Phase 2 clinical trials with K-877 (pemafibrate): A promising selective PPAR-α modulator for treatment of combined dyslipidemia

Drug Discovery for Coronary Artery Disease

Cardiovascular disease is the number one cause of human morbidity and mortality worldwide. Although cholesterol-lowering drugs, including statins and recently approved PCSK9 inhibitors, together with antithrombotic drugs have been historically successful in reducing the occurrence of coronary artery disease (CAD), the high incidence of CAD remains imposing the largest disease burden on our healthcare systems. We reviewed cardiovascular drugs recently approved or under clinical development, with a particular focus on their pharmacology and limitations. New agents targeting cholesterol/triglyceride lowering bear promise of further cardiovascular risk reduction. Some new antidiabetic agents show cardiovascular benefit in patients with diabetes. Improved antithrombotic agents with diminished bleeding risk are in clinical development. The recent clinical success of the IL-1β antibody in reducing atherothrombosis opens a new era of therapeutic discovery that targets inflammation. Chinese traditional medicine and cardiac regeneration are also discussed. Human genetics studies of CAD and further delineation of key determinants/pathways underlying the residual risk of CAD under current standard therapy will continue to fuel the pipeline of cardiovascular drug discovery.

Molecular Actions of PPARα in Lipid Metabolism and Inflammation

Peroxisome proliferator-activated receptor α (PPARα) is a nuclear receptor of clinical interest as a drug target in various metabolic disorders. PPARα also exhibits marked anti-inflammatory capacities. The first-generation PPARα agonists, the fibrates, have however been hampered by drug-drug interaction issues, statin drop-in, and ill-designed cardiovascular intervention trials. Notwithstanding, understanding the molecular mechanisms by which PPARα works will enable control of its activities as a drug target for metabolic diseases with an underlying inflammatory component. Given its role in reshaping the immune system, the full potential of this nuclear receptor subtype as a versatile drug target with high plasticity becomes increasingly clear, and a novel generation of agonists may pave the way for novel fields of applications.

Towards more specific treatment for diabetic dyslipidemia

PURPOSE OF REVIEW

Treatment of diabetic dyslipidemia is necessary because of its impact on cardiovascular disease, which is the leading cause of death in patients with diabetes. In the past, standard treatment of diabetic dyslipidemia focused only on correcting lipids. Although this remains the mainstay of treatment, because new antihyperglycemic treatments reduce cardiovascular events with minimal effect on dyslipidemia, a new approach is both timely and relevant.

RECENT FINDINGS

LDL-lowering remains the focus of treatment for diabetic dyslipidemia, especially in patients with both diabetes and cardiovascular disease (CVD). Higher intensity statin therapy or lower LDL cholesterol goals are recommended in these patients. Combination therapy, especially with ezetimibe, fibrates, bile acid sequestrants, PCSK9 inhibitors and omega 3 fatty acids should be considered along with selected new agents to reduce glycemia.

SUMMARY

As diabetic dyslipidemia plays a key role in CVD, aggressive treatment is indicated. New research targets include apo-CIII and lipoprotein(a) [Lp(a)]. In addition, new antihyperglycemic therapy is changing diabetes care and altering treatment guidelines. The most recent American Diabetes Association Standards of Care has expanded its recommendations for people with CVD and diabetes, suggesting that medications validated to improve cardiac health should be strongly considered.

PPAR Agonists and Metabolic Syndrome: An Established Role?

Therapeutic approaches to metabolic syndrome (MetS) are numerous and may target lipoproteins, blood pressure or anthropometric indices. Peroxisome proliferator-activated receptors (PPARs) are involved in the metabolic regulation of lipid and lipoprotein levels, i.e., triglycerides (TGs), blood glucose, and abdominal adiposity. PPARs may be classified into the α, β/δ and γ subtypes. The PPAR-α agonists, mainly fibrates (including newer molecules such as pemafibrate) and omega-3 fatty acids, are powerful TG-lowering agents. They mainly affect TG catabolism and, particularly with fibrates, raise the levels of high-density lipoprotein cholesterol (HDL-C). PPAR-γ agonists, mainly glitazones, show a smaller activity on TGs but are powerful glucose-lowering agents. Newer PPAR-α/δ agonists, e.g., elafibranor, have been designed to achieve single drugs with TG-lowering and HDL-C-raising effects, in addition to the insulin-sensitizing and antihyperglycemic effects of glitazones. They also hold promise for the treatment of non-alcoholic fatty liver disease (NAFLD) which is closely associated with the MetS. The PPAR system thus offers an important hope in the management of atherogenic dyslipidemias, although concerns regarding potential adverse events such as the rise of plasma creatinine, gallstone formation, drug-drug interactions (i.e., gemfibrozil) and myopathy should also be acknowledged.

[Pharmacological targets for dislipidemies correction. Opportunities and prospects of therapeutic usage]

Literature data on influence of existing and new groups of drug preparations for dyslipidemias correction are systemized, and molecular mechanisms of their effects are reviewed. The results of experimental and clinical investigations aimed at revealing of new pharmacological targets of dyslipidemias correction were analyzed. The approaches for activation of high density lipoproteins functionality are described. The implementation of alternative preparations with new alternative mechanisms of action may be suggested to improve the effectiveness of traditional treatment in the future.

Treatment of Dyslipidemia in Diabetes: Recent Advances and Remaining Questions

PURPOSE OF REVIEW

This article reviews current knowledge concerning diabetic dyslipidemia and cardiovascular disease (CVD). It reviews strategies to reduce diabetes-associated CVD, including reducing low-density lipoprotein levels, lowering triglycerides, and increasing high-density lipoproteins (HDL). Special considerations, such as the multifactorial chylomicronemia syndrome and partial lipodystrophy, and the role of glucose-lowering strategies in the management of diabetic dyslipidemia are discussed.

RECENT FINDINGS

The strongest evidence to date for reducing CVD in diabetes comes from the use of statins. While triglyceride lowering remains inconclusive, an ongoing trial might provide some finality to this question. The role of increasing HDL remains elusive, and HDL cholesterol appears to be an unsatisfactory metric for monitoring therapy. The use of statins offers the best current way to reduce diabetes-associated CVD. However, several novel and promising approaches for the management of diabetic dyslipidemia aimed at reducing CVD are in the pipeline.

Incorporation of PCSK9 inhibitors into prevention of atherosclerotic cardiovascular disease

Primary and secondary prevention of atherosclerotic cardiovascular disease (ASCVD) has become recently more complex than ever, leaving the clinicians perplexed with outdated guidelines and emerging evidence about new LDL-C lowering therapies. 2013 American College of Cardiology (ACC)/American Heart Association (AHA) guidelines have focused on high intensity statin therapy for specific groups of patients, while abandoning long established LDL-C goals, a strategy which no longer seems valid. PCSK9 (proprotein convertase subtilisin/kexin type 9) inhibitors have emerged as the add-on therapy on top of statins and/or ezetimibe for the treatment of hypercholesterolemia and ASCVD prevention. In several clinical trials, PCSK9 inhibitors have demonstrated their safety and robust LDL-C-lowering power. One completed cardiovascular (CV) outcomes trial (FOURIER; Further Cardiovascular Outcomes Research with PCSK9 Inhibitions in Subjects with Elevated Risk) has demonstrated that PCSK9 inhibition reduces rates of CV death as well as non-fatal stroke and MI, while another major CV outcome trial is under way (ODYSSEY-OUTCOMES). Several trials studying CV benefits of novel LDL-C-lowering therapies are also being conducted. Prompt revision of ACC/AHA guidelines is necessary. In the meantime, physicians need to use clinical judgment integrating the most recent evidence into their practice.