Statin/fibrate combination in patients with metabolic syndrome or diabetes: evaluating the risks of pharmacokinetic drug interactions

Statin alternatives for the treatment of hypercholesterolemia - a safety evaluation

INTRODUCTION

Statins are well established as the first-line treatment to reduce low-density-lipoprotein cholesterol (LDL-C) and cardiovascular (CV) events, but some patients are unable to tolerate effective doses or sometimes any dose of statins and alternative treatments may be required.

AREAS COVERED

In this review we summarize the relevant published literature obtained from a PubMed search on the safety of statin alternatives for the treatment of hypercholesterolemia.

EXPERT OPINION

The main alternatives to statins are ezetimibe, the proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, evolocumab, alirocumab, and inclisiran, and the recently approved bempedoic acid. These have all shown an excellent safety profile and have not been associated with skeletal muscle symptoms or with increased risk of new onset diabetes and they have no major drug interactions. The injectable PCSK9 inhibitors are associated with a small increase in injection site reactions which are usually of mild or moderate intensity. Bempedoic acid is associated with a small increase in plasma uric acid and slightly increased frequency of episodes of gout in susceptible subjects. The cost and availability and the degree of lowering of LDL-C required are more likely to determine the choice of statin alternatives than the safety issues.

Efficacy and Safety of Fenofibrate-Statin Combination Therapy in Patients With Inadequately Controlled Triglyceride Levels Despite Previous Statin Monotherapy: A Multicenter, Randomized, Double-blind, Phase IV Study

PURPOSE

Residual cardiovascular risk reduction by fenofibrate in patients with high serum triglyceride (TG) levels despite previous statin monotherapy is not well characterized. The purpose of this study was to evaluate the efficacy and safety of a combination of choline fenofibrate and statin in patients with inadequately controlled TG levels despite previous statin monotherapy.

METHODS

This prospective, multicenter, randomized, double-blind study was conducted in Korea. A total of 133 patients with controlled LDL-C but elevated TG levels, already receiving statin monotherapy, were enrolled in the study, which was conducted from July 2018 to December 2019. Patients were randomly assigned to receive combination therapy with choline fenofibrate and statin or statin monotherapy in a 1:1 ratio. After 8 weeks of treatment, the lipid profiles and safety parameters of the patients in the 2 groups were compared.

FINDINGS

The study included 127 patients (64 in the combination group and 63 in the control group) older than 19 years. After 8 weeks of therapy, mean serum TG levels significantly decreased from 269.8 to 145.5 mg/dL (P < 0.0001) in the combination therapy group, whereas no significant changes occurred in the statin monotherapy group (from 271.1 to 280.5 mg/dL). Contrarily, the mean serum HDLC levels significantly increased from 45.0 to 50.4 mg/dL (P = 0.0004) in the combination therapy group, whereas there were no significant changes in the monotherapy group (from 44.3 to 44.7 mg/dL). There were no additional serious adverse events in the combination therapy group compared with the statin monotherapy group.

IMPLICATIONS

The combination therapy using choline fenofibrate and statin was found to be effective in serum TG control and likely tolerable in patients with high TG levels despite statin monotherapy. A larger study, conducted for a longer duration, is needed to evaluate the effectiveness of this combination in reducing cardiovascular risk. ClinicalTrials.gov identifier: NCT03874260.

Drug-drug-gene interactions as mediators of adverse drug reactions to diclofenac and statins: a case report and literature review

Concomitant treatment with drugs that inhibit drug metabolising enzymes and/or transporters, such as commonly prescribed statins and nonsteroidal anti-inflammatory drugs (NSAIDs), has been associated with prolonged drug exposure and increased risk of adverse drug reactions (ADRs) due to drug-drug interactions. The risk is further increased in patients with chronic diseases/comorbidities who are more susceptible because of their genetic setup or external factors. In that light, we present a case of a 46-year-old woman who had been experiencing acute renal and hepatic injury and myalgia over two years of concomitant treatment with diclofenac, atorvastatin, simvastatin/fenofibrate, and several other drugs, including pantoprazole and furosemide. Our pharmacogenomic findings supported the suspicion that ADRs, most notably the multi-organ toxicity experienced by our patient, may be owed to drug-drug-gene interactions and increased bioavailability of the prescribed drugs due to slower detoxification capacity and decreased hepatic and renal elimination. We also discuss the importance of CYP polymorphisms in the biotransformation of endogenous substrates such as arachidonic acid and their modulating role in pathophysiological processes. Yet even though the risks of ADRs related to the above mentioned drugs are substantially evidenced in literature, pre-emptive pharmacogenetic analysis has not yet found its way into common clinical practice.

Efficacy and safety of add on therapies in patients with hypercholesterolemia undergoing statin therapy

INTRODUCTION

Statins are the first-line treatment to reduce cardiovascular (CV) events, mainly by reducing low-density-lipoprotein cholesterol (LDL-C), but many patients need additional treatments to reach the current lipid goals.

AREAS COVERED

Herein, the authors review the published literature on the efficacy and safety of the therapies that are most often added to statins to achieve lipid targets.

EXPERT OPINION

Ezetimibe is usually the first additional treatment to achieve LDL-C targets. It reduces LDL-C by about a further 20% and has an excellent safety and tolerability profile. The monoclonal antibody proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, evolocumab, and alirocumab, can reduce LDL-C by ≥50% when added to statins and they also have a well-established safety and tolerability record. The recently approved bempedoic acid is well tolerated and appears to be free of skeletal muscle-related problems, but the CV outcome study with this drug has not been completed. Inclisiran, a small-interfering RNA targeting PCSK9 is at an advanced stage of development and the available data indicate a satisfactory safety profile and LDL-C lowering efficacy similar to the PCSK9 monoclonal antibodies with the advantage of less frequent administration.

Targeting apoC-III and ANGPTL3 in the treatment of hypertriglyceridemia

INTRODUCTION

The prevalence of hypertriglyceridemia (HTG) is increasing. Elevated triglyceride (TG) levels are associated with an increased cardiovascular disease (CVD) risk. Moreover, severe HTG results in an elevated risk of pancreatitis, especially in severe HTG with an up to 350-fold increased risk. Both problems emphasize the clinical need for effective TG lowering.

AREAS COVERED

The purpose of this review is to discuss the currently available therapies and to elaborate the most promising novel therapeutics for TG lowering.

EXPERT OPINION

Conventional lipid lowering strategies do not efficiently lower plasma TG levels, leaving a residual CVD and pancreatitis risk. Both apolipoprotein C-III (apoC-III) and angiopoietin-like 3 (ANGPTL3) are important regulators in TG-rich lipoprotein (TRL) metabolism. Several novel agents targeting these linchpins have ended phase II/III trials. Volanesorsen targeting apoC-III has shown reductions in plasma TG levels up to 90%. Multiple ANGPLT3 inhibitors (evinacumab, IONIS-ANGPTL3-L_Rx, ARO-ANG3) effectuate TG reductions up to 70% with concomitant potent reduction in all other apoB containing lipoprotein fractions. We expect these therapeutics to become players in the treatment for (especially) severe HTG in the near future.

Pharmacokinetics of current and emerging treatments for hypercholesterolemia

Introduction: Reduction of low-density-lipoprotein cholesterol (LDL-C) and other apolipoprotein B (apoB)-containing lipoproteins reduces cardiovascular (CV) events and greater reductions have greater benefits. Current lipid treatments cannot always achieve desirable LDL-C targets and additional or alternative treatments are often needed.Areas covered: In this article, we review the pharmacokinetics of the available and emerging treatments for hypercholesterolemia and focus on recently approved drugs and those at a late stage of development.Expert opinion: Statin pharmacokinetics are well known and appropriate drugs and doses can usually be chosen for individual patients to achieve LDL-C targets and avoid adverse effects and drug-drug interactions. Ezetimibe, icosapent ethyl and the monoclonal antibodies evolocumab and alirocumab have established efficacy and safety. Newer oral agents including pemafibrate and bempedoic acid have generally favorable pharmacokinetics supporting use in a wide range of patients. RNA-based therapies with antisense oligonucleotides are highly specific for their targets and those inhibiting apoB, apoCIII, angiopoietin-like protein 3 and lipoprotein(a) have shown promising results. The small-interfering RNA inclisiran has the notable advantage that a single subcutaneous administration may be effective for up to 6 months. The CV outcome trial results and long term safety data are eagerly awaited for these new agents.

Investigational drugs in development for hypertriglyceridemia: a coming-of-age story

Introduction: Elevated triglyceride (TG) level is a prevalent condition in the general population and in patients with cardiovascular (CV) risk even under statin therapy. Severe hypertriglyceridemia (HTG) puts patients at risk for acute pancreatitis. Several TG-lowering drugs failed in clinical trials, but subgroup analyses suggest that high-risk patients, such as those with atherogenic dyslipidemia or diabetes, benefit from TG lowering.Areas covered: We review advances for TG-lowering drugs in clinical development. These include selective PPARα modulators, omega-3 fatty acid formulations that have been approved for severe HTG, and inhibitors of apolipoprotein C-III, angiopoietin-like-3 or microsomal transfer protein. Lessons learned from the success of the phase 3 trial REDUCE-IT with high-dose icosapent ethyl are also reviewed.Expert opinion: We believe that TG-lowering therapies are coming of age as they will allow to treat patients with high CV risk and moderate HTG, including T2D subjects, as well as patients with severe HTG or even homozygous familial hypercholesterolemia, all of which being 'optimally' treated with a statin. More studies on the impact of therapy on quality of life in patients with severe HTG should be conducted with the help of patient registries.

Pravastatin and Gemfibrozil Modulate Differently Hepatic and Colonic Mitochondrial Respiration in Tissue Homogenates from Healthy Rats

Statins and fibrates are widely used for the management of hypertriglyceridemia but they also have limitations, mostly due to pharmacokinetic interactions or side effects. It is conceivable that some adverse events like liver dysfunction or gastrointestinal discomfort are caused by mitochondrial dysfunction. Data about the effects of statins and fibrates on mitochondrial function in different organs are inconsistent and partially contradictory. The aim of this study was to investigate the effect of pravastatin (statin) and gemfibrozil (fibrate) on hepatic and colonic mitochondrial respiration in tissue homogenates. Mitochondrial oxygen consumption was determined in colon and liver homogenates from 48 healthy rats after incubation with pravastatin or gemfibrozil (100, 300, 1000 μM). State 2 (substrate dependent respiration) and state 3 (adenosine diphosphate: ADP-dependent respiration) were assessed. RCI (respiratory control index)—an indicator for coupling between electron transport chain system (ETS) and oxidative phosphorylation (OXPHOS) and ADP/O ratio—a parameter for the efficacy of OXPHOS, was calculated. Data were presented as a percentage of control (Kruskal–Wallis + Dunn’s correction). In the liver both drugs reduced state 3 and RCI, gemfibrozil-reduced ADP/O (complex I). In the colon both drugs reduced state 3 but enhanced ADP/O. Pravastatin at high concentration (1000 µM) decreased RCI (complex II). Pravastatin and gemfibrozil decrease hepatic but increase colonic mitochondrial respiration in tissue homogenates from healthy rats.

The selective peroxisome proliferator-activated receptor alpha modulator (SPPARMα) paradigm: conceptual framework and therapeutic potential : A consensus statement from the International Atherosclerosis Society (IAS) and the Residual Risk Reduction Initiative (R3i) Foundation

In the era of precision medicine, treatments that target specific modifiable characteristics of high-risk patients have the potential to lower further the residual risk of atherosclerotic cardiovascular events. Correction of atherogenic dyslipidemia, however, remains a major unmet clinical need. Elevated plasma triglycerides, with or without low levels of high-density lipoprotein cholesterol (HDL-C), offer a key modifiable component of this common dyslipidemia, especially in insulin resistant conditions such as type 2 diabetes mellitus. The development of selective peroxisome proliferator-activated receptor alpha modulators (SPPARMα) offers an approach to address this treatment gap. This Joint Consensus Panel appraised evidence for the first SPPARMα agonist and concluded that this agent represents a novel therapeutic class, distinct from fibrates, based on pharmacological activity, and, importantly, a safe hepatic and renal profile. The ongoing PROMINENT cardiovascular outcomes trial is testing in 10,000 patients with type 2 diabetes mellitus, elevated triglycerides, and low levels of HDL-C whether treatment with this SPPARMα agonist safely reduces residual cardiovascular risk.

Peroxisome proliferator-activated receptor alpha-mediated drug toxicity in the liver

INTRODUCTION

Drug-induced hepatic injury is the most common cause of acute liver failure in the United States. Peroxisome proliferator-activated receptor alpha (PPARα)-mediated drugs are included among the approximately 900 natural and synthetic substances, which have shown hepatotoxicity. Areas covered: This review will focus on fibrates - PPARα agonists and their implication in causing liver injury. Expert opinion: Compelling evidence for fibrate-induced hepatotoxicity is not available. Results have been varying because several large randomized clinical trials have reported similar elevations of plasma transaminase levels in fibrate or placebo treated groups. On the other hand, one meta-analysis has reported an increased risk of hepatotoxicity when fibrates are combined with statins. Fibrate induced clinically apparent liver damage has been demonstrated in case reports. However, there is a wide spectrum of clinical phenotypic presentations of these cases (onset of injury, pattern of enzyme elevation and resolution of the symptoms), which reduces the ability to identify specific cause and effect of any putative fibrate-induced hepatotoxicity. Thus, the current recommendations for using fibrates include monitoring of aminotransferase levels especially if combined with statins and discontinuation of the treatment only if the levels persist above three times the upper limit of normal.

1H NMR-based metabolomics reveals sub-lethal toxicity of a mixture of diabetic and lipid-regulating pharmaceuticals on amphibian larvae

Pharmaceuticals are widely used for the treatment of various physical and psychological ailments. Due to incomplete removal during sewage treatment many pharmaceuticals are frequently detected in aquatic waterways at trace concentrations. The diversity of pharmaceutical contaminants and potential for complex mixtures to occur makes it very difficult to predict the toxicity of these compounds on wildlife, and robust methods are therefore needed to explore sub-lethal effects. Metabolic syndrome is one of the most widespread health concerns currently facing the human population, and various drugs, including anti-diabetic medications and lipid- and cholesterol-lowering fibrates and statins, are widely prescribed as treatment. In this study, we exposed striped marsh frog (Limnodynastes peronii) tadpoles to a mixture of the drugs metformin, atorvastatin and bezafibrate at 0.5, 5, 50 and 500μg/L to explore possible effects on growth and development, energy reserves (triglycerides and cholesterol), and profiles of small polar metabolites extracted from hepatic tissues. It was hypothesised that exposure would result in a general reduction in energy reserves, and that this would subsequently correspond with reduced growth and development. Responses differed from expected outcomes based on the known mechanisms of these compounds in humans, with no changes to hepatic triglycerides or cholesterol and a general increase in mass and condition with increasing exposure concentration. Deviation from the expected response patterns may be explained by differences in the receptivity or uptake of the compounds in non-mammalian species. Proton nuclear magnetic resonance (¹H NMR) spectroscopy revealed evidence of broad metabolic dysregulation in exposed animals, and possible interaction between the solvent and mixture. Specifically, increased lactic acid and branched-chain amino acids were observed, with responses tending to follow a non-monotonic pattern. Overall, results demonstrate that a mixture of drugs commonly prescribed to treat human metabolic syndrome is capable of eliciting physiological and developmental effects on larval amphibians. Importantly, outcomes further suggest that it may not be possible to predict toxicological effects in non-target wildlife based on our knowledge of how these compounds act in humans.

Comparison of efficacy and safety of choline fenofibrate (fenofibric acid) to micronized fenofibrate in patients of mixed dyslipidemia: A randomized, open-label, multicenter clinical trial in Indian population

INTRODUCTION

Choline fenofibrate is a newly developed choline salt of fenofibric acid, which is more hydrophilic than fenofibrate. This study was initiated to evaluate the safety and efficacy of choline fenofibrate in comparison to micronized fenofibrate among Indian patients of mixed dyslipidemia.

METHODS

A multicenter, open-label, randomized, active controlled, comparative, parallel group study was conducted at around 10 centers spread all across the country. Mixed dyslipidemia patients (serum triglycerides [TG] levels between 150 and 500 mg/dl), aged 18-70 years and taking stable statin dose for 8 weeks were randomized to choline fenofibrate 135 mg delayed release tablets and micronized fenofibrate 160 mg tablets once daily for 12 weeks. The primary endpoint of the study was percentage change in serum TG level at the end of 12 weeks.

RESULTS

A total of 226 patients were enrolled in this study, of which 116 patients were administered choline fenofibrate and 110 patients were administered micronized fenofibrate. At the end of 12 weeks, there was a significant reduction in TG level (34.24% in choline fenofibrate group and 38.13% reduction in micronized fenofibrate group). However, the difference between group was not statistically different (P = 0.471). Similarly, there was a significant increase in high-density lipoprotein cholesterol at the end of 12 weeks (10% increase in choline fenofibrate group and 9% increase in micronized fenofibrate group); but the difference between the group was not statistically significant (P = 0.598). Both the treatment was safe and well tolerated.

CONCLUSION

Choline fenofibrate delayed release 135 mg is as safe and effective as 160 mg of micronized fenofibrate in Indian patients with mixed dyslipidemia.

Drug-drug interactions that interfere with statin metabolism

INTRODUCTION

Lipid-lowering drugs, especially hydroxymethylglutaryl-CoA reductase inhibitors (statins), are widely used in the treatment and prevention of atherosclerotic diseases. The benefits of statins are well documented. However, myotoxic side effects, which can sometimes be severe, including myopathy or rhabdomyolysis, have been associated with the use of statins. In some cases, this toxicity is associated with pharmacokinetic alterations. Potent inhibitors of CYP 3A4 significantly increase plasma concentrations of the active forms of simvastatin, lovastatin and atorvastatin. Fluvastatin is metabolized by CYP2C9, while pravastatin, rosuvastatin and pitavastatin are not susceptible to inhibition by any CYP.

AREAS COVERED

This review discusses the pharmacokinetic aspects of the drug-drug interaction with statins and genetic polymorphisms in CYPs, which are involved in the metabolism of statins, and highlights the importance of establishing a system utilizing electronic medical information practically to avoid adverse drug reactions.

EXPERT OPINION

An understanding of the mechanisms underlying statin interactions will help to minimize drug interactions and develop statins that are less prone to adverse interactions. Quantitatively analyzed information for the low-density lipoprotein cholesterol lowering effects of statin based on electronic medical records may be useful for avoiding the adverse effect of statins.

Meta-analysis of safety of the coadministration of statin with fenofibrate in patients with combined hyperlipidemia

Addition of fenofibrate to statin therapy might represent a viable treatment option for patients whose high risk for coronary heart disease is not controlled by a statin alone. However, safety of coadministration of statin with fenofibrate has been a great concern. The present study tested the safety of coadministration of statin with fenofibrate. We systematically searched the literature to identify randomized controlled trials examining safety of coadministration of statin with fenofibrate. A meta-analysis was performed to estimate safety of coadministration of statin with fenofibrate using fixed-effects models. There were 1,628 subjects in the identified 6 studies. Discontinuation attributed to any adverse events (4.5% vs 3.1%, p = 0.20), any adverse events (42% vs 41%, p = 0.82), adverse events related to study drug (10.9% vs 11.0%, p = 0.95), and serious adverse events (2.0% vs 1.5%, p = 0.71) were not significantly different in the 2 arms. Incidence of alanine aminotransferase and/or aspartate aminotransferase ≥3 times upper limit of normal in the combination therapy arm was significantly higher than in the statin monotherapy arm (3.1% vs 0.2%, p = 0.0009). In the 6 trials with 1,628 subjects no case of myopathy or rhabdomyolysis was reported. In conclusion, statin-fenofibrate combination therapy was tolerated as well as statin monotherapy. Physicians should consider statin-fenofibrate combination therapy to treat patients with mixed dyslipidemia.

A review of time courses and predictors of lipid changes with fenofibric acid-statin combination

Fibrates activate peroxisome proliferator activated receptor α and exert beneficial effects on triglycerides, high-density lipoprotein cholesterol, and low density lipoprotein subspecies. Fenofibric acid (FA) has been studied in a large number of patients with mixed dyslipidemia, combined with a low- or moderate-dose statin. The combination of FA with simvastatin, atorvastatin and rosuvastatin resulted in greater improvement of the overall lipid profile compared with the corresponding statin dose. The long-term efficacy of FA combined with low- or moderate- dose statin has been demonstrated in a wide range of patients, including patients with type 2 diabetes mellitus, metabolic syndrome, or elderly subjects. The FA and statin combination seems to be a reasonable option to further reduce cardiovascular risk in high-risk populations, although trials examining cardiovascular disease events are missing.

Fenofibrate: a review of its use in dyslipidaemia

Fenofibrate is a fibric acid derivative indicated for the treatment of severe hypertriglyceridaemia and mixed dyslipidaemia in patients who have not responded to nonpharmacological therapies. The lipid-modifying effects of fenofibrate are mediated by the activation of peroxisome proliferator-activated receptor-α. Fenofibrate also has nonlipid, pleiotropic effects (e.g. reducing levels of fibrinogen, C-reactive protein and various pro-inflammatory markers, and improving flow-mediated dilatation) that may contribute to its clinical efficacy, particularly in terms of improving microvascular outcomes. Fenofibrate improves the lipid profile (particularly triglyceride [TG] and high-density lipoprotein-cholesterol [HDL-C] levels) in patients with dyslipidaemia. Compared with statin monotherapy, fenofibrate monotherapy tends to improve TG and HDL-C levels to a significantly greater extent, whereas statins improve low-density lipoprotein-cholesterol (LDL-C) and total cholesterol levels to a significantly greater extent. Fenofibrate is also associated with promoting a shift from small, dense, atherogenic LDL particles to larger, less dense LDL particles. Combination therapy with a statin plus fenofibrate generally improves the lipid profile to a greater extent than monotherapy with either agent in patients with dyslipidaemia and/or type 2 diabetes mellitus or the metabolic syndrome. In the pivotal FIELD and ACCORD trials in patients with type 2 diabetes, fenofibrate did not significantly reduce the risk of coronary heart disease events to a greater extent than placebo, and simvastatin plus fenofibrate did not significantly reduce the risk of major cardiovascular (CV) events to a greater extent than simvastatin plus placebo. However, the risk of some nonfatal macrovascular events and the incidence of certain microvascular outcomes were reduced significantly more with fenofibrate than with placebo in the FIELD trial, and in the ACCORD trial, patients receiving simvastatin plus fenofibrate were less likely to experience progression of diabetic retinopathy than those receiving simvastatin plus placebo. Subgroup analyses in the FIELD and ACCORD Lipid trials indicate that fenofibrate is of the greatest benefit in decreasing CV events in patients with atherogenic dyslipidaemia. Fenofibrate is generally well tolerated when administered alone or in combination with a statin. Thus, in patients with dyslipidaemia, particularly atherogenic dyslipidaemia, fenofibrate is a useful treatment option either alone or in combination with a statin.

Cytochrome P450-mediated cardiovascular drug interactions

INTRODUCTION

There are numerous drug-drug interactions (DDIs) related to cardiovascular medications and many of these are mediated via the cytochrome P450 (CYP) system. Some of these may lead to serious adverse events and it is, therefore, essential that clinicians are aware of the important interactions that occur.

AREAS COVERED

An extensive literature search was performed to analyze the CYP-mediated cardiovascular DDIs that lead to a loss of efficacy or potential toxicity. Cardiovascular drugs may be victims or act as perpetrators of DDIs. The paper analyzes CYP-mediated drug interactions concerning anticoagulants, antiplatelet agents, antiarrhythmics, β-blockers, calcium antagonists, antihypertensive medications, lipid-lowering drugs and oral antidiabetic agents.

EXPERT OPINION

Cardiovascular DDIs involving the CYP system are numerous. Additionally, the spectrum of drugs prescribed is constantly changing, particularly with cardiovascular diseases and it is not necessarily the case that drugs that had shown safety earlier will always show safety. Clinicians are encouraged to develop their knowledge of CYP-mediated DDIs so that they can choose safe drug combination regimens, adjust drug dosages appropriately and conduct therapeutic drug monitoring for drugs with narrow therapeutic indices.

Comparison of fibrate, ezetimibe, low- and high-dose statin therapy for the dyslipidemia of the metabolic syndrome in a mouse model

BACKGROUND AND AIM

The treatment-of-choice for the optimal management of the dyslipidemia of the metabolic syndrome (MetS) is not clearly defined. We compared the efficacy of 4 drug regimes for the management of this dyslipidemia in a mouse model.

MATERIALS AND METHODS

A total of 60 C57Bl6 mice comprised the study group. The first 10 received standard mouse food for the whole experiment (control group). The remaining 50 mice received atherogenic diet for 14 weeks until the development of the MetS. The mice were then divided into 5 groups: the 1st group continued receiving atherogenic diet, while the other 4 groups received atherogenic diet plus ezetimibe (10 mg/kg per day), fenofibrate (100 mg/kg per day), low-dose atorvastatin (10 mg/kg per day), or high-dose (40 mg/kg per day) atorvastatin, respectively, for another 8 weeks.

RESULTS

High-dose atorvastatin treatment achieved the best lipid profile compared with low-dose atorvastatin, ezetimibe, and fibrate therapy. The lipid profile of mice receiving atherogenic diet plus high-dose atorvastatin treatment was similar with mice on regular chow.

CONCLUSIONS

High-dose atorvastatin treatment resulted in optimization of the lipid profile in the presence of a high-fat atherogenic diet in a mouse model. Our results suggest that high-dose atorvastatin treatment may be the optimal treatment option for the dyslipidemia associated with MetS. Nevertheless, verification of these results in humans is required before any definite conclusions can be drawn.

The effect of fibrate-statin combination therapy on cardiovascular events: a retrospective cohort analysis

OBJECTIVE

To investigate the long-term efficacy of fibrate-statin combination therapy on cardiovascular events as opposed to lipid levels.

RESEARCH DESIGN AND METHODS

A retrospective analysis was performed of patients attending metabolic clinics. Cardiovascular risk factor, baseline and final lipid data and details of concomitant drug therapies were gathered on all subjects.

OUTCOME MEASURE

The occurrence of major adverse cardiovascular events (MACE) was recorded and major prognostic factors associated with outcome determined.

RESULTS

A total of 318 patients with mixed dyslipidaemia were identified on fibrate-statin therapy. Follow-up comprised an average of 7.5 years totalling 2400 patient-years. Patients were 78% male aged 62 years and 68% had evidence of previous cardiovascular disease (CVD). Smoking was present in 17%, hypertension in 41% and 32% had established diabetes. Baseline lipid parameters were total cholesterol (TC) 6.84 mmol/L, triglycerides (TG) 6.09 mmol/L and HDL-C 1.09 mmol/L. Fibrate-statin combination reduced TC by 27% to 4.64 mmol/L, TG by a median 42% to 2.33 mmol/L and increased HDL-C by 21% to 1.22 mmol/L. Non-HDL-C was reduced by 35% and apolipoprotein B by 17%. MACE occurred in 25%. Logistic regression analysis showed that patients with MACE had higher initial TC (7.02 vs. 6.80 mmol/L; p = 0.002), established CVD (65 vs. 57%; p = 0.05) and a lesser atherogenic index response (31 vs. 38%; p = 0.008). Cox regression analysis showed that age (p = 0.002), and previous CVD (p < 0.001) were determinants of outcome allied either to reduction in TG (p = 0.009), TC (p = 0.04) and increase in HDL-C (p = 0.05) or change in TG (p = 0.002) and non-HDL-C (p = 0.01).

CONCLUSION

Fibrate-statin therapy in a population with mixed dyslipidaemia resulted in an improved lipid profile with few side-effects. Consistent with its effects, decreases in TG allied with modest decrease in cholesterol and an increase in HDL-C, were associated with better prognosis.

Niacin and fibrates in atherogenic dyslipidemia: pharmacotherapy to reduce cardiovascular risk

Although statin therapy represents a cornerstone of cardiovascular disease (CVD) prevention, a major residual CVD risk (60-70% of total relative risk) remains, attributable to both modifiable and non-modifiable risk factors. Among the former, low levels of HDL-C together with elevated triglyceride (TG)-rich lipoproteins and their remnants represent major therapeutic targets. The current pandemic of obesity, metabolic syndrome, and type 2 diabetes is intimately associated with an atherogenic dyslipidemic phenotype featuring low HDL-C combined with elevated TG-rich lipoproteins and small dense LDL. In this context, there is renewed interest in pharmacotherapeutic strategies involving niacin and fibrates in monotherapy and in association with statins. This comprehensive, critical review of available data in dyslipidemic subjects indicates that niacin is more efficacious in raising HDL-C than fibrates, whereas niacin and fibrates reduce TG-rich lipoproteins and LDL comparably. Niacin is distinguished by its unique capacity to effectively lower Lp(a) levels. Several studies have demonstrated anti-atherosclerotic action for both niacin and fibrates. In contrast with statin therapy, the clinical benefit of fibrates appears limited to reduction of nonfatal myocardial infarction, whereas niacin (frequently associated with statins and/or other agents) exerts benefit across a wider range of cardiovascular endpoints in studies involving limited patient numbers. Clearly the future treatment of atherogenic dyslipidemias involving the lipid triad, as exemplified by the occurrence of the mixed dyslipidemic phenotype in metabolic syndrome, type 2 diabetes, renal, and auto-immune diseases, requires integrated pharmacotherapy targeted not only to proatherogenic particles, notably VLDL, IDL, LDL, and Lp(a), but also to atheroprotective HDL.

Interpreting clinical trials of diabetic dyslipidaemia: new insights

Current treatment guidelines highlight the importance of aggressive lipid-modifying therapy in reducing cardiovascular risk in patients with type 2 diabetes. Statins are established as the cornerstone of dyslipidaemia management in diabetic patients, based on their efficacy in lowering levels of low-density lipoprotein cholesterol (LDL-C). However, statins fail to address the high residual cardiovascular risk in treated patients, some of which may be attributable to low HDL cholesterol (HDL-C) and elevated triglycerides and to a preponderance of small, dense LDL particles, indicating the need for further intervention. Fibrates are effective against all components of atherogenic dyslipidaemia associated with type 2 diabetes. Clinical studies, most notably the Fenofibrate Intervention and Event Lowering in Diabetes, indicate that fibrates, most likely in combination with a statin, have a secondary role in reducing cardiovascular risk in patients with type 2 diabetes, particularly in those without prior cardiovascular disease or patients with low HDL-C. Results are awaited from the ongoing Action to Control Cardiovascular Risk in Diabetes trial to fully evaluate the outcome benefits of this combination strategy.

Efficacy and safety of ABT-335 (fenofibric acid) in combination with atorvastatin in patients with mixed dyslipidemia

In patients with mixed dyslipidemia characterized by increased triglycerides (TG), decreased high-density lipoprotein (HDL) cholesterol, and increased low-density lipoprotein (LDL) cholesterol, monotherapy with lipid-altering drugs often fails to achieve all lipid targets. This multicenter, double-blind, active-controlled study evaluated ABT-335 (fenofibric acid) in combination with 2 doses of atorvastatin in patients with mixed dyslipidemia. A total of 613 patients with LDL cholesterol > or =130 mg/dl, TG > or =150 mg/dl, and HDL cholesterol <40 mg/dl for men and <50 mg/dl for women were randomly assigned to ABT-335 (135 mg), atorvastatin (20, 40, or 80 mg), or combination therapy (ABT-335 + atorvastatin 20 or 40 mg) and treated for 12 weeks. Combination therapy with ABT-335 + atorvastatin 20 mg resulted in significantly greater improvements in TG (-45.6% vs -16.5%) and HDL cholesterol (14.0% vs 6.3%) compared with atorvastatin 20 mg and LDL cholesterol (-33.7% vs -3.4%) compared with ABT-335. Similarly, significantly greater improvements were observed with ABT-335 + atorvastatin 40 mg in TG (-42.1% vs -23.2%) and HDL cholesterol (12.6% vs 5.3%) compared with atorvastatin 40 mg and LDL cholesterol (-35.4% vs -3.4%) compared with ABT-335 monotherapy. Combination therapy also improved multiple secondary variables. Combination therapy was generally well tolerated with a safety profile consistent with those of ABT-335 and atorvastatin monotherapies. No rhabdomyolysis was reported. In conclusion, ABT-335 + atorvastatin combination therapy resulted in more effective control of multiple lipid parameters than either monotherapy and may be an appropriate therapy for patients with mixed dyslipidemia.

Combination statin-fibrate therapy: safety aspects

Patients with type 2 diabetes or metabolic syndrome remain at high residual risk of cardiovascular events even after intensive statin therapy. While treatment guidelines recommend the addition of a fibrate to statin therapy in this setting, concerns about the potential for myopathy may limit the use of this combination in clinical practice. These concerns are certainly justified for gemfibrozil, which interferes with statin glucuronidation, leading to elevation in statin plasma concentrations and an increased risk of myotoxicity in combination with a range of commonly prescribed statins. However, the available evidence refutes suggestions that this is a class effect for fibrates. Fenofibrate does not adversely influence the metabolism or pharmacokinetics of any of the commonly prescribed statins. This in turn translates to a reduced potential for myotoxicity in combination with a statin. Data are awaited from the ongoing Action to Control Cardiovascular Risk in Diabetes (ACCORD) study to evaluate the efficacy and safety of fenofibrate plus simvastatin combination therapy in type 2 diabetes patients.

A review of the current status of the management of mixed dyslipidemia associated with diabetes mellitus and metabolic syndrome

Current treatment guidelines recommend lowering elevated low-density lipoprotein (LDL) cholesterol levels with a statin as the primary lipid-modifying intervention to reduce cardiovascular risk in patients with type 2 diabetes mellitus or metabolic syndrome. However, even with high-dose statin therapy or the combination of statin plus ezetimibe, many patients remain at substantial risk of a cardiovascular event. Increasingly, there is recognition of the importance of treating all components of the atherogenic dyslipidemic profile associated with both conditions, specifically low high-density lipoprotein cholesterol and elevated triglyceride levels, in addition to lowering LDL cholesterol. Both niacin (nicotinic acid) and fibrates are recommended as options for combination with a statin in this setting. Data from ongoing prospective outcomes studies are needed to evaluate the efficacy and safety of these combinations.

Lipid lowering in the patients with prediabetes/metabolic syndrome: what is the evidence?

PURPOSE OF REVIEW

Both the metabolic syndrome and prediabetes are associated with increased coronary risk. Lipoprotein abnormalities are among the many factors that may contribute to this. The present review focuses on these abnormalities and the evidence indicating that correcting them may reduce the risk.

RECENT FINDINGS

Many drugs, both old and in development, may be able to correct lipoprotein abnormalities. No clinical trials are specifically designed to examine the effects of lipid intervention on coronary risk in the metabolic syndrome. Data from subgroup analyses and extrapolation from studies in those with and without diabetes have led to recommendations about the benefits and the targets for lipoprotein treatment.

SUMMARY

The primary goal of lipoprotein treatment is to bring the LDL-C to target levels. Thereafter, if plasma triglycerides are high and HDL-C is low, these should be corrected.

Concomitant use of statins and CYP3A4 inhibitors in administrative claims and electronic medical records databases

BACKGROUND

Patients may experience increased risk of adverse drug interactions when statins are administered concomitantly with cytochrome P450 3A4 (CYP3A4) inhibitors.

OBJECTIVE

To determine patient numbers in routine clinical practice with concomitant exposure to CYP3A4-metabolized statins and CYP3A4 inhibitors and highlight potential risk for adverse drug interaction.

METHODS

Exposure to prescription medications over 1 year (2005-2006) was evaluated from patient records: US PharMetrics Integrated Patient-Centric administrative claims database and the US General Electric Medical System (GEMS) database. Rates of concomitant prescribing of statins with CYP3A4 inhibitors (listed in United States of America product labels and all identified potential inhibitors) were examined in the cohort overall, in those aged ≥65 years, and in those receiving higher doses of statins.

RESULTS

Overall, 951,166 patient records were included (PharMetrics n = 650,825; GEMS, n = 300,341). Of these, 792,081 (83%) patients used a CYP3A4-metabolized statin as opposed to a non-CYP3A4-metabolized statin (17%). Findings from both databases were consistent. Overall, 25-30% of patients given a CYP3A4-metabolized statin were concomitantly exposed to a CYP3A4 inhibitor, including approximately 9% concomitantly exposed to a labeled inhibitor, findings consistent with those in patients aged ≥65 years, and patients on higher doses of statins.

CONCLUSIONS

Clinicians frequently co-prescribe CYP3A4-metabolized statins with CYP3A4 inhibitors. Physician education regarding the impact of these inhibitors on the metabolism of lovastatin, simvastatin, and atrovastatin is needed. Further studies are also needed to determine whether concomitant administration of a non-CYP3A4-metabolized statin (such as fluvastatin, pravastatin, or rosuvastatin) with a CYP3A4 inhibitor, may reduce adverse event rates in routine clinical practice.

PPAR-alpha: therapeutic role in diabetes-related cardiovascular disease

Among individuals with diabetes mellitus, cardiovascular disease remains the leading cause of death, despite the many treatment modalities that have been developed over time. The PPAR family, including PPAR-alpha, play important roles in glucose and lipid metabolism and atherosclerosis and thus are potential therapeutic targets. Fibrates act upon PPAR-alpha and appear to target the typical dyslipidaemia of diabetes. Several large prospective clinical trials have shown both primary prevention and secondary prevention benefit with fibrates, although they only had small subgroups of patients with diabetes. The first large outcome study to exclusively study those with diabetes was the FIELD study, which showed no reduction in the primary cardiovascular end-point and only some benefit in the secondary end-point. There are many potential explanations for these results; however, it would appear that at present, there is no role for fibrates as monotherapy for the reduction of cardiovascular risk among those with diabetes. However, their potential role in combination with statin therapy remains to be further elucidated with ongoing studies.

A practical "ABCDE" approach to the metabolic syndrome

The metabolic syndrome comprises a cluster of risk factors for cardiovascular disease and type 2 diabetes mellitus that are due to abdominal obesity and insulin resistance. This increasingly important proinflammatory condition remains both underrecognized and undertreated. To aid physicians in their approach to the metabolic syndrome, we assessed and synthesized the literature on cardiovascular risk assessment and early intervention for risk reduction. We performed a comprehensive search of MEDLINE and the Cochrane database for peer-reviewed clinical studies published from January 1, 1988, to December 31, 2007, augmented by consultation with content experts. We used the search terms metabolic syndrome, abdominal obesity, waist circumference, insulin resistance, cardiovascular disease, prediabetes, diabetes, treatment, prevention, aspirin, hypertension, cholesterol, atherogenic dyslipidemia, lifestyle therapy, diet, and exercise. Criteria used for study review were controlled study design, English language, relevance to clinicians, and validity based on experimental design and appropriateness of conclusions. Although growing evidence supports early intervention in patients with the metabolic syndrome, many physicians do not recognize the risk associated with this condition and fail to initiate early treatment. A comprehensive management plan can be assembled through an "ABCDE" approach: "A" for assessment of cardiovascular risk and aspirin therapy, "B" for blood pressure control, "C" for cholesterol management, "D" for diabetes prevention and diet therapy, and "E" for exercise therapy. This ABCDE approach provides a practical and systematic framework for encouraging metabolic syndrome recognition and for implementing a comprehensive, evidence-based management plan for the reduction of cardiovascular risk.

Do people with diabetes need statins?

The prevalence of type 2 diabetes mellitus continues to increase rapidly. Persons with diabetes face a 2-fold greater absolute risk of cardiovascular disease (CVD) than those without diabetes. Many diabetic patients die before reaching the hospital after a cardiovascular event. Use of statin therapy for intensive control of diabetic dyslipidemia has produced relative reductions in CVD risk of about 25% in randomized, controlled clinical trials. This is true even though low-density lipoprotein cholesterol, the primary target of statin therapy, might not be markedly elevated in diabetic patients. Most patients with diabetes or diabetes plus established CVD warrant intensive statin therapy. Statin therapy has the ability to achieve low-density lipoprotein cholesterol goals recommended in treatment guidelines. Alone or in combination with an additional lipid-lowering drug, statins may also improve triglyceride and high-density lipoprotein cholesterol abnormalities in patients with diabetes.

Lipid-lowering therapy in patients with type 2 diabetes: the case for early intervention

Chronic complications of type 2 diabetes, in particular, macrovascular complications, confer substantial morbidity and mortality and adversely affect a patient's quality of life. Early intensive intervention to control cardiovascular risk factors is essential in clinical management. Atherogenic dyslipidaemia characterized by elevated triglycerides, a low level of high-density lipoprotein cholesterol (HDL-C), and an increase in the preponderance of small, dense low-density lipoprotein (LDL) particles, is a key modifiable risk factor for macrovascular diabetic complications. Lowering low-density lipoprotein cholesterol (LDL-C) with a statin (or the combination of statin and ezetimibe) is the main focus for reducing cardiovascular risk in patients with diabetes. However, statins fail to address the residual cardiovascular risk associated with low HDL-C. Fibrates are effective against all components of the atherogenic dyslipidaemia associated with type 2 diabetes. Secondary analyses of the Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) study suggest a role for early treatment with fenofibrate in improving cardiovascular risk reduction in type 2 diabetes and provide safety data supporting the use of fenofibrate in combination with a statin. Data from the FIELD study suggest that fenofibrate may also have potential to impact on microvascular diabetic complications associated with type 2 diabetes. Data are awaited from the ongoing Action to Control Cardiovascular Risk in Diabetes (ACCORD) study to evaluate the outcome benefits of combining fenofibrate with a statin in patients with type 2 diabetes. Finally, in view of divergent study results and outstanding data, assessment of the risk of the individual with type 2 diabetes is mandatory to assist clinical decision-making when initiating lipid therapy.

Confronting an influenza pandemic with inexpensive generic agents: can it be done?

Avian influenza A H5N1 presents a serious and possibly imminent pandemic threat. In such an event, adequate supplies of affordable vaccines and antiviral agents will be unavailable to most people in the world. In view of the overwhelming need for effective alternatives, generic agents that target the host immune response or the pandemic virus should be considered. Many scientists doubt the effectiveness of these agents. Nonetheless, several studies suggest that statins improve outcomes in patients with bacteraemia and pneumonia and might be similarly effective against influenza. An experimental study has shown that the fibrate gemfibrozil, a peroxisome proliferator-activated receptor (PPAR) α agonist, reduces mortality in H2N2 influenza virus-infected mice. There is substantial molecular cross-talk between statins and PPAR agonists, and their clinical effects are additive in patients with cardiovascular diseases. Chloroquine increases endosomal pH, impairing influenza virus release into the cytosol. Statins, fibrates, and chloroquine are produced as generic medications in developing countries. They are inexpensive, could be stockpiled, and would be available on the first pandemic day. With a lack of realistic alternatives for confronting the next pandemic, research is urgently needed to determine whether these and other generic agents could mitigate the effects of what might otherwise become an unprecedented global public-health crisis.

Safety considerations with fibrate therapy

Fibrates are an important class of drugs for the management of dyslipidemia. This class of drugs is generally well tolerated but is infrequently associated with several safety issues. Fibrates, most likely by an effect mediated by peroxisome proliferator-activated receptor-alpha, may reversibly increase creatinine and homocysteine but are not associated with an increased risk for renal failure in clinical trials. Fibrates are associated with a slightly increased risk (<1.0%) for myopathy, cholelithiasis, and venous thrombosis. In clinical trials, patients without elevated triglycerides and/or low high-density lipoprotein cholesterol (HDL) levels, fibrates are associated with an increase in noncardiovascular mortality. In combination with statins, gemfibrozil generally should be avoided. The preferred option is fenofibrate, which is not associated with an inhibition of statin metabolism. Clinicians are advised to measure serum creatinine before fibrate use and adjust the dose accordingly for renal impairment. Routine monitoring of creatinine is not required, but if a patient has a clinically important increase in creatinine, and other potential causes of creatinine increase have been excluded, consideration should be given to discontinuing fibrate therapy or reducing the dose.