Efficacy and safety of proprotein convertase subtilisin-kexin type 9 (PCSK9) inhibitors, alirocumab and evolocumab, a post-commercialization study

PCSK9 Inhibitors and Infection-Related Adverse Events: A Pharmacovigilance Study Using the World Health Organization VigiBase

AIMS

Protein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) are novel lipid-lowering agents used in patients with cardiovascular disease. Despite reassuring safety data from pivotal trials, increasing evidence from real-world studies suggests that PCSK9i increase the risk of bacterial and viral infections. Therefore, this study aimed to identify signals of infection-related adverse events (AEs) associated with PCSK9i.

METHODS

We performed an observational pharmacovigilance study using the World Health Organization's VigiBase, recorded up to December 2022. We included individual case safety reports (ICSRs) of PCSK9 inhibitors, alirocumab and evolocumab, and compared them with those of other drugs. Infection-related ICSRs were retrieved from the Medical Dictionary for Regulatory Activities System Organ Class 'infections and infestations.'

RESULTS

Among 114,293 reports (258,099 drug-AE pairs) related to PCSK9 inhibitors, 54% included female patients, 41% included patients aged ≥65 years, and 82% included patients who received evolocumab. Additionally, beyond AEs recognized by regulatory authorities, organ infections such as influenza (reporting odds ratio [ROR] 2.89, 95% confidence interval [CI] 2.74-3.05), gastric infections (ROR 2.47, 95% CI 1.63-3.75), and kidney infections (ROR 1.36, 95% CI 1.06-1.73) were observed. Sensitivity analysis indicated a heightened risk of infection-related AEs associated with PCSK9i regardless of the specific drug type.

CONCLUSIONS

In addition to the labelled respiratory infections, six infection-related symptoms in the gastrointestinal, urinary, and renal organs were identified. Our findings support the need for systematic surveillance of infections among PCSK9i users.

PCSK9 inhibitors revisited: Effectiveness and safety of PCSK9 inhibitors in a real-life Spanish cohort

INTRODUCTION

Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) have emerged as a therapeutic option for patients with hypercholesterolemia who do not attain low-density lipoprotein cholesterol (LDL-C) goals and/or are intolerant to other lipid-lowering drugs. Our aim was to analyze the effectiveness and safety of PCSK9i in routine clinical practice and factors related to poor outcomes.

MATERIALS AND METHODS

We conducted an ambispective study in 115 patients who recieved alirocumab or evolocumab, in a tertiary level hospital. From February 2017 to April 2020, patients were recruited and followed up for a median of 20.4 months. The main outcomes were relative reduction in LDL-C, percentage of patients achieving the therapeutic goals established by 2016 ESC/EAS guidelines, incidence of major cardiovascular events (MACEs) and drug-related adverse events (ADRs).

RESULTS

The median LDL-C achieved was 57.0 mg/dL (relative reduction of 59.9% from baseline, p< 0.001). After adjusting for confounders, smaller LDL-C reductions were related to female sex, absence of concomitant lipid-lowering therapy and treatment with alirocumab. Overall, 84.6% of the patients achieved the therapeutic goals. During follow-up, 7 MACEs were detected. ADRs, generally considered mild, affected 38.1% of the participants (mainly mialgias and arthralgias) and triggered discontinuations in 8.7% of cases.

CONCLUSIONS

PCSK9i are effective and safe, although certain factors may influence their effectiveness. Interestingly, our results suggest that alirocumab and evolocumab may not be therapeutic equivalents, as initially suggested.

Peptidic vaccines: The new cure for heart diseases?

Cardiovascular disease continues to be the most common cause of death worldwide. The global burden is so high that numerous organizations are providing counseling recommendations and annual revisions of current pharmacological and non-pharmacological treatments as well as risk prediction for disease prevention and further progression. Although primary preventive interventions targeting risk factors such as obesity, hypertension, smoking, and sedentarism have led to a global decline in hospitalization rates, the aging population has overwhelmed these efforts on a global scale. This review focuses on peptidic vaccines, with the known and not well-known autoantigens in atheroma formation or acquired cardiac diseases, as novel potential immunotherapy approaches to counteract harmful heart disease continuance. We summarize how cancer immunomodulatory strategies started novel approaches to modulate the innate and adaptive immune responses, and how they can be targeted for therapeutic purposes in the cardiovascular system. Brief descriptions focused on the processes that start as either immunologic or non-immunologic, and the ultimate loss of cardiac muscle cell contractility as the outcome, are discussed. We conclude debating how novel strategies with nanoparticles and nanovaccines open a promising therapeutic option to reduce or prevent cardiovascular diseases.

PCSK9 Inhibitors: Clinical Relevance, Molecular Mechanisms, and Safety in Clinical Practice

Coronary artery disease (CAD) is one of the leading causes of mortality. High circulating levels of low-density lipoprotein (LDL) in the blood are associated with cardiovascular mortality, whether through an etiological role or through its association with the progression of CAD per se. Randomized clinical trials have shown that, when LDL levels are reduced, cardiovascular risk is also reduced, which reinforces this association. The first major trial involving a hypolipidemic agent of the statin family, the Scandinavian Simvastatin Survival Study (4S), was published in 1994 and found a significant reduction in mortality in patients at high cardiovascular risk. However, even in subsequent studies with different statins, a residual risk persisted, and this seems not to have changed over time; it is speculated that this risk may be due to statin intolerance. In this scenario, the potential exists for novel hypolipidemic agents to drive a true revolution in the therapy of dyslipidemia. The recent discovery of PCSK9 inhibitors (PCSK9i), a class of hypolipidemic monoclonal antibodies, is extremely promising. PCSK9 inhibition is capable of promoting a mean LDL reduction of up to 60%, with potential for very significant clinical repercussions, as every 38 mg/dL reduction in LDL appears to be associated with a 22% reduction in cardiovascular risk. This review addresses a brief history of PCSK9i, major trials of these drugs, cardiovascular outcomes, and aspects related to their efficacy and safety. Finally, the molecular mechanisms and possible pleiotropic effects of PCSK9i are also discussed.

Adverse Events Associated With PCSK9 Inhibitors: A Real-World Experience

In randomized clinical trials (RCTs) proprotein convertase subtilisin/kexin 9 (PCSK9) inhibitors showed a favorable safety profile, however, “real‐world” data on adverse events (AEs) is scarce. Three datasets, a hospital registry (n = 164), and two Pharmacovigilance databases, Lareb (n = 149) and VigiLyze (n = 15,554), reporting AEs attributed to PCSK9 inhibitors (alirocumab or evolocumab) prescribed in clinical practice were analyzed. In the hospital registry, 41.5% of the patients reported any AE, most often injection‐site reactions (33.8%) and influenza‐like illness (27.9%). Twelve patients (7%) discontinued PCSK9 inhibitor treatment. Most common AE reported in the Lareb and VigiLyze database was myalgia (12.8% and 8.3%, respectively). No clinically relevant differences in gender or between drugs were observed. No specific subgroup of patients could be identified at risk of developing AEs. During follow‐up, AEs resolved in most patients (71.1%). In a real‐world setting, PCSK9 inhibitors are well tolerated with an overall safety profile comparable to RCTs.