is indicated to slow progression or promote regression of atherosclerotic disease.
  4. NIASPAN in combination with a bile acid binding resin is indicated as an adjunct to diet for reduction of elevated TC and LDL-C levels in adult patients with primary hypercholesterolemia (Type IIa; Table 8), when the response to an appropriate diet, or diet plus monotherapy, has been inadequate.
  5. Niacin is also indicated as adjunctive therapy for treatment of adult patients with very high serum triglyceride levels (Types IV and V hyperlipidemia; Table 8) who present a risk of pancreatitis and who do not respond adequately to a determined dietary effort to control them. Such patients typically have serum TG levels over 2000 mg/dL and have elevations of VLDL-C as well as fasting chylomicrons (Type V hyperlipidemia; Table 8). Patients who consistently have total serum or plasma TG below 1000 mg/dL are unlikely to develop pancreatitis. Therapy with niacin may be considered for those patients with TG elevations between 1000 and 2000 mg/dL who have a history of pancreatitis or of recurrent abdominal pain typical of pancreatitis. Some Type IV patients with TG under 1000 mg/dL may, through dietary or alcohol indiscretion, convert to a Type V pattern with massive TG elevations accompanying fasting chylomicronemia, but the influence of niacin therapy on risk of pancreatitis in such situations has not been adequately studied. Drug therapy is not indicated for patients with Type I hyperlipoproteinemia, who have elevations of chylomicrons and plasma TG, but who have normal levels of VLDL-C. Inspection of plasma refrigerated for 14 hours is helpful in distinguishing Types I, IV, and V hyperlipoproteinemia. 9

Table 8.  Classification of Hyperlipoproteinemias
Lipid Elevations
Type
Lipoproteins Elevated
Major Minor
I (rare)
chylomicrons
TG up-->TC
IIa
LDL
TC -
IIb
LDL, VLDL
TC TG
III (rare)
IDL
TC/TG -
IV
TG up-->TC
V (rare)
chylomicrons, VLDL
TG up-->TC
TC = total cholesterol; TG = triglycerides; LDL = low-density lipoprotein; VLDL = very low-density lipoprotein; IDL = intermediate-density lipoprotein
up--> = increased or no change

CONTRAINDICATIONS

NIASPAN is contraindicated in patients with a known hypersensitivity to niacin or any component of this medication, significant or unexplained hepatic dysfunction, active peptic ulcer disease, or arterial bleeding.

NIASPAN preparations should not be substituted for equivalent doses of immediate-release (crystalline) niacin. For patients switching from immediate-release niacin to NIASPAN, therapy with NIASPAN should be initiated with low doses (i.e., 500 mg qhs) and the NIASPAN dose should then be titrated to the desired therapeutic response (see DOSAGE AND ADMINISTRATION ).

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.

NIASPAN 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 NIASPAN.

Niacin preparations, like some other lipid-lowering therapies, have been associated with abnormal liver tests. In three placebo-controlled clinical trials involving titration to final daily NIASPAN doses ranging from 500 to 3000mg, 245 patients received NIASPAN 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 NIASPAN. In these studies, fewer than 1% (2/245) of NIASPAN patients discontinued due to transaminase elevations greater than 2 times the ULN.

Interim results from a recently completed, long-term extension study involving more than 700 patients (617 who were treated for a mean duration of 50 weeks) showed that less than 1% (4/717) of NIASPAN-treated patients with normal serum transaminase levels at baseline experienced elevations greater than 3 times ULN (one of the four was receiving concomitant HMG-CoA reductase inhibitor therapy).

In the placebo-controlled clinical trials and the long-term extension study, elevations in transaminases did not appear to be related to treatment duration; elevations in AST levels did appear to be dose related. Transaminase elevations were reversible upon discontinuation of NIASPAN.

Liver tests should be performed on all patients during therapy with NIASPAN. Serum transaminase levels, including AST and ALT (SGOT and SGPT), should be monitored before treatment begins, every 6 weeks 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 the ULN and are persistent, or if they are associated with symptoms of nausea, fever, and/or malaise, the drug should be discontinued.

Skeletal Muscle

Rare cases of rhabdomyolysis have been associated with concomitant administration of lipid-altering doses (>/=1 g/day) of niacin and HMG-CoA reductase inhibitors. However, no cases of rhabdomyolysis have been reported in 124 patients who were treated with NIASPAN in combination with various HMG-CoA reductase inhibitors. Physicians contemplating combined therapy with HMG-CoA reductase inhibitors and NIASPAN should carefully weigh the potential benefits and risks and should carefully 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 of either drug. 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.

PRECAUTIONS

General

Before instituting therapy with NIASPAN, an attempt should be made to control hyperlipidemia with appropriate diet, exercise, and weight reduction in obese patients, and to treat other underlying medical problems (see ).

Patients with a past history of jaundice, hepatobiliary disease, or peptic ulcer should be observed closely during NIASPAN therapy. Frequent monitoring of liver function tests and blood glucose should be performed to ascertain that the drug is producing no adverse effects on these organ systems. Diabetic patients may experience a dose-related rise in glucose tolerance, the clinical significance of which is unclear. Diabetic or potentially diabetic patients should be observed closely. Adjustment of diet and/or hypoglycemic therapy may be necessary.

Caution should also be used when NIASPAN is used in patients with unstable angina or in the acute phase of MI, particularly when such patients are also receiving vasoactive drugs such as nitrates, calcium channel blockers, or adrenergic blocking agents.

Elevated uric acid levels have occurred with niacin therapy, therefore use with caution in patients predisposed to gout.

NIASPAN has been associated with small but statistically significant dose-related reductions in platelet count (mean of -11% with 2000mg). In addition, NIASPAN has been associated with small but statistically significant increases in prothrombin time (mean of approximately +4%); accordingly, patients undergoing surgery should be carefully evaluated. Caution should be observed when NIASPAN is administered concomitantly with anticoagulants; prothrombin time and platelet counts should be monitored closely in such patients.

In placebo-controlled trials, NIASPAN has been associated with small but statistically significant, dose-related reductions in phosphorus levels (mean of -13% with 2000mg). Although these reductions were transient, phosphorus levels should be monitored periodically in patients at risk for hypophosphatemia.

Niacin is rapidly metabolized by the liver, and excreted through the kidneys. NIASPAN is contraindicated in patients with significant or unexplained hepatic dysfunction (see CONTRAINDICATIONS and ) and should be used with caution in patients with renal dysfunction.

Information for Patients

Patients should be advised:

Drug Interactions

HMG-CoA Reductase Inhibitors:    See , Skeletal Muscle .

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

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

Bile Acid Sequestrants:    An in vitro study was carried out investigating the niacin-binding capacity of colestipol and cholestyramine. About 98% of available niacin was bound to colestipol, with 10 to 30% binding to cholestyramine. These results suggest that 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 NIASPAN.

Other:    Concomitant alcohol or hot drinks may increase the side effects of flushing and pruritus and should be avoided around the time of NIASPAN ingestion. Vitamins or other nutritional supplements containing large doses of niacin or related compounds such as nicotinamide may potentiate the adverse effects of NIASPAN.

Drug/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.

Carcinogenesis, Mutagenesis, Impairment of Fertility

Niacin administered to mice for a lifetime as a 1% solution in drinking water was not carcinogenic. The mice in this study received approximately 6 to 8 times a human dose of 3000 mg/day as determined on a mg/m 2 basis. Niacin was negative for mutagenicity in the Ames test. No studies on impairment of fertility have been performed. No studies have been conducted with NIASPAN regarding carcinogenesis, mutagenesis, or impairment of fertility.

Pregnancy

Pregnancy Category C.

Animal reproduction studies have not been conducted with niacin or with NIASPAN. It is also not known whether niacin at doses typically used for lipid disorders can cause fetal harm when administered to pregnant women or whether it can affect reproductive capacity. If a woman receiving niacin for primary hypercholesterolemia (Types IIa or IIb) becomes pregnant, the drug should be discontinued. If a woman being treated with niacin for hypertriglyceridemia (Types IV or V) conceives, the benefits and risks of continued therapy should be assessed on an individual basis.

Nursing Mothers

Niacin has been reported to be excreted in human milk. Because of the potential for serious adverse reactions in nursing infants from lipid-altering doses of nicotinic acid, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother. No studies have been conducted with NIASPAN in nursing mothers.

Pediatric Use

Safety and effectiveness of niacin therapy in pediatric patients (</=16 years) have not been established. No studies in patients under 21 years of age have been conducted with NIASPAN.

ADVERSE REACTIONS

NIASPAN is generally well tolerated; adverse reactions have been mild and transient. In the placebo-controlled clinical trials, flushing episodes (i.e., warmth, redness, itching and/or tingling) were the most common treatment-emergent adverse events (reported by as many as 88% of patients) for NIASPAN. Spontaneous reports suggest that flushing may also be accompanied by symptoms of dizziness, tachycardia, palpitations, shortness of breath, sweating, chills, and/or edema, which in rare cases may lead to syncope. In pivotal studies, fewer that 6% (14/245) of NIASPAN patients discontinued due to flushing. In comparisons of immediate-release (IR) niacin and NIASPAN, although the proportion of patients who flushed was similar, fewer flushing episodes were reported by patients who received NIASPAN. Following 4 weeks of maintenance therapy at daily doses of 1500mg, the incidence of flushing over the 4-week period averaged 8.56 events per patient for IR niacin versus 1.88 following NIASPAN.

Other adverse events occurring in 5% or greater of patients treated with NIASPAN, at least remotely related to NIASPAN, are shown in Table 9 below.

Table 9  Treatment-Emergent Adverse Events by Dose Level in >/=5% of Patients;
Events Considered At Least Remotely Related to Study Medication
 
Placebo-Controlled Studies
NIASPAN Treatment #
  Recommended Daily
Maintenance Doses
Greater Than Recommended
Daily Doses
Placebo
(n=157)
%
500mg &
(n=87)
%
1000mg
(n=110)
%
1500mg
(n=136)
%
2000mg
(n=95)
%
2500mg &
(n=49)
%
3000mg &
(n=46)
%
15 5 * 9 11 8 4 * 4
3 1 2 5 3 0 2
3 3 2 3 5 0 0
8 6 7 6 8 10 11
8 2 4 5 5 6 0
4 2 5 3 8 10 4
2 0 2 3 8 * 8 2
7 2 5 4 3 0 0
1 6 <1  3 1 0 0
<1  5 5 4 0 0 0
Note: Percentages are calculated from the total number of patients in each column. AEs are reported at the lowest dose where they occurred.
# Pooled results from placebo-controlled studies; for NIASPAN, n=245 and mean treatment duration = 17 weeks. Number of NIASPAN patients (n) are not additive across doses.
& The 500mg, 2500mg and 3000mg/day doses are outside the recommended daily maintenance dosing range; see DOSAGE AND ADMINISTRATION .
* Significantly different from placebo at p </=0.05; Chi-square test (cell size>5), Fisher' Exact test (cell sizes</=5).
In general, the incidence of adverse events was higher in women compared to men.

The following adverse events have also been reported with niacin products, either during clinical trials or in routine patient management.

Body as a Whole:   edema, asthenia, chills

Cardiovascular   atrial fibrillation, and other cardiac arrhythmias; tachycardia, palpitations; orthostasis; syncope; hypotension

Eye:   toxic amblyopia, crystoid macular edema

Gastrointestinal:   activation of peptic ulcers and peptic ulceration; jaundice

Metabolic:   decreased glucose tolerance; gout

Musculoskeletal:   myalgia

Nervous:   dizziness, insomnia

Skin:   hyper-pigmentation; maculopapular rash; acanthosis nigricans; urticaria; dry skin; sweating

Other:   migraine

Clinical Laboratory Abnormalities

Chemistry   Elevations in serum transaminases (see - Liver Dysfunction ), LDH, fasting glucose, uric acid, total bilirubin, and amylase; reductions in phosphorus

Hematology:   Slight reductions in platelet counts and prolongation in prothrombin time (see )

DRUG ABUSE AND DEPENDENCE

Niacin is a non-narcotic drug. It has no known addiction potential in humans.

OVERDOSE

Supportive measures should be undertaken in the event of an overdosage.

DOSAGE AND ADMINISTRATION

NIASPAN should be taken at bedtime, after a low-fat snack, and doses should be individualized according to patient response. Therapy with NIASPAN must be initiated at 500 mg qhs in order to reduce the incidence and severity of side effects which may occur during early therapy. The recommended dose escalation is shown in Table 10 below.

Table 10. Recommended Dosing
      Weeks Daily dose NIASPAN Dosage
I
N
I
T
I
A
L
T
I
T
R
A
T
I
O
N
S
C
H
E
D
U
L
E
1 to 4 500mg 1 NIASPAN 500mg tablet
at bedtime
5 to 8 1000mg 2 NIASPAN 500mg tablets
at bedtime
      * 1500mg 2 NIASPAN 750mg tablets or
3 NIASPAN 500mg tablets
at bedtime
      * 2000mg 2 NIASPAN 1000mg tablets or
4 NIASPAN 500mg tablets
at bedtime
* After Week 8, titrate to patient response and tolerance. If response to 1000mg daily is inadequate, increase dose to 1500mg daily; may subsequently increase dose to 2000mg daily. Daily dose should not be increased more than 500mg in a 4-week period, and doses above 2000mg daily are not recommended. Women may respond at lower doses than men.

Maintenance Dose:

The daily dosage of NIASPAN should not be increased by more than 500mg in any 4-week period. The recommended maintenance dose is 1000mg (two 500mg tablets) to 2000mg (two 1000mg tablets or four 500mg tablets) once daily at bedtime. Doses greater than 2000mg daily are not recommended. Women may respond at lower NIASPAN doses than men (see , Gender Effect ).

If lipid response to NIASPAN alone is insufficient, or if higher doses of NIASPAN are not well tolerated, some patients may benefit from combination therapy with a bile-acid binding resin or an HMG-CoA reductase inhibitor. (see , PRECAUTIONS , Drug Interactions , Concomitant Therapy below, and , NIASPAN Clinical Studies )

Flushing of the skin (see ADVERSE REACTIONS ) may be reduced in frequency or severity by pretreatment with aspirin (taken 30 minutes prior to NIASPAN dose) or non-steroidal anti-inflammatory drugs. Tolerance to this flushing develops rapidly over the course of several weeks. Flushing, pruritus, and gastrointestinal distress are also greatly reduced by slowly increasing the dose of niacin and avoiding administration on an empty stomach.

Equivalent doses of NIASPAN should not be substituted for sustained-release (modified-release, timed-release) niacin preparations or immediate-release (crystalline) niacin (see ). Patients previously receiving other niacin products should be started with the recommended NIASPAN titration schedule (see Table 10), and the dose should subsequently be individualized based on patient response. Single-dose bioavailability studies have demonstrated that NIASPAN tablet strengths are not interchangeable.

If NIASPAN therapy is discontinued for an extended period, reinstitution of therapy should include a titration phase (see Table 10).

NIASPAN tablets should be taken whole and should not be broken, crushed or chewed before swallowing.

Concomitant Therapy

Preliminary evidence suggests that the lipid-lowering effects of NIASPAN on TC and LDL-C are enhanced with an HMG-CoA reductase inhibitor, e.g., lovastatin, pravastatin, simvastatin, and fluvastatin. Additive effects on LDL-C are also seen when niacin is combined with bile acid binding resins. (see and PRECAUTIONS , Drug Interactions )

Dosage in Patients with Renal or Hepatic Insufficiency

Use of NIASPAN in patients with renal or hepatic insufficiency has not be studied. NIASPAN is contraindicated in patients with significant or unexplained hepatic dysfunction. NIASPAN should be used with caution in patients with renal insufficiency (see , PRECAUTIONS ).

HOW SUPPLIED

NIASPAN is supplied as unscored, off-white capsule-shaped tablets containing 500, 750 or 1000mg of niacin in an extended-release formulation. Tablets are debossed KOS on one side and the tablet strength (500, 750 or 1000) on the other side. Tablets are supplied in bottles of 100 as shown below.

500mg tablets:     bottles of 100 - NDC# 60598-001-01

750mg tablets:     bottles of 100 - NDC# 60598-002-01

1000mg tablets:   bottles of 100 - NDC# 60598-003-01

Store at room temperature, (20 to 25°C or 68 to 77°F).

PRODUCT PHOTO(S):

NOTE: These photos can be used only for identification by shape, color, and imprint. They do not depict actual or relative size.

The product samples shown here have been supplied by the manufacturer and reproduced in full color by PDR as a quick-reference identification aid. While every effort has been made to assure accurate reproduction, please remember that any visual identification should be considered preliminary. In cases of poisoning or suspected overdosage, the drug' identity should be verified by chemical analysis.

images/pills/p01320a3.jpg

REFERENCES

  1. Bostom AG et al. JAMA . 1996; 276:544-548.
  2. The Coronary Drug Project Research Group. JAMA . 1975; 231:360-381.
  3. Canner PL et al. J Am Coll Cardiol . 1986; 8(6):1245-1255.
  4. Blankenhorn DH et al. JAMA . 1987; 257(23):3233-3240.
  5. Cashin-Hemphill L et al. JAMA . 1990; 264(23):3013-3017.
  6. Brown G et al. NEJM . 1990; 323:1289-1298.
  7. Pasternak RC et al. Annals Int Med . 1996; 125:529-540.
  8. Summary of the Second Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel II), JAMA . 1993;269:3015-3023.
  9. Nikkila EA, In: The Metabolic Basis of Inherited Disease . 5th ed. 1983. Chap. 30: 622-642.

Manufactured by:
Kos Pharmaceuticals, Inc.
Miami, FL 33131

400025/1199 ©1999 Kos Pharmaceuticals, Inc., Miami, FL 33131, USA