Am J Cardiol 1998 Dec 17;82(12A):74U-81U;
Efficacy and safety of an extended-release niacin (Niaspan): a long-term study.
Capuzzi DM, Guyton JR, Morgan JM, Goldberg AC, Kreisberg RA, Brusco OA, Brody J.
Department of Medicine, Cardiovascular Disease Prevention Center, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.
Crystalline nicotinic acid (immediate-release niacin) is effective therapy for lipoprotein regulation and cardiovascular risk reduction. However, inconvenient regimens and unpleasant side effects decrease compliance. Sustained-release formulations designed to circumvent these difficulties increase hepatotoxicity. Niaspan, a new US Food and Drug Administration (FDA)-approved, once-daily, extended-release form, has been found effective and safe in short-term trials. The long-term efficacy and safety of Niaspan lipid monotherapy was studied in 517 patients (aged 21-75 years) for < or =96 weeks in dosages < or =3,000 mg/day. Primary efficacy endpoints were low-density lipoprotein (LDL) cholesterol and apolipoprotein B (apo B) changes from baseline; secondary efficacy endpoints were changes in total cholesterol, triglycerides, high-density lipoprotein (HDL) cholesterol, lipoprotein(a), and total cholesterol/HDL-cholesterol ratio; safety data included adverse events and laboratory values over the 2-year study period. LDL-cholesterol levels decreased significantly: 18% at week 48 and 20% at week 96; apo B reduction was similar (16% decrease at week 48 and 19% at week 96). Large elevations in HDL cholesterol (26%, week 48; 28%, week 96) allowed only modest decreases in total cholesterol (12% and 13%, respectively), whereas total cholesterol/HDL-cholesterol ratio decreased by almost one third. Triglyceride and lipoprotein(a) levels were decreased by 27% and 30%, respectively (week 48), and by 28% and 40%, respectively (week 96). All changes from baseline were significant (p <0.001). Niaspan was generally well tolerated, although flushing was common (75%); however, there was a progressive decrease in flushing with time from 3.3 episodes in the first month to < or = 1 episode by week 48. Aspirin was used by one third of patients before Niaspan dosing to minimize flushing episodes. Although serious adverse events occurred in about 10% of patients, none were considered probably or definitely related to Niaspan. Adverse events in general varied widely, but their true relation to the study drug is difficult to ascertain without a placebo (control) group. No deaths occurred. There were statistically significant changes in hepatic transaminases, alkaline phosphatase, direct bilirubin, phosphorus, glucose, amylase, and uric acid. However, these changes were mostly small and are not likely to be biologically or clinically significant (the decrease in phosphorus is a new finding in niacin therapy). No myopathy was observed. Thus, this long-term study confirms the earlier short-term findings that Niaspan is safe and effective as monotherapy in plasma lipoprotein regulation.
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Am J Cardiol 1998 Dec 17;82(12A):29U-34U;
A new extended-release niacin (Niaspan): efficacy, tolerability, and safety in hypercholesterolemic patients.
Morgan JM, Capuzzi DM, Guyton JR.
Thomas Jefferson University Hospital, Philadelphia, Pennsylvania 19107, USA.
Immediate-release niacin manifests beneficial effects in cardiovascular disease with respect to dyslipidemic states. It lowers low-density lipoprotein (LDL) cholesterol, triglycerides, lipoprotein(a), and apoprotein B; at the same time, it increases high-density lipoprotein (HDL) cholesterol, HDL2, and apoprotein A-I. However, use of crystalline niacin has drawbacks: therapy requires multidose regimens, and side effects include flushing and pruritus. Slowing absorption with sustained-release formulations succeeds in decreasing flushing and increasing tolerance, but increases in hepatic enzyme levels have raised safety concerns. A new extended-release, once-daily formulation of niacin (Niaspan) shows promise in minimizing flushing while avoiding hepatotoxicity. A multicenter, randomized, double-blind clinical trial of Niaspan enrolled 122 patients with confirmed diagnosis of primary dyslipidemia (LDL cholesterol >4.14 mmol/L [160 mg/dL] and triglycerides <9 mmol/L [800 mg/dL]) into 3 treatment groups: (1) Niaspan 1,000 mg/day; (2) Niaspan 2,000 mg/day; and (3) placebo. The primary treatment endpoint was LDL-cholesterol level. This endpoint was not significantly affected by placebo (0.2% increase), but Niaspan decreased LDL cholesterol by 5.8% (1,000 mg/day) and 14.6% (2,000 mg/day) (p <0.001). Likewise, with placebo there were significant changes in total cholesterol, triglycerides, lipoprotein(a), and apoprotein B, whereas both Niaspan 1,000 and 2,000 mg/day significantly (p <0.001) decreased these parameters. In addition, both Niaspan groups showed significant (p <0.001) increases in HDL cholesterol (17% and 23%, respectively), including HDL subfractions. With respect to flushing, 20% of the placebo group reported at least 1 episode, whereas 88% and 83% of the Niaspon 1,000- and 2,000-mg/day groups, respectively, reported episodes. There was no hepatotoxicity as liver enzyme levels remained within clinically accepted limits in all treatment groups. However, Niaspan 2,000 mg/day showed a significant increase in aspartate aminotransferase compared with baseline and placebo. This trial demonstrated a cholesterol-modifying effect of Niaspan consistent with those reported for niacin, but demonstrated a better tolerance for flushing. Moreover, in contrast to sustained-release formulations, Niaspan showed relatively mild hepatic effects.
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Before 1995, sustained release Niacin bought over-the-counter damaged liver more than regular Niacin. However, as the above studies show the prescription form of Niacin called Niaspan which is time-released has been shown to cause less liver damage.
JAMA 1994 Mar 2;271(9):672-7
A comparison of the efficacy and toxic effects of sustained- vs immediate-release niacin in hypercholesterolemic patients.
McKenney JM, Proctor JD, Harris S, Chinchili VM.
School of Pharmacy, Medical College of Virginia, Virginia Commonwealth University, Richmond 23298.
OBJECTIVE--To compare escalating doses of immediate-release (IR) and sustained-release (SR) niacin for effectiveness in reducing levels of low-density lipoprotein cholesterol and triglycerides and increasing levels of high-density lipoprotein cholesterol, and for the occurrence of adverse reactions, especially hepatotoxicity. DESIGN--Randomized, double-blind, parallel comparison of IR and SR niacin administered sequentially at 500, 1000, 1500, 2000, and 3000 mg/d, each for 6 weeks. SETTING--Cholesterol research center. PATIENTS--Forty-six adults, 23 in each group, with low-density lipoprotein cholesterol levels greater than 4.14 mmol/L (160 mg/dL) after 1 month of a step 1 National Cholesterol Education Program diet. OUTCOME MEASURES--Fourteen-hour fasting lipid and lipoprotein cholesterol levels, results of clinical laboratory tests, a symptom questionnaire, and withdrawal rates. RESULTS--The SR niacin lowered low-density lipoprotein cholesterol levels significantly more than IR niacin did at the dosage of 1500 mg/d and above, while IR niacin increased high-density lipoprotein cholesterol levels significantly more than SR niacin did at all dosage levels. The reduction in triglyceride levels was similar with IR and SR niacin. Nine (39%) of the 23 patients assigned to the IR dosage form withdrew before completing the 3000-mg daily dose; the most common reasons for withdrawal were vasodilatory symptoms, fatigue, and acanthosis nigricans. Eighteen (78%) of the 23 patients assigned to the SR dosage form withdrew before completing the 3000-mg daily dose; the most common reasons for withdrawal were gastrointestinal tract symptoms, fatigue, and increases in levels of liver aminotransferases, often with symptoms of hepatic dysfunction. None of the patients taking IR niacin developed hepatotoxic effects, while 12 (52%) of the 23 patients taking SR niacin did. CONCLUSION--The SR form of niacin is hepatotoxic and should be restricted from use. The IR niacin is preferred for the management of hypercholesterolemia but can also cause significant adverse effects and should be given only to patients who can be carefully monitored by experienced health professionals.
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Heart Dis 2002 Mar-Apr;4(2):124-37
Lovastatin and extended-release niacin combination product: the first drug combination for the management of hyperlipidemia.
Gupta EK, Ito MK.
University of the Pacific Thomas J. Long School of Pharmacy and Health Sciences, Stockton, California, USA.
Advicor (lovastatin and extended-release niacin) is the first cholesterol-lowering combination product to become available for the management of hyperlipidemia. Lovastatin significantly lowers low-density lipoprotein cholesterol, whereas niacin significantly lowers triglycerides and lipoprotein (a) and markedly increases high-density lipoprotein cholesterol. These effects are ideal for managing a variety of lipid disorders, including metabolic syndrome. Lovastatin and niacin reduce coronary heart disease mortality in primary and secondary prevention patients, respectively. The extended-release niacin component uses a unique technology to minimize adverse effects (e.g., flushing and hepatotoxicity) while retaining the same lipid-altering effects as immediate-release niacin. The combination product appears to be well tolerated, with discontinuation due to adverse effects other than flushing occurring in a similar percent of patients as for lovastatin in clinical trials. Approximately 9% of patients discontinued the combination product due to flush. No confined cases of myopathy or hepatotoxicity have been reported with this product. Once-daily dosing provides ease of administration that should improve compliance and result in a greater proportion of patients meeting their low-density lipoprotein cholesterol goals. The nomenclature surrounding niacin products used to treat dyslipidemias is confusing. While only two types of niacin formulations exist (immediate-release formulations and formulations which dissolve more slowly than immediate-release formulations), government regulations allow for slowly dissolved niacin formulations to be divided into two types of niacin products; those that are available over-the-counter (OTC) and those that are available by prescription only. Over-the-counter slowly dissolved niacin preparations are not classified as OTC per se, but are considered "nutritional supplements". For this reason, they fall under the jurisdiction of the Federal Trade Commission and do not fall under the umbrella of the FDA branch that controls dyslipidemic products (Endocrine and Metabolic Division of the Center for Drug Evaluation and Research). The slowly dissolved niacin nutritional supplements have not been reviewed by the FDA for safety nor efficacy in the treatment of dyslipidemia nor are they required to meet generic drug rules (even though various brands are available). These brands are described on their labels as "sustained-release", "timed-release", and "slow-release" for example. Only two slowly absorbed niacin products have been approved by the FDA for the treatment of dyslipidemia; they are Niaspan (Kos Pharmaceuticals, Inc., Miami, FL) and Advicor (Kos Pharmaceuticals, Inc., Miami, FL) . The term "extended-release" has been given to these two products to simplify the terminology and differentiate the products from immediate-release niacin. In this review, we will use "extended-release" to refer to the FDA approved slowly dissolving niacin preparation and "sustained-release" to refer to the nutritional supplements (not FDA approved).
Last edited by Voyajer : Sun, Aug-18-02 at 15:25.
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