Efficacy and safety of alirocumab among individuals with diabetes mellitus and atherosclerotic cardiovascular disease in the ODYSSEY phase 3 trials

Advanced progress of the relationship between PCSK9 monoclonal antibodies and hyperglycemic adverse events

Purpose of Review

Long-term use of statins had been confirmed to cause an increase in hyperglycemic adverse events (HAEs), whose mechanism has been well understood. Proprotein convertase subtilisin/kexin type 9 (PCSK9) monoclonal antibodies (PCSK9-mAbs), a kind of new lipid-lowering drug, can effectively reduce plasma low-density lipoprotein cholesterol levels in patients with CHD and have been widely used. However, animal experiments, Mendelian randomization studies, clinical researches and Meta-analyses which focused on the relationship between PCSK9-mAbs and HAEs had reached different conclusions, which has attracted great attention from clinicians.

Recent Findings

The newest FOURIER-OLE randomized controlled trial followed PCSK9-mAbs users for over 8 years, whose results suggested that long-term use of PCSK9-mAbs did not increase the incidence of HAEs. Newest Meta-analyses also indicated that there was no relationship between PCSK9-mAbs and NOD. Meanwhile, genetic polymorphisms and variants related to PCSK9 might have effects on HAEs.

Conclusion

According to the results of current studies, there is no significant relationship between PCSK9-mAbs and HAEs. However, longer-term follow-up studies are still needed to confirm it. Although PCSK9 genetic polymorphisms and variants may affect the possible occurrence of HAEs, there is no need to perform relevant genetic testing before applying PCSK9-mAbs.

Insight into the role of PCSK9 in glucose metabolism

Diabetes mellitus (DM) is strongly associated with an increased risk of atherosclerotic cardiovascular disease (ASCVD). Proprotein convertase subtilisin/kexin type 9 (PCSK9) was recently identified as an important regulator of circulating low-density lipoprotein-cholesterol (LDL-C) levels via degradation of the LDL receptor, proving to be a valid target to improve lipoprotein profiles and cardiovascular outcomes in patients with ASCVD. Beyond LDL receptor processing and cholesterol homeostasis, the PCSK9 protein has recently been verified to be associated with glucose metabolism. Importantly, clinical trials suggest that treatment with PCSK9 inhibitors for patients with DM is more effective. Hence, in this review, we summarize the current findings derived from experimental, preclinical, and clinical studies regarding the association between PCSK9 and glucose metabolism, including the relationship of PCSK9 genetic mutations to glucose metabolism and diabetes, the link between plasma PCSK9 concentrations and glucose metabolic parameters, the effects of glucose-lowering drugs on plasma PCSK9 levels and the impacts of PCSK9 inhibitors on cardiovascular outcomes of patients with DM. Clinically, exploring this field may improve our understanding regarding the roles of PCSK9 in glucose metabolism and may offer an in-depth interpretation of how PCSK9 inhibitors exert effects on the treatment of patients with DM.

Diabetes and Familial Hypercholesterolemia: Interplay between Lipid and Glucose Metabolism

Familial hypercholesterolemia (FH) is a genetic disease characterized by high low-density lipoprotein (LDL) cholesterol (LDL-c) concentrations that increase cardiovascular risk and cause premature death. The most frequent cause of the disease is a mutation in the LDL receptor (LDLR) gene. Diabetes is also associated with an increased risk of cardiovascular disease and mortality. People with FH seem to be protected from developing diabetes, whereas cholesterol-lowering treatments such as statins are associated with an increased risk of the disease. One of the hypotheses to explain this is based on the toxicity of LDL particles on insulin-secreting pancreatic β-cells, and their uptake by the latter, mediated by the LDLR. A healthy lifestyle and a relatively low body mass index in people with FH have also been proposed as explanations. Its association with superimposed diabetes modifies the phenotype of FH, both regarding the lipid profile and cardiovascular risk. However, findings regarding the association and interplay between these two diseases are conflicting. The present review summarizes the existing evidence and discusses knowledge gaps on the matter.

Proteinuria converts hepatic heparan sulfate to an effective proprotein convertase subtilisin kexin type 9 enzyme binding partner

Hepatic uptake of triglyceride-rich remnant lipoproteins is mediated by the low-density lipoprotein receptor, a low-density lipoprotein receptor related protein and the heparan sulfate proteoglycan, syndecan-1. Heparan sulfate proteoglycan also mediates low-density lipoprotein receptor degradation by a regulator of cholesterol homeostasis, proprotein convertase subtilisin kexin type 9 (PCSK9), thereby hampering triglyceride-rich remnant lipoproteins uptake. In this study, we investigated the effects of proteinuria on PCSK9, hepatic heparan sulfate proteoglycan and plasma triglyceride-rich remnant lipoproteins. Adriamycin-injected rats developed proteinuria, elevated triglycerides and total cholesterol (all significantly increased). Proteinuria associated with triglycerides and total cholesterol and serum PCSK9 (all significant associations) without loss of the low-density lipoprotein receptor as evidenced by immunofluorescence staining and western blotting. In proteinuric rats, PCSK9 accumulated in sinusoids, whereas in control rats PCSK9 was localized in the cytoplasm of hepatocytes. Molecular profiling revealed that the heparan sulfate side chains of heparan sulfate proteoglycan to be hypersulfated in proteinuric rats. Competition assays revealed sulfation to be a major determinant for PCSK9 binding. PCSK9 partly colocalized with hypersulfated heparan sulfate in proteinuric rats, but not in control rats. Hence, proteinuria induces hypersulfated hepatic heparan sulfate proteoglycans, increasing their affinity to PCSK9. This might impair hepatic triglyceride-rich remnant lipoproteins uptake, causing proteinuria-associated dyslipidemia. Thus, our study reveals PCSK9/heparan sulfate may be a novel target to control dyslipidemia.

Cardiovascular Outcomes and Proprotein Convertase Subtilisin/Kexin Type 9 Inhibitors: Current Data and Future Prospects

Cardiovascular (CV) disease remains the leading cause of morbidity and mortality worldwide and poses an ongoing challenge with the aging population. Elevated low-density lipoprotein cholesterol (LDL-C) is an established risk factor for atherosclerotic cardiovascular disease (ASCVD), and the expert consensus is the use of statin therapy (if tolerated) as first line for LDL-C reduction. However, patients with ASCVD may experience recurrent ischemic events despite receiving maximally tolerated statin therapy, including those whose on-treatment LDL-C remains ≥70 mg/dL, patients with familial hypercholesterolemia, high-risk subgroups with comorbidities such as diabetes mellitus, and those who have an intolerance to statin therapy. Optimal therapeutic strategies for this unmet need should deploy aggressive lipid lowering to minimize the contribution of dyslipidemia to their CV risk, particularly for very high-risk populations with additional risk factors beyond hypercholesterolemia and established ASCVD. To understand the current clinical climate and guidelines regarding ASCVD, we primarily searched PubMed for articles published in English regarding lipid-lowering therapies and CV risk reduction, including emerging therapies, and CV outcomes trials with proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors. This review discusses the findings of recent clinical trial evidence for CV risk reduction with cholesterol-lowering therapies, with a focus on CV outcomes trials with PCSK9 inhibitors, and considers the impact of the study results for secondary prevention and future strategies in patients with hypercholesterolemia and CV risk despite maximally tolerated statin therapy.

Diabetes and Vascular Disease: Is It All About Glycemia?

BACKGROUND

Diabetes is increasing over time, mainly driven by obesity, aging, and urbanization. Classical macro- and microvascular complications represent the final result of a complex interplay involving atherosclerosis at all stages.

METHODS

In this review, we aim at focusing on current updates in the pathophysiology of vascular disease in diabetes and discussing how new therapies might influence the management of these patients at high cardiovascular risk. Diabetes shows accelerated atherosclerosis with a larger inflammatory cell infiltrate, thus favoring the development of heart failure. 'Diabetic cardiomyopathy' perfectly describes a specific ischemia- and hypertension- independent entity due to diabetes-related metabolic alterations on myocardial function. Moreover, platelets from subjects with diabetes display a typical hyperreactivity explaining the stronger adhesion, activation, and aggregation. Additionally, diabetes provokes an exaggerated stimulation of the endothelium, with an increased release of reactive oxygen species and a reduced release of nitric oxide, both key elements of the endothelial dysfunction. Also, the coagulation cascade and leukocytes activate contributing to this pro-thrombotic environment. Neutrophils have been recently recognized to play a pivotal role by releasing neutrophil extracellular traps. Finally, microparticles from platelets, neutrophils or monocytes are detrimental effectors on the vessel wall and are involved both in vascular dysfunction and in thrombotic complications.

CONCLUSION

In light of these findings, the therapeutic management of diabetes needs to be mostly focused on limiting the progression of complications by targeting precise pathophysiological mechanisms rather than the mere glycemic control, which failed to markedly reduce the risk for macrovascular complications and mortality.

Randomised study of evolocumab in patients with type 2 diabetes and dyslipidaemia on background statin: Primary results of the BERSON clinical trial

AIM

To evaluate the lipid-lowering efficacy and safety of evolocumab combined with background atorvastatin in patients with type 2 diabetes mellitus (T2DM) and hyperlipidaemia or mixed dyslipidaemia.

MATERIALS AND METHODS

BERSON was a double-blind, 12-week, phase 3 study (NCT02662569) conducted in 10 countries. Patients ≥18 to ≤80 years with type T2DM received atorvastatin 20 mg/d and were randomised 2:2:1:1 to evolocumab 140 mg every 2 weeks (Q2W) or 420 mg monthly (QM) or placebo Q2W or QM. Co-primary endpoints were the percentage change in low-density lipoprotein cholesterol (LDL-C) from baseline to week 12 and from baseline to the mean of weeks 10 and 12. Additional endpoints included atherogenic lipids, glycaemic measures, and adverse events (AEs).

RESULTS

Overall, 981 patients were randomised and received ≥1 dose of study drug. Evolocumab significantly reduced LDL-C versus placebo at week 12 (Q2W, -71.8%; QM, -74.9%) and at the mean of weeks 10 and 12 (Q2W, -70.3%; QM, -70.0%; adjusted P < 0.0001 for all) when administered with atorvastatin. Non-high-density lipoprotein cholesterol, apolipoprotein B100, total cholesterol, lipoprotein (a), triglycerides, high-density lipoprotein cholesterol, and very low-density lipoprotein cholesterol improved significantly with evolocumab versus placebo. The overall incidence of AEs was similar between evolocumab and placebo-treated patients, and there were no clinically meaningful differences in changes over time in glycaemic variables (fasting serum glucose and HbA1c) between the two groups.

CONCLUSIONS

In patients with T2DM and hyperlipidaemia or mixed dyslipidaemia on statin, evolocumab significantly reduced LDL-C and other atherogenic lipids, was well tolerated, and had no notable impact on glycaemic measures.

Randomized study of evolocumab in patients with type 2 diabetes and dyslipidaemia on background statin: Pre-specified analysis of the Chinese population from the BERSON clinical trial

AIM

The aim of this study was to evaluate the efficacy and safety of evolocumab with background atorvastatin in Chinese patients with type 2 diabetes mellitus (T2DM) and hyperlipidaemia or mixed dyslipidaemia.

MATERIALS AND METHODS

This is a pre-specified analysis of patients in the BERSON study (ClinicalTrials.gov, NCT02662569) in China. Patients initiated background atorvastatin 20 mg/d, after which they were randomized 2:2:1:1 to evolocumab 140 mg every 2 weeks (Q2W) or 420 mg monthly (QM) or to placebo Q2W or QM. Co-primary endpoints were percentage change in LDL cholesterol (LDL-C) from baseline to week 12 and from baseline to the mean of weeks 10 and 12. Additional endpoints included atherogenic lipids, glycaemic measures and adverse events (AEs).

RESULTS

Among 453 patients randomized in China, 451 received at least one dose of study drug (evolocumab or placebo). Evolocumab significantly reduced LDL-C compared with placebo at week 12 (Q2W, -85.0%; QM, -74.8%) and at the mean of weeks 10 and 12 (Q2W, -80.4%; QM, -81.0%) (adjusted P < 0.0001 for all) when administered with background atorvastatin. Non-HDL-C, ApoB100, total cholesterol, Lp(a), triglycerides, HDL-C and VLDL-C significantly improved with evolocumab vs placebo. No new safety findings were observed with evolocumab. The incidence of diabetes AEs was higher with evolocumab compared with placebo. There were no differences over time between evolocumab and placebo in measures of glycaemic control.

CONCLUSIONS

In patients in China with T2DM and hyperlipidaemia or mixed dyslipidaemia receiving background atorvastatin, evolocumab significantly reduced LDL-C and other atherogenic lipids, was well tolerated, and had no notable impact on glycaemic measures.

Efficacy and safety of proprotein convertase subtilisin/kexin 9 inhibitors in people with diabetes and dyslipidaemia

Diabetic dyslipidaemia, characterized by quantitative, qualitative and kinetic changes in all major circulating lipids, contributes to the increased cardiovascular risk in patients with type 2 diabetes mellitus (T2DM). A promising therapeutic avenue is the inhibition of the proprotein convertase subtilisin kexin 9 (PCSK9) with human monoclonal antibodies (mAbs) that potently reduce plasma low-density lipoprotein cholesterol (LDL-C) levels on top of statin treatment. The aim of this review is to evaluate the efficacy of PCSK9 inhibitors to lower the residual cardiovascular risk of T2DM patients and to discuss the safety of PCSK9 inhibition in these patients. PCSK9 inhibitors potently lower plasma LDL-C levels in T2DM patients and reduce risk for the development of cardiovascular disease. Anti-PCSK9 mAbs are generally not more or less effective in T2DM patients compared to a general high-risk population. Nevertheless, due to their higher cardiovascular risk, the absolute risk reduction of major cardiovascular events is more significant in T2DM patients. This suggests that treatment of T2DM patients with anti-PCSK9 mAbs could be attractive from a cost-effectiveness perspective. Treatment with anti-PCSK9 mAbs did not result in significant treatment-emergent adverse effects. While genetic studies suggest a potential link between PCSK9 inhibition and glucose homeostasis, anti-PCSK9 mAbs did not worsen glycaemic control in T2DM patients, but their safety should be verified after a longer-term follow-up.

Beyond Statins: Who and When to Prescribe?

PURPOSE OF REVIEW

Statins are the most evidence-based therapy to target LDL-C to reduce atherosclerotic events. Yet, many people are unable to achieve adequate reduction in this key atherogenic factor. Moreover, residual risk of cardiovascular events may persist even after "optimal" LDL-C due to elevations in triglyceride-rich lipoproteins. Therefore, additional therapies beyond statins are needed, particularly in patients with diabetes.

RECENT FINDINGS

Clinical trials with ezetimibe and PCSK9 inhibitors have reported further reductions in cardiovascular events, beyond statins. The latter are particularly effective in lowering LDL-cholesterol and in reducing event rates. However, they are not effective in lowering triglycerides. Currently available fibrates and niacin have not proven effective in combination with statins in clinical trials, while the top line results of the REDUCE-IT trial with EPA, a pure omega-3 fatty acid, reporting 25% relative risk reduction in primary endpoints are of great interest. Recently approved agents have the promise to improve cardiovascular outcomes beyond statins. Many novel drugs in development have the potential to further improve prognosis.

Efficacy and safety of alirocumab among individuals with diabetes mellitus and atherosclerotic cardiovascular disease in the ODYSSEY phase 3 trials

AIMS

Individuals with both diabetes mellitus (DM) and atherosclerotic cardiovascular disease (ASCVD) are at very high risk of cardiovascular events. This post-hoc analysis evaluated efficacy and safety of the PCSK9 inhibitor alirocumab among 984 individuals with DM and ASCVD pooled from 9 ODYSSEY Phase 3 trials.

MATERIALS AND METHODS

Changes in low-density lipoprotein cholesterol (LDL-C) and other lipids from baseline to Week 24 were analysed (intention-to-treat) in four pools by alirocumab dosage (150 mg every 2 weeks [150] or 75 mg with possible increase to 150 mg every 2 weeks [75/150]), control (placebo/ezetimibe) and background statin usage (yes/no).

RESULTS

At Week 24, LDL-C changes from baseline in pools with background statins were -61.5% with alirocumab 150 (vs -1.0% with placebo), -46.4% with alirocumab 75/150 (vs +6.3% with placebo) and -48.7% with alirocumab 75/150 (vs -20.6% with ezetimibe), and -54.9% with alirocumab 75/150 (vs +4.0% with ezetimibe) without background statins. A greater proportion of alirocumab recipients achieved LDL-C < 70 and < 55 mg/dL at Week 24 vs controls. Alirocumab also resulted in significant reductions in non-high-density lipoprotein cholesterol, apolipoprotein B and lipoprotein(a) vs controls. Alirocumab did not appear to affect glycaemia over 78-104 weeks. Overall safety was similar between treatment groups, with a higher injection-site reaction frequency (mostly mild) with alirocumab.

CONCLUSION

Alirocumab significantly reduced LDL-C and other atherogenic lipid parameters, and was generally well tolerated in individuals with DM and ASCVD.