Unmet Patient Need in Statin Intolerance: the Clinical Characteristics and Management

Di’ao Xinxuekang Capsule Improves the Anti-Atherosclerotic Effect of Atorvastatin by Downregulating the SREBP2/PCSK9 Signalling Pathway

Statins are the first choice for lowering low-density lipoprotein cholesterol (LDL-C) and preventing atherosclerotic cardiovascular disease (ASCVD). However, statins can also upregulate proprotein convertase subtilisin/kexin type 9 (PCSK9), which in turn might limits the cholesterol-lowering effect of statins through the degradation of LDL receptors (LDLR). Di’ao Xinxuekang (DXXK) capsule, as a well-known traditional Chinese herbal medicine for the prevention and treatment of coronary heart disease, can alleviate lipid disorders and ameliorate atherosclerosis in atherosclerosis model mice and downregulate the expression of PCSK9. In this study, we further explored whether DXXK has a synergistic effect with atorvastatin (ATO) and its underlying molecular mechanism. The results showed that both ATO monotherapy (1.3 mg/kg) and ATO combined with DXXK therapy significantly lowered serum lipid levels and reduced the formation of atherosclerotic plaques and the liver lipid accumulation. Moreover, compared with ATO monotherapy, the addition of DXXK (160 mg/kg) to the combination therapy further lowered LDL-C by 15.55% and further reduced the atherosclerotic plaque area by 25.98%. In addition, the expression of SREBP2, PCSK9 and IDOL showed a significant increase in the model group, and the expression of LDLR was significantly reduced; however, there were no significant differences between the ATO (1.3 mg/kg) and the model groups. When ATO was combined with DXXK, the expression of LDLR was significantly increased and was higher than that of the model group and the expression of SREBP2 and PCSK9 in the liver was also significantly inhibited. Moreover, it can be seen that the expression of SREBP2 and PCSK9 in the combination treatment group was significantly lower than that in the ATO monotherapy group (1.3 mg/kg). Besides, the expression of IDOL mRNA in each treatment group was not significantly different from that of the model group. Our study suggests that DXXK might have a synergistic effect on the LDL-C lowering and antiatherosclerosis effects of ATO through the SREBP2/PCSK9 pathway. This indicates that a combination of DXXK and ATO may be a new treatment for atherosclerosis.

Therapeutic Effects of Lipid Lowering Medications on Myocardial Blood Flow, Inflammation, and Sympathetic Nerve Activity Using Nuclear Techniques

PURPOSE OF REVIEW

Statins are routinely applied in patients with coronary artery disease, as they allow significantly to reduce blood cholesterol levels. Although those drugs are endorsed by current guidelines and prescribed routinely, a substantial portion of patients are still statin-intolerant and image-piloted strategies may then be helpful to identify patients that need further intensified treatment, e.g., to initiate treatment with proprotein convertase subtilisin / kexin type 9 inhibitors (PCSK9i). In addition, it has also been advocated that statins exhibit nonlipid, cardio-protective effects including improved cardiac nerve integrity, blood flow, and anti-inflammatory effects in congestive heart failure (HF) patients.

RECENT FINDINGS

In subjects after myocardial infarction treated with statins, ^123II-metaiodobenzylguanidine (MIBG) scintigraphy has already revealed enhanced cardiac nerve function relative to patients without statins. In addition, all of those aforementioned statin-targeted pathways in HF can be visualized and monitored using dedicated cardiac radiotracers, e.g., ¹²³I-MIBG or ¹⁸F-AF78 (for cardiac nerve function), ¹⁸F-flurpiridaz (to determine coronary flow) or ⁶⁸Ga-PentixaFor (to detect inflammation). Statins exhibit various cardio-beneficial effects, including improvement of cardiac nerve function, blood flow, and reduction of inflammation, which can all be imaged using dedicated nuclear cardiac radiotracers. This may allow for in vivo monitoring of statin-induced cardioprotection beyond lipid profiling in HF patients.

Statin intolerance: an updated, narrative review mainly focusing on muscle adverse effects

INTRODUCTION

Statins have been established as the standard of care for dyslipidemia and preventing cardiovascular diseases while posing few safety concerns. However, misconceptions about statin intolerance lead to their underuse, indicating a need to improve the understanding of the safety of this treatment.

AREAS COVERED

We searched PubMed and reviewed literatures related to statin intolerance published between February 2015 and February 2020. Important large-scale or landmark studies published before 2015 were also cited as key evidence.

EXPERT OPINION

Optimal lowering of low-density lipoprotein cholesterol with statins substantially reduces the risk of cardiovascular events. Muscle adverse events (AEs) were the most frequently reported AEs by statin users in clinical practice, but they usually occurred at a similar rate with statins and placebo in randomized controlled trials and had a spurious causal relationship with statin treatment. We proposed a rigorous definition for identifying true statin intolerance and present the criteria for defining different forms of muscle AEs and an algorithm for their management. True statin intolerance is uncommon, and every effort should be made to exclude false statin intolerance and ensure optimal use of statins. For the management of statin intolerance, statin-based approaches should be prioritized over non-statin approaches.

Efficacy and Safety of Bempedoic Acid in Patients With Hypercholesterolemia and Statin Intolerance

Background

Inability to tolerate statins because of muscle symptoms contributes to uncontrolled cholesterol levels and insufficient cardiovascular risk reduction. Bempedoic acid, a prodrug that is activated by a hepatic enzyme not present in skeletal muscle, inhibits ATP‐citrate lyase, an enzyme upstream of β‐hydroxy β‐methylglutaryl‐coenzyme A reductase in the cholesterol biosynthesis pathway.

Methods and Results

The phase 3, double‐blind, placebo‐controlled CLEAR (Cholesterol Lowering via Bempedoic acid, an ACL‐Inhibiting Regimen) Serenity study randomized 345 patients with hypercholesterolemia and a history of intolerance to at least 2 statins (1 at the lowest available dose) 2:1 to bempedoic acid 180 mg or placebo once daily for 24 weeks. The primary end point was mean percent change from baseline to week 12 in low‐density lipoprotein cholesterol. The mean age was 65.2 years, mean baseline low‐density lipoprotein cholesterol was 157.6 mg/dL, and 93% of patients reported a history of statin‐associated muscle symptoms. Bempedoic acid treatment significantly reduced low‐density lipoprotein cholesterol from baseline to week 12 (placebo‐corrected difference, −21.4% [95% CI, −25.1% to −17.7%]; P<0.001). Significant reductions with bempedoic acid versus placebo were also observed in non–high‐density lipoprotein cholesterol (−17.9%), total cholesterol (−14.8%), apolipoprotein B (−15.0%), and high‐sensitivity C‐reactive protein (−24.3%; P<0.001 for all comparisons). Bempedoic acid was safe and well tolerated. The most common muscle‐related adverse event, myalgia, occurred in 4.7% and 7.2% of patients who received bempedoic acid or placebo, respectively.

Conclusions

Bempedoic acid offers a safe and effective oral therapeutic option for lipid lowering in patients who cannot tolerate statins.

Clinical Trial Registration

URL: https://www.clinicaltrials.gov. Unique identifier: NCT02988115.

See Editorial by Jia and Virani

LDL-cholesterol: The lower the better

The reduction of low density lipoprotein-cholesterol (LDL-chol) has been associated with a decrease in cardiovascular morbidity and mortality. It has been demonstrated that there is no value of LDL-chol below which there ceases to be a preventive benefit with its reduction, and neither has it been observed that there is a higher incidence of secondary effects associated with lower concentrations of LDL-chol. Although there is a wide range of lipid-lowering drugs available, a high percentage of patients do not achieve the desired LDL-chol levels. The high-potency statins reduce the LDL-chol by 15-30%, and can double the percentage of patients that reach their desired level. This combination has shown to be safe and effective in the primary and secondary prevention of cardiovascular disease. Another option is the combination of statins with exchange resins, although this requires a more complex management. The inhibition of PCSK9 protein with monoclonal antibodies reduces the LDL-chol by more than 60%, and is effective in the prevention of cardiovascular disease. However, due to its cost, its use is restricted to patients with ischaemia or familial hypercholesterolaemia that do not achieve the desired levels with conventional drugs. The evidence base as regards the benefit and safety of achieving the desired levels of LDL-chol is very wide and is still increasing. In the next few years, it may be necessary to adjust the intensity of the hypercholesterolaemia treatment to the level of vascular risk of the patients, and to the level of reduction necessary to achieve the therapeutic targets. This will result in a more effective cardiovascular prevention and in a better quality of life, particularly in the large group of patients at higher vascular risk.

Persistent Safety and Efficacy of Evolocumab in Patients with Statin Intolerance: a Subset Analysis of the OSLER Open-Label Extension Studies

PURPOSE

Evolocumab reduced low-density lipoprotein cholesterol (LDL-C) in 12-week trials in statin-intolerant patients (GAUSS-1 and GAUSS-2); however, the persistence of efficacy during longer-term treatment is unknown. This subset analysis of the open-label extension studies (OSLER-1 and OSLER-2) aimed to evaluate the safety and efficacy of evolocumab up to 2 years in statin-intolerant patients.

METHODS

Patients who completed GAUSS-1 and GAUSS-2 were enrolled in the OSLER studies and rerandomized 2:1 to evolocumab (140 mg biweekly or 420 mg monthly) plus standard of care (SOC) or SOC during year 1, and thereafter, evolocumab plus SOC.

RESULTS

A total of 382 statin-intolerant patients who completed the GAUSS-1 and GAUSS-2 parent studies were enrolled and rerandomized into the OSLER studies. After year 1, 246 (98%) patients randomized to evolocumab plus SOC and 124 (95%) on SOC during year 1 remained in the OSLER studies; after year 2, 364 (95%) remained on study. Mean parent study baseline LDL-C concentration was 4.97-5.02 mmol/L (192-194 mg/dL). The median percentage reduction from baseline in LDL-C was 13% for SOC and 57% for evolocumab plus SOC at year 1, and 59% for evolocumab plus SOC at year 2. The patient incidence of muscle-related adverse events during year 1 in the SOC and evolocumab plus SOC groups was 16% and 14%, respectively, and 11% for evolocumab plus SOC at year 2. No patient discontinued the study due to adverse events.

CONCLUSION

Evolocumab plus SOC was persistently safe, tolerable, and efficacious for up to 2 years in statin-intolerant patients.

Statin-Associated Muscle Disease: Advances in Diagnosis and Management

Since the first approval of lovastatin in 1987, hydroxy-methyl-glutaryl CoA (HMG CoA) reductase inhibitors, or statins, have been effective and widely popular cholesterol-lowering agents with substantial benefits for the prevention and treatment of cardiovascular disease. Not all patients can tolerate these drugs, however, and statin intolerance is most frequently associated with a range of side effects directed toward skeletal muscle, termed statin-associated muscle symptoms or SAMS. SAMS are particularly difficult to treat because there are no validated biomarkers or tests that can be used to confirm patient self-reports of SAMS, and a number of patients who report SAMS have non-specific muscle pain not attributable to statin therapy. This review summarizes the most recent evidence related to diagnosis and management of SAMS. First, the range of skeletal muscle side effects associated with statin therapy is described. Second, data regarding the incidence and prevalence of SAMS, the most frequently experienced muscle side effect, are presented. Third, the most promising new techniques to confirm diagnosis of SAMS are explored. Finally, the most effective strategies for the clinical management of SAMS are summarized. Better diagnostic and treatment strategies for SAMS will increase the number of patients using these life-saving statins, thereby increasing statin adherence and reducing the costs of avoidable cardiovascular events.