Effectiveness and Tolerability of Adding Ezetimibe to Niacin-Based Regimens for Treatment of Primary Hyperlipidemia

An International Atherosclerosis Society Position Paper: global recommendations for the management of dyslipidemia--full report

An international panel of the International Atherosclerosis Society has developed a new set of recommendations for the management of dyslipidemia. The panel identifies non--high-density lipoprotein cholesterol as the major atherogenic lipoprotein. Primary and secondary prevention are considered separately. Optimal levels for atherogenic lipoproteins are derived for the two forms of prevention. For primary prevention, the recommendations emphasize lifestyle therapies to reduce atherogenic lipoproteins; drug therapy is reserved for subjects at greater risk. Risk assessment is based on estimation of lifetime risk according to differences in baseline population risk in different nations or regions. Secondary prevention emphasizes use of cholesterol-lowering drugs to attain optimal levels of atherogenic lipoproteins.

Combinations of ezetimibe with nonstatin drug regimens affecting lipid metabolism

In this article we discuss the available data on the effects of combined therapy of ezetimibe with agents affecting lipid metabolism other than statins. We consider studies evaluating the effects of combined therapy of ezetimibe with bile acid sequestrants, fenofibrate, niacin, n-3 fatty acids, plant sterols, orlistat, metformin, acarbose and glitazones. Combination of ezetimibe with bile acid sequestrants (especially colesevelam) was shown to have additional effects on lipid parameters in patients with hyperlipidemia. Combination of ezetimibe with fenofibrate may be a good approach to improve the overall lipid profile of patients with mixed hyperlipidemia. The addition of ezetimibe to niacin-based therapy can be useful for high-risk patients with dyslipidemia who are not achieving their assigned treatment goals. For patients who cannot tolerate statins there are useful combinations of ezetimibe with other drugs affecting lipid metabolism. These combinations improve many metabolic parameters, but more trials should be carried out to reach more robust conclusions about their effects on cardiovascular disease prevention.

A "hot" topic in dyslipidemia management--"how to beat a flush": optimizing niacin tolerability to promote long-term treatment adherence and coronary disease prevention

Niacin is the most effective lipid-modifying agent for raising high-density lipoprotein cholesterol levels, but it also causes cutaneous vasodilation with flushing. To determine the frequency of flushing in clinical trials, as well as to delineate counseling and treatment approaches to prevent or manage flushing, a MEDLINE search was conducted of English-language literature from January 1, 1985, through April 7, 2009. This search used the title keywords niacin or nicotinic acid crossed with the Medical Subject Headings adverse effects and human. Niacin flushing is a receptor-mediated, mainly prostaglandin D(2)-driven phenomenon, the frequency, onset, and duration of which are largely determined by the distinct pharmacological and metabolic profiles of different niacin formulations. Subjective assessments include ratings of redness, warmth, itching, and tingling. In clinical trials, most (>60%) niacin users experienced mild or moderate flushing, which tended to decrease in frequency and severity with continued niacin treatment, even with advancing doses. Approximately 5% to 20% of patients discontinued treatment because of flushing. Flushing may be minimized by taking niacin with meals (or at bedtime with a low-fat snack), avoiding exacerbating factors (alcohol or hot beverages), and taking 325 mg of aspirin 30 minutes before niacin dosing. The current review advocates an initially slow niacin dose escalation from 0.5 to 1.0 g/d during 8 weeks and then from 1.0 to 2.0 g in a single titration step (if tolerated). Through effective counseling, treatment prophylaxis with aspirin, and careful dose escalation, adherence to niacin treatment can be improved significantly. Wider implementation of these measures should enable higher proportions of patients to reach sufficient niacin doses over time to prevent cardiovascular events.

LDL = 5: Virtues and dangers of multidrug therapy of low-density lipoprotein cholesterol

Multiple-drug therapy of dyslipidemia is frequently used to achieve treatment goals in high-risk patients with coronary artery disease. The authors report a case of a patient treated with a statin, fibrate, ezetimibe, and niacin in whom a calculated low-density lipoprotein cholesterol level of 5 mg/dL was achieved.

Tolerability and effects on lipids of ezetimibe coadministered with pravastatin or simvastatin for twelve months: results from two open-label extension studies in hypercholesterolemic patients

OBJECTIVE

The aim of these studies was to assess the long-term tolerability and effects on lipids of ezetimibe coadministered with pravastatin or simvastatin during treatment of hypercholesterolemic patients.

METHODS

Two separate 12-month, open-label extension studies enrolled patients who had successfully completed one of three 12-week, double-blind, placebo-controlled trials of ezetimibe coadministered with pravastatin, lovastatin, or simvastatin. In the extensions, the initial dose of each drug administered was 10 mg/d, with the option to up-titrate the statins if low-density lipoprotein cholesterol (LDL-C) goals were not met. Tolerability was assessed using monitoring of clinical and laboratory adverse events (AEs). Changes from baseline in LDL-C, total cholesterol, high-density lipoprotein cholesterol, and triglyceride levels were calculated.

RESULTS

Overall, 436 patients received ezetimibe + pravastatin 10 to 40 mg/d, including patients from the parent studies who received coadministration treatment but did not continue in the extension studies; 359 patients received ezetimibe + simvastatin 10 to 80 mg/d in the extension study. The majority of patients in both studies were white (ezetimibe + pravastatin, 374 [86%]; ezetimibe + simvastatin, 314 [87%]) and female (ezetimibe + pravastatin, 246 [56%]; ezetimibe + simvastatin, 210 [58%]). The mean ages were 55.7 and 57.7 years and the mean body mass indexes were 29.4 and 28.8 kg/m2 in the ezetimibe + pravastatin and ezetimibe + simvastatin studies, respectively. The most commonly reported AEs with ezetimibe + pravastatin were upper respiratory tract infection (78 [18%]), headache (47 [11%]), musculoskeletal pain (45 [10%]), arthralgia (43 [10%]), and sinusitis (42 [10%]); with ezetimibe + simvastatin, they were upper respiratory tract infection (67 [19%]), arthralgia (39 [11%]), and musculoskeletal pain (37 [10%]). AEs considered treatment related were reported in 98 (22%) and 80 (22%) patients in the ezetimibe + pravastatin and ezetimibe + simvastatin studies, respectively. Serious AEs were reported in 29 patients (7%) who received ezetimibe + pravastatin and 36 patients (10%) who received ezetimibe + simvastatin; <1% were considered treatment related in either study. Forty-one (9%) and 29 patients (8%), respectively, were withdrawn due to AEs. One death occurred due to cardiopulmonary arrest in the ezetimibe + simvastatin study and was not considered treatment related. Percentage changes from baseline in LDL-C were -36.5% and -40.4% in patients who received ezetimibe + pravastatin and ezetimibe + simvastatin.

CONCLUSION

In these 12-month, open-label extension studies in these patients with hypercholesterolemia, ezetimibe + pravastatin or simvastatin was generally well tolerated. Both treatments were associated with maintaining improvements in lipid parameters throughout the studies in these patients.

Long-term safety and tolerability of ezetimibe coadministered with simvastatin in hypercholesterolemic patients: a randomized, 12-month double-blind extension study

OBJECTIVES

To assess the long-term safety and tolerability and to further evaluate the effect of ezetimibe plus simvastatin on LDL-C, HDL-C, and triglyceride levels in subjects with primary hypercholesterolemia.

METHODS

This was a 12-month, double-blind, placebo-controlled extension study that enrolled patients with primary hypercholesterolemia who had successfully completed the 12-week, double-blind, placebo-controlled trial of ezetimibe coadministered with simvastatin. The initial dose administered to patients in the extension was ezetimibe 10 mg coadministered with simvastatin 10 mg with the option to up-titrate statin dosage if LDL-C goals were not met. Safety and tolerability were assessed through clinical and laboratory adverse experiences (AEs). Changes from baseline in low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and triglyceride levels were measured.

RESULTS

Overall, 87 patients were randomized to receive ezetimibe + simvastatin and 22 were randomized to receive simvastatin and placebo. Treatment-emergent AEs were reported for 72/87 (83%) ezetimibe + simvastatin-treated patients and for 17/22 (77%) simvastatin-treated patients. The most commonly reported AEs in the simvastatin treatment group were hypertension, gastro-esophageal reflux, and musculoskeletal pain (each reported by 3/22 [14%] patients); and in the ezetimibe + simvastatin group were upper respiratory tract infection (16/87 [18%]), arthralgia and musculoskeletal pain (both reported by 10/87 [11%] patients). Drug-related AEs were reported for 3/22 (14%) simvastatin-treated patients and 21/87 (24%) patients in the coadministration group. AEs considered serious by the investigator were reported by 2/22 (9%) patients taking simvastatin monotherapy and by 20/87 (23%) patients taking ezetimibe + simvastatin. Discontinuations due to AEs occurred in no patients taking simvastatin monotherapy and in 7/87 (8%) patients taking ezetimibe + simvastatin. Percent change ± standard deviation from baseline in LDL-C was -29% ± 15.4 and -44% ± 14.2 in subjects taking simvastatin monotherapy and ezetimibe + simvastatin, respectively.

CONCLUSIONS

Ezetimibe coadministered with simvastatin was generally well-tolerated and no new safety concerns were raised. Both treatments effectively maintained improvements in lipid parameters throughout the course of the studies. Interpretation of these results was limited by the small convenience sample included in the trial.

The effects of ezetimibe on LDL-cholesterol: quantitative or qualitative changes?

Ezetimibe represents the first of a new class of agents, the cholesterol absorption inhibitors, able to reduce low-density lipoproteins (LDL)-cholesterol by 15-25% from baseline in monotherapy and on top of statins and fibrates. To-date all the data regarding the efficacy of ezetimibe comes from the studies of its lipid-lowering power. Yet, recent findings from the ENHANCE study on atherosclerosis progression showed that the addition of ezetimibe to simvastatin in patients with heterozygous familial hypercholesterolemia did not affect the mean change in carotid intima-media thickness, although a significant reduction in LDL-cholesterol levels was present. Therefore, we cannot exclude that ezetimibe is treating mainly LDL-cholesterol and not the underlying dyslipidemia. Reviewing all available evidences on the effects on atherogenic small, dense LDL, it seems that ezetimibe produce quantitative rather than qualitative changes in LDL, with small net effects on LDL subclass distribution. Yet, we cannot exclude that clinical and laboratory factors influenced this result. We found important differences in the methodology used to measure LDL size and subfractions and this represents a crucial point, since these methods cannot be fully used interchangeably. In addition, it is reasonable to imagine that ezetimibe may be more effective on small, dense LDL in subjects with hypertriglyceridemia. Further formal cardiovascular event outcome trials are underway and this will provide additional insights into the long-term effects of ezetimibe. Future prospective studies are also needed to clarify to which extent ezetimibe is able to reduce atherogenic dyslipidemia, beyond LDL-cholesterol levels.

Ezetimibe-associated adverse effects: what the clinician needs to know

OBJECTIVE

Ezetimibe is a relatively new lipid lowering agent, which is indicated for the treatment of primary hypercholesterolaemia, either as monotherapy or in combination with other hypolipidaemic drugs. The objective of the present article was to review the side effects attributed to ezetimibe administration and discuss their possible underlying mechanisms. Moreover, we aimed to comment on the possible drug interactions of ezetimibe and present current guidelines regarding its safe use.

METHODS

Relevant articles were identified through a PubMed search (up to June 2007).

RESULTS

Compelling evidence from the majority of the data reviewed here showed that adverse effects associated with ezetimibe use are few and mild without having been associated with serious clinical outcomes. In most studies ezetimibe has not been associated with increased rates of myopathy or rhabdomyolysis, whether used alone or in combination with statins, although there have been some case reports of myopathy attributed to this agent. Moreover, ezetimibe has been associated with mild elevations of liver transaminases, mainly in combination with a statin. Other side effects are extremely rare. It should be noted, however, there are no long-term safety data or outcome studies for ezetimibe yet.

CONCLUSIONS

Ezetimibe is a safe alternative option for hyperlipidaemic patients intolerant to other lipid lowering drugs as well as a beneficial supplementary agent for patients who do not reach the recommended serum cholesterol level with their current hypolipidaemic treatment. However, as is the case with all new medications, physicians should be alert to recognise adverse effects associated with ezetimibe and report them to regulatory authorities.

Ezetimibe: an update on the mechanism of action, pharmacokinetics and recent clinical trials

Elevated serum cholesterol is a known risk factor for the development of coronary artery disease. Circulating cholesterol is a product of both cholesterol absorption from the gut and cellular cholesterol production. Ezetimibe is a novel cholesterol-lowering drug that acts at the brush border of the small intestine. Recent studies have further identified the molecular target as the Niemann-Pick C1-like transporter. Ezetimibe blocks the absorption of dietary and biliary cholesterol and plant sterols resulting in intracellular cholesterol depletion. Clinical studies have demonstrated beneficial improvements in the lipid profile with ezetimibe as monotherapy, but dramatic effects are seen when ezetimibe is combined with other lipid-lowering drugs, particularly 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins). Combination studies of ezetimibe with statins, bile acid sequestrants, fenofibrate and niacin all demonstrate significant total and low density lipoprotein cholesterol lowering. An excellent safety and tolerability profile combined with once-daily dosing make this attractive adjunct therapy for the treatment of hypercholesterolemia.

Non-low-density lipoprotein cholesterol-associated actions of ezetimibe: an overview

Ezetimibe, an intestinal cholesterol absorption inhibitor, lowers circulating low-density lipoprotein cholesterol (LDL-C) levels both when administered as monotherapy and in combination with other hypolipidaemic drugs, mostly statins. This review focuses on the effects of ezetimibe on non-LDL-C-associated variables. In most studies, ezetimibe effectively reduced triglyceride and increased high density lipoprotein cholesterol levels. The authors also consider the effect of ezetimibe on other variables such as C-reactive protein levels, insulin sensitivity and endothelial function. Ezetimibe is useful in patients with sitosterolaemia (a rare inherited disorder) as it significantly reduces plasma phytosterol concentrations. Ezetimibe fulfils two of the three essential characteristics of any drug (efficacy and safety). However, clinical studies are required to provide evidence of its ability to reduce vascular events.