What's the deal with niacin development: is laropiprant add-on therapy a winning strategy to beat a straight flush?

Anti-Obesity Medications and Investigational Agents: An Obesity Medicine Association (OMA) Clinical Practice Statement (CPS) 2022

Background

This "Anti-Obesity Medications and Investigational Agents: An Obesity Medicine Association Clinical Practice Statement 2022" is intended to provide clinicians an overview of Food and Drug Administration (FDA) approved anti-obesity medications and investigational anti-obesity agents in development.

Methods

The scientific information for this Clinical Practice Statement (CPS) is based upon published scientific citations, clinical perspectives of OMA authors, and peer review by the Obesity Medicine Association leadership.

Results

This CPS describes pharmacokinetic principles applicable to those with obesity, and discusses the efficacy and safety of anti-obesity medications [e.g., phentermine, semaglutide, liraglutide, phentermine/topiramate, naltrexone/bupropion, and orlistat, as well as non-systemic superabsorbent oral hydrogel particles (which is technically classified as a medical device)]. Other medications discussed include setmelanotide, metreleptin, and lisdexamfetamine dimesylate. Data regarding the use of combination anti-obesity pharmacotherapy, as well as use of anti-obesity pharmacotherapy after bariatric surgery are limited; however, published data support such approaches. Finally, this CPS discusses investigational anti-obesity medications, with an emphasis on the mechanisms of action and summary of available clinical trial data regarding tirzepatide.

Conclusion

This "Anti-Obesity Medications and Investigational Agents: An Obesity Medicine Association Clinical Practice Statement 2022" is one of a series of OMA CPSs designed to assist clinicians in the care of patients with pre-obesity/obesity.

Extended-release niacin/laropiprant significantly improves lipid levels in type 2 diabetes mellitus irrespective of baseline glycemic control

Background

The degree of glycemic control in patients with type 2 diabetes mellitus (T2DM) may alter lipid levels and may alter the efficacy of lipid-modifying agents.

Objective

Evaluate the lipid-modifying efficacy of extended-release niacin/laropiprant (ERN/LRPT) in subgroups of patients with T2DM with better or poorer glycemic control.

Methods

Post hoc analysis of clinical trial data from patients with T2DM who were randomized 4:3 to double-blind ERN/LRPT or placebo (n=796), examining the lipid-modifying effects of ERN/LRPT in patients with glycosylated hemoglobin or fasting plasma glucose levels above and below median baseline levels.

Results

At Week 12 of treatment, ERN/LRPT significantly improved low-density lipoprotein cholesterol, high-density lipoprotein cholesterol (HDL-C), non-high-density lipoprotein cholesterol, triglycerides, and lipoprotein (a), compared with placebo, with equal efficacy in patients above or below median baseline glycemic control. Compared with placebo, over 36 weeks of treatment more patients treated with ERN/LRPT had worsening of their diabetes and required intensification of antihyperglycemic medication, irrespective of baseline glycemic control. Incidences of other adverse experiences were generally low in all treatment groups.

Conclusion

The lipid-modifying effects of ERN/LRPT are independent of the degree of baseline glycemic control in patients with T2DM (NCT00485758).

The role of extended-release niacin on immune activation and neurocognition in HIV-infected patients treated with antiretroviral therapy - CTN PT006: study protocol for a randomized controlled trial

BACKGROUND

Approximately 30% of HIV-1-infected patients receiving antiretroviral therapy who achieve virologic control have unsatisfactory immune reconstitution, with CD4+ T-cell counts persistently below 350 cells/μL. These patients are at elevated risk for clinical progression to AIDS and non-AIDS events. CD4+ T-cell depletion following infection and persistent immune activation can partially explain this low CD4+ T-cell recovery. Recent data suggest a link between the tryptophan oxidation pathway, immune activation and HIV disease progression based on overstimulation of the tryptophan oxidation pathway by HIV antigens and by interferon-gamma. This overstimulation reduces levels of circulating tryptophan, resulting in inflammation which has been implicated in the development of neurocognitive dysfunction. Niacin (vitamin B3) is able to control the excess tryptophan oxidation, correcting tryptophan depletion, and therefore represents an interesting strategy to improve CD4 recovery.We aim to design a crossover proof-of-concept study to assess supplementation with an extended-release form of niacin (Niaspan FCT™) in combination with antiretroviral therapy, compared to antiretroviral therapy alone, on T-cell immune activation as defined by changes in the percentage of CD8+ CD38+ HLA-DR+ T-cells.

METHODS/DESIGN

This randomized, open-label, interventional crossover study with an immediate versus deferred use of Niaspan FCT for 24 weeks will assess its ability to reduce immune activation and thus increase CD4 recovery in 20 HIV-infected individuals with suboptimal immune responses despite sustained virologic suppression. A substudy evaluating neurocognitive function will also be conducted.

DISCUSSION

This randomized trial will provide an opportunity to evaluate the potential benefit of oral extended-release niacin, a drug that can indirectly increase tryptophan, to reduce immune activation and in turn increase CD4+ T-cell recovery. The study will also allow for the evaluation of the impact of Niaspan FCT on neurocognitive function in HIV-infected individuals with suboptimal immune responses despite sustained virologic suppression.

TRIAL REGISTRATION

This study was registered with ClinicalTrials.gov on 17 December 2013 (registration number: NCT02018965).

Lowering low-density lipoprotein cholesterol levels in patients with type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) is characterized by hyperglycemia, insulin resistance, and/or progressive loss of β-cell function. T2DM patients are at increased risk of micro- and macrovascular disease, and are often considered as representing an atherosclerotic coronary heart disease (CHD) risk equivalent. Interventions directed at glucose and lipid level control in T2DM patients may reduce micro- and macrovascular disease. The optimal T2DM agent is one that lowers glucose levels with limited risk for hypoglycemia, and with no clinical trial evidence of worsening CHD risk. Lipid-altering drugs should preferably reduce low-density lipoprotein cholesterol and apolipoprotein B (apo B) and have evidence that the mechanism of action reduces CHD risk. Statins reduce low-density lipoprotein cholesterol and apo B and have evidence of improving CHD outcomes, and are thus first-line therapy for the treatment of hypercholesterolemia. In patients who do not achieve optimal lipid levels with statin therapy, or who are intolerant to statin therapy, add-on therapy or alternative therapies may be indicated. Additional available agents to treat hypercholesterolemic patients with T2DM include bile acid sequestrants, fibrates, niacin, and ezetimibe. This review discusses the use of these alternative agents to treat hypercholesterolemia in patients with T2DM, either as monotherapy or in combination with statin therapy.

Consistency of extended-release niacin/laropiprant effects on Lp(a), ApoB, non-HDL-C, Apo A1, and ApoB/ApoA1 ratio across patient subgroups

BACKGROUND

According to prior analyses, extended-release niacin/laropiprant (ERN/LRPT) consistently reduces low-density lipoprotein cholesterol (LDL-C) and triglycerides (TG) and increases high-density lipoprotein cholesterol (HDL-C) levels across a wide range of dyslipidemic patient subgroups.

OBJECTIVES

This analysis examined ERN/LRPT's consistency across four phase III, randomized, double-blind trials in improving other lipid/lipoprotein parameters associated with cardiovascular risk, across several key dyslipidemic patient subgroups.

METHODS

In three of the studies, the randomized population included patients with primary hypercholesterolemia or mixed hyperlipidemia; in the remaining study, the population included patients with type 2 diabetes mellitus. The lipid-altering consistency of ERN/LRPT's efficacy was evaluated versus the pre-defined comparator (placebo or active control) among key subgroups of sex, race (White, non-White), region (US, ex-US), baseline age (<65 years, ≥65 years), use of statin therapy (yes, no), coronary heart disease (yes, no), risk status (low, multiple, high), and type of hyperlipidemia (primary hypercholesterolemia, mixed dyslipidemia), as well as across baseline LDL-C, HDL-C, and TG levels. The consistency of the treatment effects on lipoprotein(a).[Lp(a)], apolipoprotein B (ApoB), non-HDL-C, ApoA1, and ApoB/ApoA1 ratio was evaluated by examining treatment difference estimates of the percentage change from baseline with 95% confidence intervals.

RESULTS

Treatment with ERN/LRPT produced significantly greater improvements in Lp(a), ApoB, non-HDL-C, ApoA1, and ApoB/ApoA1 ratio compared with placebo/active comparator in each study. These effects were generally consistent across key subgroups within each study.

CONCLUSION

ERN/LRPT produced lipid-altering efficacy on the parameters evaluated in four controlled studies; these effects were generally consistent across all examined subgroups. ERN/LRPT represents an effective and reliable therapeutic option for the treatment of dyslipidemia in a wide range of patient types.

CLINICAL TRIAL REGISTRATION

Registered as Clinicaltrials.gov NCT00269204, NCT00269217, NCT00479388, and NCT00485758.

Treatment options for the management of hypertriglyceridemia: strategies based on the best-available evidence

A severe elevation in triglycerides (TG; ≥500 mg/dL) increases the risk for pancreatitis. TG levels ≥200 mg/dL are associated with a greater risk of atherosclerotic coronary heart disease (CHD). However, no outcomes trials exist to assess the efficacy of TG lowering for preventing pancreatitis in patients with severe hypertriglyceridemia. Similarly, no completed prospective outcomes trial exists to support or refute a reduction in CHD risk resulting from lipid-altering therapy in patients specifically selected for the presence of hypertriglyceridemia. This review examines the available evidence for the use of statins, omega-3 fatty acids, fibrates, and niacin in the management of hypertriglyceridemic patients. Results from CHD outcomes trials support statins as the first-line lipid-altering drug therapy to reduce CHD in hypercholesterolemic patients, and subgroup analyses suggest statins are efficacious in hypertriglyceridemic patients with fasting TG levels <500 mg/dL. Omega-3 fatty acids and fibrates are reasonable first drug options for patients with TG ≥500 mg/dL and often are used to lower TG levels with the objective of reducing pancreatitis risk, although a statin or niacin may also be reasonable options. Combination lipid drug therapy may be needed to achieve both low-density lipoprotein cholesterol and non-high-density lipoprotein cholesterol treatment goals for CHD prevention in patients with elevated TG levels, particularly those with TG ≥500 mg/dL. Additional clinical outcomes data are needed to provide a more evidence-based rationale for clinical lipid management of hypertriglyceridemic patients.

Attenuation of niacin-induced prostaglandin D(2) generation by omega-3 fatty acids in THP-1 macrophages and Langerhans dendritic cells

Niacin, also known as nicotinic acid, is an organic compound that has several cardio-beneficial effects. However, its use is limited due to the induction of a variable flushing response in most individuals. Flushing occurs from a niacin receptor mediated generation of prostaglandins from arachidonic acid metabolism. This study examined the ability of docosahexaenoic acid, eicosapentaenoic acid, and omega-3 polyunsaturated fatty acids (PUFAs), to attenuate niacin-induced prostaglandins in THP-1 macrophages. Niacin induced both PGD₂ and PGE₂ generation in a dose-dependent manner. Niacin also caused an increase in cytosolic calcium and activation of cytosolic phospholipase A₂. The increase in PGD₂ and PGE₂ was reduced by both docosahexaenoic acid and eicosapentaenoic acid, but not by oleic acid. Omega-3 PUFAs efficiently incorporated into cellular phospholipids at the expense of arachidonic acid, whereas oleic acid incorporated to a higher extent but had no effect on arachidonic acid levels. Omega-3 PUFAs also reduced surface expression of GPR109A, a human niacin receptor. Furthermore, omega-3 PUFAs also inhibited the niacin-induced increase in cytosolic calcium. Niacin and/or omega-3 PUFAs minimally affected cyclooxygenase-1 activity and had no effect on cyclooxygenase -2 activity. The effects of niacin on PGD₂ generation were further confirmed using Langerhans dendritic cells. Results of the present study indicate that omega-3 PUFAs reduced niacin-induced prostaglandins formation by diminishing the availability of their substrate, as well as reducing the surface expression of niacin receptors. In conclusion, this study suggests that the regular use of omega-3 PUFAs along with niacin can potentially reduce the niacin-induced flushing response in sensitive patients.

Extended-release niacin/laropiprant effects on lipoprotein subfractions in patients with type 2 diabetes mellitus

BACKGROUND

A potentially atherogenic lipid profile often found in patients with type 2 diabetes mellitus (T2DM) includes increased concentrations of small, low-density lipoprotein (LDL) and intermediate-density lipoprotein (IDL) and decreased concentration of medium/large high-density lipoprotein (HDL) particles. Extended-release niacin/laropiprant (ERN/LRPT) lowers LDL-cholesterol (LDL-C) and triglycerides (TG), and raises HDL cholesterol (HDL-C) levels with attenuation of niacin-induced flushing.

METHODS

Plasma HDL, LDL, IDL, very-low-density lipoprotein (VLDL), and chylomicron particle concentration and size at were evaluated at baseline and week 12 using nuclear magnetic resonance (NMR). The data were acquired from a randomized, multicenter, double-blind, placebo-controlled study including 796 patients with T2DM treated with either 1 tablet of ERN 1 gram/LRPT 20 mg or matching placebo daily, increased after 4 weeks to 2 tablets daily.

RESULTS

ERN/LRPT significantly (P≤0.001 for all) reduced LDL-C 17.9% and TG 23.1%, and increased HDL-C levels 23.2%. Compared to placebo, ERN/LRPT decreased LDL, IDL, VLDL, and chylomicron particle concentrations [median concentration of smallest LDL particles decreased 16.6%, 95% confidence interval (CI) -22.3, -10.9, whereas the largest LDL particles decreased 11.0%, 95% CI -18.7, -3.2, and total VLDL/chylomicron mean plasma particle concentration decreased 34.7%, 95% CI -41.3, -28.1]. Compared to placebo, ERN/LRPT shifted the distribution of HDL particle diameter from smaller to larger (median concentration of the largest HDL particles increased 32.7% (95% CI 25.30, 40.58), whereas concentration of the smallest HDL particles decreased 8.2% (95% CI -11.29, -5.06).

CONCLUSIONS

Compared with placebo in patients with T2DM, ERN/LRPT shifted the lipoprotein profile toward a potentially less atherogenic pattern with reduced atherogenic LDL and IDL particle concentrations, and increased large HDL plasma particle concentrations. (ClinicalTrials.gov: NCT00485758).

Lipid lowering therapy in type 2 diabetes

The primary defect underlying abnormalities in lipoprotein transport in type 2 diabetes is insulin resistance, which leads to increased triglycerides in the fasting and postprandial states, preponderance of small, dense LDL and low concentrations of dysfunctional HDL. Concentrations of LDL-cholesterol (LDL-C) are most often not remarkably abnormal. Based on this lipoprotein profile, it seems somewhat counterintuitive to prioritize LDL-C lowering in type 2 diabetes. Nevertheless, ≈20 years of statins trials in >18,000 diabetic patients have unequivocally established this priority. Patients with type 2 diabetes without manifest atherosclerosis should reach an LDL-C goal <100 mg/dl or a Non-HDLcholesterol (NHDL-C) goal <130 mg/dl. If their baseline LDL-C is already between 70 and 100 mg/dl LDL-C should be lowered by 30 to 40%. Thus, the majority of these patients can be managed successfully with monotherapy using standard-intensity statins (e.g. simvastatin 40 mg/d). Patients with type 2 diabetes with manifest CHD should reach an LDL-C goal <70 mg/dl or an NHDL-C goal <100 mg/dl. A sizable fraction of these patients will require high-intensity statins (e.g. atorvastatin 80 mg/d or rosuvastatin 20-40 mg/d). If LDL-C goals are still not reached or high-intensity statins are not tolerated, combination of statins with ezetimibe is advisable. In patients with persistent pronounced dyslipidemic features, i.e. high TG/low HDL-C despite maximal lifestyle intervention and optimized statin dosage, pioglitazone should be incorporated in the antidiabetic management and combinations of statins with either niacin or fenofibrate should be considered. However, it has to be recognized that evidence supporting HDL-raising therapy is currently still much weaker than evidence supporting LDL lowering with statins.

Niacin extended-release therapy in phase III clinical trials is associated with relatively low rates of drug discontinuation due to flushing and treatment-related adverse events: a pooled analysis

BACKGROUND AND OBJECTIVE

Niacin is a highly effective agent for increasing low high-density lipoprotein cholesterol (HDL-C) levels. It also has beneficial effects on key pro-atherogenic lipoprotein parameters. However, the side effect of flushing can challenge patient adherence to treatment. In this study, we pooled safety data from available trials of at least 16 weeks' duration to evaluate the impact of flushing on patient adherence to niacin extended-release (NER) therapy.

METHODS

Data were pooled from eight NER studies (administered as NER with a maximum dosage of 1000, 1500, and 2000 mg/day, either as monotherapy or in combination with simvastatin 20 or 40 mg/day [NER/S], or lovastatin 20 or 40 mg/day [NER/L]) to evaluate rates of study discontinuation due to flushing or any treatment-related adverse events.

RESULTS

While 66.6% of patients experienced flushing, only 5.2% of patients discontinued treatment due to flushing. Of the total number of patients treated with NER (n = 307), NER/S (n = 912), or NER/L (n = 928), 34 (11%), 105 (11%), and 127 (14%) patients discontinued due to any treatment-related adverse event, respectively, while 14 (5%), 43 (5%), and 55 (6%) discontinued due to flushing. Discontinuation for flushing did not differ with regard to maximum dose, or to the presence or type of statin combined with NER.

CONCLUSION

Although flushing was common with NER treatment, discontinuation due to flushing occurred in only 5-6% of patients in this pooled analysis. This could be due to several factors, including the fact that all patients in the NER trials were educated about flushing and its management. Translation of methodology employed in these trials into clinical practice may improve long-term adherence to NER therapy, which would enhance the therapeutic benefit of NER for reducing cardiovascular risk.

Colesevelam hydrochloride powder for oral suspension versus cholestyramine powder for oral suspension: comparison of acceptability and tolerability

OBJECTIVE

To compare tolerability of colesevelam hydrochloride powder versus a cholesterol-lowering equivalent dose of generic cholestyramine powder, each mixed in water, by means of the validated Bile Acid Sequestrant Acceptability (BASA) Scale.

METHODS

We conducted a randomized, single-blind, single-visit, single-site study, comparing doses of 2 different bile acid sequestrant powders for oral suspension that produce similar cholesterol lowering: colesevelam hydrochloride (3.75 g) and generic cholestyramine (12 g), each mixed in a transparent cup with tap water.

RESULTS

The study sample consisted of 42 participants-12 men and 30 women. The study subjects were non-Hispanic white (64%) or black (36%), with a mean age of 50 years and a mean body mass index of 32.2 kg/m2. The components of the BASA Scale included taste, texture, appearance, and mixability. Colesevelam hydrochloride and cholestyramine did not differ significantly when assessed by both the unweighted and the weighted global BASA Scale. Although study participants indicated that the colorless or whitish colesevelam hydrochloride powder tasted better (P<.0001), they thought that the orange-colored cholestyramine had a more appealing appearance (P<.0001). Regarding the potential for taking the drug "for the rest of your life," 71.4% of study participants rated taste as "very important," and 11.9% rated appearance as "very important."

CONCLUSION

Although study participants thought that the orange-colored generic cholestyramine powder had a better appearance, they also reported that colesevelam hydrochloride for oral suspension tasted better. A minority of study participants thought appearance was "very important"; a substantial majority thought taste was "very important" for potential long-term compliance.

Extended-release niacin/laropiprant lipid-altering consistency across patient subgroups

BACKGROUND

In patients with primary hypercholesterolemia or mixed dyslipidemia, extended-release niacin/laropiprant (ERN/LRPT) improves key lipid parameters associated with increased atherosclerotic coronary heart disease (CHD) risk.

AIM

This analysis examined data from four Phase III, randomised, double-blind trials to determine the consistency of ERN/LRPT's lipid-altering efficacy among subgroups of patients.

METHODS

Data from four Phase III, randomised, double-blind trials of ERN/LRPT were analysed to determine the consistency of ERN/LRPT's lipid-altering efficacy among subgroups of gender, race (white, non-white), region (US, ex-US), baseline age (<65, ≥65 years), use of statin therapy, CHD risk status (low, multiple, high) and type of hyperlipidemia (primary hypercholesterolemia, mixed dyslipidemia), as well as across baseline low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglyceride (TG) levels. End-points included the per cent change from baseline in LDL-C, HDL-C and TG levels. Consistency of the treatment effects on LDL-C, HDL-C and TG across subgroups was evaluated by examining treatment difference estimates with 95% confidence intervals.

RESULTS

  Treatment with ERN/LRPT significantly improved LDL-C, HDL-C and TG levels compared with placebo/active comparator in each study cohort. These effects were generally consistent across all examined subgroups.

CONCLUSION

Extended-release niacin/laropiprant represents an effective therapeutic option for the treatment of dyslipidemia across a range of patient types.

The Bile Acid Sequestrant Acceptability scale validation study

AIMS

The primary objective of this study was to validate a novel Bile Acid Sequestrant Acceptability (BASA) Scale intended to assess the acceptability and/or tolerability of bile acid sequestrant (BAS) beverage preparations. A secondary objective was to assess the utility of weightings based on subjective clinical importance for the BASA scale individual components and its composite score.

METHODS

This was a randomised, single-blind, single site, controlled study of oral administration of 4 g of orange-flavoured generic cholestyramine powder, 12 g of orange-flavoured generic cholestyramine powder and an orange-flavoured sweetened control drink powder, each mixed with water.

RESULTS

The study sample included 42 subjects; 26 men and 16 women. Participants were non-Hispanic white (76.2%) or black/African American (23.8%), with a mean age of 51.4 years and body mass index of 30.1 kg/m(2). The components of the BASA scale were taste, texture, appearance and mixability; the possible total BASA scores ranged being 4-20; the higher the BASA scale score, the better the acceptability/tolerability. Composite BASA scale scores were significantly lower for the 4 g (mean BASA score = 10.3) and 12 g (mean BASA score = 9.4) cholestyramine compared with the control drink powder (mean BASA score = 16.7) (p < 0.001). BASA scale scores did not significantly differ between the 4 and 12 g of cholestyramine. (p = 0.215). Weighting of the components did not materially alter the results. Findings for the individual components of the BASA scale were similar to the composite values.

CONCLUSION

The BASA scale effectively distinguished between an orange-flavoured BAS powder and a commercial orange-flavour control powder.

Nicotinic acid- and monomethyl fumarate-induced flushing involves GPR109A expressed by keratinocytes and COX-2-dependent prostanoid formation in mice

The antidyslipidemic drug nicotinic acid and the antipsoriatic drug monomethyl fumarate induce cutaneous flushing through activation of G protein-coupled receptor 109A (GPR109A). Flushing is a troublesome side effect of nicotinic acid, but may be a direct reflection of the wanted effects of monomethyl fumarate. Here we analyzed the mechanisms underlying GPR109A-mediated flushing and show that both Langerhans cells and keratinocytes express GPR109A in mice. Using cell ablation approaches and transgenic cell type-specific GPR109A expression in Gpr109a-/- mice, we have provided evidence that the early phase of flushing depends on GPR109A expressed on Langerhans cells, whereas the late phase is mediated by GPR109A expressed on keratinocytes. Interestingly, the first phase of flushing was blocked by a selective cyclooxygenase-1 (COX-1) inhibitor, and the late phase was sensitive to a selective COX-2 inhibitor. Both monomethyl fumarate and nicotinic acid induced PGE2 formation in isolated keratinocytes through activation of GPR109A and COX-2. Thus, the early and late phases of the GPR109A-mediated cutaneous flushing reaction involve different epidermal cell types and prostanoid-forming enzymes. These data will help to guide new efficient approaches to mitigate nicotinic acid-induced flushing and may help to exploit the potential antipsoriatic effects of GPR109A agonists in the skin.

Clinical implications of the BARI 2D and COURAGE trials of coronary artery disease

The results of the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) and Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) clinical trials raise important questions about the prevention and treatment of coronary heart disease among type 2 diabetics and nondiabetics. The BARI 2D and COURAGE trials showed that pharmacological therapy is as effective as surgery or angioplasty, because of the incidence of total mortality and cardiovascular disease events. The results are consistent with the clinical trials of lipid-lowering, antihypertensive therapy. The efficacy of lowering glycohemoglobin below 7% or benefits of specific glucose-lowering drugs is still unresolved. The BARI 2D trial focused on more advanced atherosclerotic disease. An important question is whether newly incident diabetics should be screened for subclinical atherosclerosis and treated aggressively with pharmacological therapy as in the BARI 2D trial. We are still uncertain whether raising high-density lipoprotein cholesterol will provide further benefit in reducing coronary heart disease. Better measurement of plaque morphology, determinants of hypercoagulable status, and drugs to reduce thrombosis and plaque are of high priority. Longer follow-up of the BARI 2D and COURAGE trials will provide important information about the risks of cardiovascular disease events and disability. It will be important but difficult to translate the results of the trials to community practice under the current health care system.

Critical appraisal of laropiprant and extended-release niacin combination in the management of mixed dyslipidemias and primary hypercholesterolemia

Niacin is a B-complex vitamin which has been used for decades for the management of mixed dyslipidemias and primary hypercholesterolemia. It decreases the risk of cardiovascular events either when used as a monotherapy or in combination with other lipid lowering medications. However, a major limitation to its use is niacin-induced flushing occurring even with the extended-release formulations. Laropiprant, a selective prostaglandin-2 receptor inhibitor, specifically targets the cascade of events causing the flushing. It has been recently used in combination with extended-release niacin. This article will review the early experience with this combination with focus on efficacy, safety, tolerability and current place in therapy. Early data are promising and suggest that more patients in clinical practice will benefit from niacin combined with laropiprant. Ongoing clinical trials will provide a better insight on the long-term safety of the drug and its efficacy for reducing cardiovascular events.