Adverse event profiles of PCSK9 inhibitors alirocumab and evolocumab: data mining of the FDA Adverse Event Reporting System

How safe are proprotein convertase subtilisinekexin type 9 inhibitors in diabetes?

PURPOSE OF REVIEW

To examine the safety of proprotein convertase subtilisinekexin type 9 (PCSK9) inhibitors in patients with diabetes, specifically focusing on their impact on glucose metabolism.

RECENT FINDINGS

Patients with diabetes often require intensified lipid-lowering therapy. PCSK9 inhibitors can reduce low-density lipoprotein cholesterol (LDL-C) concentrations by approximately 60%, and significantly reduce cardiovascular risk when added to statin therapy. Some studies have suggested an association between low LDL-C levels and an increased risk of new-onset diabetes, and genetics has almost consistently shown an increased glucose concentration and risk of diabetes. Most clinical trials have not demonstrated a deterioration in glycaemic control in patients with diabetes after the use of PCSK9 inhibitors, and they do not lead to other significant treatment-emergent adverse events.

SUMMARY

Although the majority of patients with diabetes are undergoing background statin therapy, which may mask potential adverse effects of PCSK9 inhibitors on glycaemic control, current data suggest that the benefits outweigh the risks for diabetic patients using PCSK9 inhibitors. Considering the different nature of genetic studies and of clinical trials, close monitoring of glucose parameters is necessary, especially in individuals with prediabetes.

Safety of cardiovascular disease drugs approved between 2014 and 2021 in the US: a pharmacovigilance analysis

BACKGROUND

Recently FDA-approved drugs for cardiovascular disease (CVD) require robust post-marketing surveillance. The objective of this study was to assess their safety using a large pharmacovigilance database.

RESEARCH DESIGN AND METHODS

We analyzed adverse event (AE) reports for 17 drugs approved from 2014 to 2021, utilizing the FDA Adverse Event Reporting System (FAERS). Descriptive and disproportionality analyses were conducted by estimating the reporting odds ratio (ROR) and its 95% confidence interval.

RESULTS

Among the 43,664,773 AE reports 97,702 (0.22%) were related to newly approved CVD drugs. No AEs were reported for finerenone and evinacumab. The results from the disproportionality analyses revealed potential risks of acute kidney injury (ROR = 8.24, 95% CI: 6.05-11.22), cardiac failure (ROR = 4.80, 95% CI: 3.82-6.05), and hypotension (ROR = 3.98, 95% CI: 3.44-4.61) among sacubitril/valsartan users. Additionally, ivabradine was found to be associated with tachycardia (ROR = 11.94, 95% CI: 8.35-17.08), abnormal feeling (ROR = 4.40, 95% CI: 2.70-7.18), and dizziness (ROR = 2.56, 95% CI: 1.68-3.90).

CONCLUSIONS

This study identified specific safety concerns related to recently approved CVD drugs. Further research is required to understand the underlying mechanisms and clinical implications of these findings.

Adverse drug events associated with linezolid administration: a real-world pharmacovigilance study from 2004 to 2023 using the FAERS database

Introduction: Linezolid is an oxazolidinone antibiotic that is active against drug-resistant Gram-positive bacteria and multidrug-resistant Mycobacterium tuberculosis. Real-world studies on the safety of linezolid in large populations are lacking. This study aimed to determine the adverse events associated with linezolid in real-world settings by analyzing data from the US Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS). Methods: We retrospectively extracted reports on adverse drug events (ADEs) from the FAERS database from the first quarter of 2004 to that of 2023. By using disproportionality analysis including reporting odds ratio (ROR), proportional reporting ratio (PRR), Bayesian Confidence Propagation Neural Network (BCPNN), along with the multi-item gamma Poisson shrinker (MGPS), we evaluated whether there was a significant association between linezolid and ADE. The time to onset of ADE was further analyzed in the general population and within each age, weight, reporting population, and weight subgroups. Results: A total of 11,176 reports of linezolid as the "primary suspected" drug and 263 significant adverse events of linezolid were identified, including some common adverse events such as thrombocytopenia (n = 1,139, ROR 21.98), anaemia (n = 704, ROR 7.39), and unexpected signals that were not listed on the drug label such as rhabdomyolysis (n = 90, ROR 4.33), and electrocardiogram QT prolonged (n = 73, ROR 4.07). Linezolid-induced adverse reactions involved 27 System Organ Class (SOC). Gender differences existed in ADE signals related to linezolid. The median onset time of all ADEs was 6 days, and most ADEs (n = 3,778) occurred within the first month of linezolid use but some may continue to occur even after a year of treatment (n = 46). Conclusion: This study reports the time to onset of adverse effects in detail at the levels of SOC and specific preferred term (PT). The results of our study provide valuable insights for optimizing the use of linezolid and reducing potential side effects, expected to facilitate the safe use of linezolid in clinical settings.

Alirocumab-associated unilateral posterior uveitis

A man in his mid-40s who had been recently started on alirocumab (a human monoclonal antibody which inhibits proprotein convertase subtilisin/kexin type 9) due to his strong familial cardiovascular risk and refractory hypercholesterolaemia presented with a few-hour history of acute-onset left-sided blurred vision. The best-corrected visual acuities were 6/6 bilaterally and slit-lamp examination was normal. However, optical coherence tomography revealed serous subretinal fluid in the left macula. Optos ultra-widefield retinal imaging and fundus autofluorescence, along with a set of blood tests, did not reveal any alternative causes. A diagnosis of alirocumab-associated uveitis was diagnosed. Alirocumab was stopped and he was followed up in uveitis clinic. Within 4 months following alirocumab cessation, the subretinal fluid resolved completely. This case report emphasises the importance of early multidisciplinary team involvement, since novel therapeutic agents can have unexpected adverse events.

Identification of benzothiazoles as novel PCSK9 inhibitors

Proprotein convertase subtilisin kexin type 9 (PCSK9) is a clinically validated target on the treatment of cardiovascular disease (CVD). PCSK9 can regulate the hepatocyte surface low density lipoprotein receptor (LDLR) level by binding to LDLR and leading to their degradation in the lysosome. The clinical use of two monoclonal antibodies (alirocumab and evolocumab, approved in 2015) and one small interfering RNA (inclisiran, approved in 2020) which can inhibit PCSK9 function proved that they are very effective in lowering low density lipoprotein cholesterol (LDL-C). However, the high treatment costs and parenteral administration of these drugs prohibited widespread use and reduced their long-term advantage. Comparatively, small molecule drugs have many incomparable advantages of macromolecules, such as lower treatment cost, more drug administration options, superior pharmacokinetic properties, less adverse immunogenic responses and better affordable production. In this paper, we identified a series of benzothiazoles small molecule PCSK9 inhibitors through extensive screening. The structure and activity relationship (SAR) was summarized to facilitate further optimization. Moreover, the primary mechanism of action of the most potent compound was also investigated.

Treatment with Proprotein Convertase Subtilisin/Kexin Type 9 Inhibitors (PCSK9i): Current Evidence for Expanding the Paradigm?

Background: Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) are low-density lipoprotein cholesterol (LDL-C)-lowering drugs that play a critical role in lipoprotein clearance and metabolism. PCSK9i are used in patients with familial hypercholesterolemia and for the secondary prevention of acute cardiovascular events in patients with atherosclerotic cardiovascular disease (CVD). Methods: We focused on the literature from 2015, the year of approval of the PCSK9 monoclonal antibodies, to the present on the use of PCSK9i not only in the lipid field but also by evaluating their effects on metabolic factors. Results: PCSK9 inhibits cholesterol efflux from macrophages and contributes to the formation of macrophage foam cells. PCSK9 has the ability to bind to Toll-like receptors, thus mediating the inflammatory response and binding to scavenger receptor B/cluster of differentiation 36. PCSK9i lower the entire spectrum of apolipoprotein B-100 containing lipoproteins (LDL, very LDLs, intermediate-density lipoproteins, and lipoprotein[a]) in high CVD-risk patients. Moreover, PCSK9 inhibitors are neutral on risk for new-onset diabetes mellitus and might have a beneficial impact on the development of nonalcoholic fatty liver disease by improving lipid and inflammatory biomarker profiles, steatosis biomarkers such as the triglyceride-glucose index, and hepatic steatosis index, although there are no comprehensive studies with long-term follow-up studies. Conclusion: The discovery of PCSK9i has opened a new era in therapeutic management in patients with hypercholesterolemia and high cardiovascular risk. Increasingly, there has been mounting scientific and clinical evidence supporting the safety and tolerability of PCSK9i.

PCSK9 inhibition and cholesterol homeostasis in insulin producing β-cells

Low-density lipoprotein cholesterol (LDL-C) plays a central role in the pathology of atherosclerotic cardiovascular disease. For decades, the gold standard for LDL-C lowering have been statins, although these drugs carry a moderate risk for the development of new-onset diabetes. The inhibitors of proprotein convertase subtilisin/kexin type 9 (PCSK9) have emerged in the last years as potential alternatives to statins due to their high efficiency and safety without indications for a diabetes risk so far. Both approaches finally eliminate LDL-C from bloodstream by upregulation of LDL receptor surface expression. Due to their low antioxidant capacity, insulin producing pancreatic β-cells are sensitive to increased lipid oxidation and related generation of reactive oxygen species. Thus, PCSK9 inhibition has been argued to promote diabetes like statins. Potentially, the remaining patients at risk will be identified in the future. Otherwise, there is increasing evidence that loss of circulating PCSK9 does not worsen glycaemia since it is compensated by local PCSK9 expression in β-cells and other islet cells. This review explores the situation in β-cells. We evaluated the relevant biology of PCSK9 and the effects of its functional loss in rodent knockout models, carriers of LDL-lowering gene variants and PCSK9 inhibitor-treated patients.

Real-world safety of PCSK9 inhibitors: A pharmacovigilance study based on spontaneous reports in FAERS

Objective: We aimed to evaluate alirocumab- and evolocumab-related adverse events (AEs) in real-world compared with all other drugs, overall and by gender and age subgroups; we also aimed to compare their risks of cognitive impairment, musculoskeletal disorders and diabetes with various statins and ezetimibe. Methods: We retrospectively extracted AE reports from the FDA Adverse Event Reporting System (FAERS) database during July 2015-June 2021. Disproportionality analyses were performed using reporting odds ratios (RORs) to detect AE signals of alirocumab and evolocumab in the overall population and in different age and gender subgroups, respectively. Results: Compared with all other drugs, both alirocumab and evolocumab had a significant signal in "musculoskeletal and connective tissue disorders" (ROR₁ = 2.626, 95% CI 2.552-2.702; ROR2 = 2.575, 95% CI 2.538-2.613). The highest ROR value of 2.311 (95% CI 2.272-2.351) was for "injury, poisoning and procedural complications" and was found in patients aged ≥65 years on evolocumab. The most frequent AEs were "general disorders and administration site conditions" and "musculoskeletal and connective tissue disorders" for all subpopulations. At the preferred term level, the most frequent AE signal was myalgia for alirocumab and injection site pain for evolocumab, overall and by subgroups. Compared with statins/ezetimibe, PCSK9 inhibitors exhibited lower ROR values for adverse events associated with SOC "nervous system disorders", "psychiatric disorders" and "metabolism and nutrition disorders" (all RORs < 1), but mixed results for musculoskeletal disorders. Compared with all other drugs, undocumented AEs, such as acute cardiac event (ROR = 30.0, 95% CI 9.4-95.3) and xanthoma (ROR = 9.3, 95% CI 3.4-25.5), were also reported. Conclusion: Real-world evidence showed that PCSK9 inhibitors were associated with an increased risk of musculoskeletal and connective tissue disorders and general disorders and administration site conditions, overall and by subgroups. Muscle toxicity, injection site reactions, and influenza-like illness were significant AE signals. Compared with various statins and ezetimibe, PCSK9 inhibitors have shown a favorable safety profile in muscle-related events, cognitive impairment and diabetes. Some undocumented AE signals were also reported. Due to the limitations of spontaneous reporting databases, further studies are still needed to establish causality and validate our results.

The role of PCSK9 in NAFLD/NASH and therapeutic implications of PCSK9 inhibition

INTRODUCTION

There are inconsistent findings regarding the effect of lipid-lowering agents on nonalcoholic fatty liver disease (NAFLD). Proprotein Convertase Subtilisin/Kexin type 9 (PCSK9) is an important player in cholesterol homeostasis and intracellular lipogenesis, and PCSK9 inhibitors (PCSK9-i) have been found to be efficient for pharmacological management of hyperlipidemia.

AREAS COVERED

Whether PCSK9 (itself) or PCSK9-i affects NAFLD is still disputed. To address this question, we review published preclinical and clinical studies providing evidence for the role of PCSK9 in and the effect of PCSK9-I on the development and pathogenesis of NAFLD.

EXPERT OPINION

The current evidence from a landscape of preclinical and clinical studies examining the role of PCSK9 in NAFLD shows controversial results. Preclinical studies indicate that PCSK9 associates with NAFLD and nonalcoholic steatohepatitis (NASH) progression in opposite directions. In humans, it has been concluded that the severity of hepatic steatosis affects the correlation between circulating PCSK9 and liver fat content in humans, with a possible impact of circulating PCSK9 in the early stages of NAFLD, but not in the late stages. However, data from clinical trials with PCSK9-i reassure to the safety of these agents, although real-life long-term evidence is needed.

PCSK9 Inhibition and Risk of Diabetes: Should We Worry?

PURPOSE OF REVIEW

Since the clinical benefit of proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors occurs in a setting of reducing low-density lipoprotein-cholesterol (LDL-C) to unprecedentedly low levels, it becomes of interest to investigate possible adverse effects pertaining to the risk of new-onset diabetes (NOD).

RECENT FINDINGS

While safety results reported in either meta-analyses or cardiovascular outcome trials FOURIER (with evolocumab) and ODYSSEY (with alirocumab) did not rise the incidence of NOD, Mendelian randomization analyses were almost concordant in showing an increased risk of NOD. This evidence was in line with post-marketing safety reports highlighting that evolocumab and alirocumab were primarily related to mild hyperglycaemia rather than diabetes, with most of the hyperglycaemic events occurring during the first 6 months of treatment. Considering the different nature of genetic studies and of randomized controlled trials, with careful monitoring of patients, particularly in the earlier phases of treatment, and the identification of those more susceptible to develop NOD, treatment with PCSK9 inhibitors should be of minimal concern.