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

Targeting Allosteric Site of PCSK9 Enzyme for the Identification of Small Molecule Inhibitors: An In Silico Drug Repurposing Study

The primary cause of atherosclerotic cardiovascular disease (ASCVD) is elevated levels of low-density lipoprotein cholesterol (LDL-C). Proprotein convertase subtilisin/kexin type 9 (PCSK9) plays a crucial role in this process by binding to the LDL receptor (LDL-R) domain, leading to reduced influx of LDL-C and decreased LDL-R cell surface presentation on hepatocytes, resulting higher circulating levels of LDL-C. As a consequence, PCSK9 has been identified as a crucial target for drug development against dyslipidemia and hypercholesterolemia, aiming to lower plasma LDL-C levels. This research endeavors to identify promising inhibitory candidates that target the allosteric site of PCSK9 through an in silico approach. To start with, the FDA-approved Drug Library from Selleckchem was selected and virtually screened by docking studies using Glide extra-precision (XP) docking mode and Smina software (Version 1.1.2). Subsequently, rescoring of 100 drug compounds showing good average docking scores were performed using Gnina software (Version 1.0) to generate CNN Score and CNN binding affinity. Among the drug compounds, amikacin, bestatin, and natamycin were found to exhibit higher docking scores and CNN affinities against the PCSK9 enzyme. Molecular dynamics simulations further confirmed that these drug molecules established the stable protein-ligand complexes when compared to the apo structure of PCSK9 and the complex with the co-crystallized ligand structure. Moreover, the MM-GBSA calculations revealed binding free energy values ranging from -84.22 to -76.39 kcal/mol, which were found comparable to those obtained for the co-crystallized ligand structure. In conclusion, these identified drug molecules have the potential to serve as inhibitors PCSK9 enzyme and these finding could pave the way for the development of new PCSK9 inhibitory drugs in future in vitro research.

Unraveling Potential Sex-Specific Effects of Cardiovascular Medications on Longevity Using Mendelian Randomization

BACKGROUND

Establishing the sex-specific efficacy of cardiovascular medications is pivotal to evidence-based clinical practice, potentially closing the gender gap in longevity. Trials large enough to establish sex differences are unavailable. This study evaluated sex-specific effects of commonly prescribed cardiovascular medications on lifespan.

METHODS AND RESULTS

In a two-sample Mendelian randomization study, established genetic variants mimicking effects of lipid-lowering drugs, antihypertensives, and diabetes drugs were applied to genetic associations with lifespan proxied by UK Biobank maternal (n=412 937) and paternal (n=415 311) attained age. Estimates were obtained using inverse variance weighting, with sensitivity analyses where possible. For lipid-lowering drugs, genetically mimicked PCSK9 (proprotein convertase subtilisin/kexin type 9) inhibitors were associated with longer lifespan, particularly in men (2.39 years per SD low-density lipoprotein cholesterol reduction [95% CI, 0.42-4.36], P for interaction=0.14). Genetically mimicked treatments targeting APOC3, LPL, or possibly LDLR were associated with longer lifespan in both sexes. For antihypertensives, genetically mimicked β-blockers and calcium channel blockers were associated with longer lifespan, particularly in men (P for interaction=0.17 for β-blockers and 0.31 for calcium channel blockers). For diabetes drugs, genetically mimicked metformin was associated with longer lifespan in both sexes. No associations were found for genetically mimicked statins, ezetimibe, or angiotensin-converting enzyme inhibitors.

CONCLUSIONS

PCSK9 inhibitors, β-blockers, and calcium channel blockers may prolong lifespan in the general population, particularly men. Treatments targeting APOC3, LPL, or LDLR and metformin may be relevant to both sexes. Whether other null findings are attributable to lack of efficacy requires investigation. Further investigation of repurposing should be conducted.

Sex differences in efficacy and safety of PCSK9 monoclonal antibodies: A real-world registry

BACKGROUND AND AIMS

Proprotein convertase subtilisin/kexin 9 monoclonal antibodies (PCSK9 mAbs) reduce low-density lipoprotein (LDL-c) with a favourable safety profile. Available data from PCSK9 antibody trials suggest LDL-c reduction is lower in women compared to men. Data in real-world setting is scarce. The aim of this study was to assess sex differences in efficacy and safety of PCSK9 antibodies in clinical care.

METHODS

All patients starting with evolocumab or alirocumab in our lipid clinic were included in a prospective registry. We collected clinical information, including baseline and follow-up mean LDL-C levels after initiation of PCSK9 mAbs treatment. In addition, side effects and PCSK9 mAbs discontinuation were recorded.

RESULTS

We analysed 436 patients (209 women), mean age 58 ± 11 years. Women had higher baseline LDL-c levels compared to men (4.7 ± 1.6 mmol/L vs 4.1 ± 1.4 mmol/L, p < 0.01). PCSK9 mAbs resulted in less relative LDL-c reduction in women compared to men (50% vs 61% p<0.01), but equal absolute LDL-c reduction (respectively 2.3 ± 1.3 mmol/L vs 2.5 ± 1.1 mmol/L, p = 0.087). Women less often reached LDL-c target levels than men (50% vs 72%). No sex differences were observed in reporting of side effects (women 32% vs men 27% p = 0.26) or PCSK9 mAbs discontinuation (women 13% vs men 10%, p = 0.46).

CONCLUSIONS

In clinical practice, PCSK9 mAbs are less effective in reducing LDL-c levels in women compared to men and equally safe, implying the importance of sex differences in PCSK9 metabolism.

Major cardiovascular events increase in long-term proprotein convertase subtilisin/kexin type 9 inhibitors therapy: the Tuscany cost-effective study

BACKGROUND

Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) represent a breakthrough in the treatment of hypercholesterolemia. The aim of this study was to perform a multicentre prospective analysis on the effects of PCSK9i since their distribution in Italy.

METHODS

During the study period (July 2017 to February 2022) 246 patients (mean age 61 ± 11 years, male 73%) who were evolocumab (142/246) or alirocumab (104/246) new users were enrolled in the CERTI (Costo Efficacia Regione Toscana Inibitori PCSK9) study. Lipid value, adverse events (AEs), major cardiovascular events (MACEs) and intima-media thickness were analysed.

RESULTS

PCSK9i therapy allowed a significant improvement in patients' lipid profile [total cholesterol -35%, P < 0.001; triglycerides -9%, P < 0.05; low-density lipoprotein (LDL) cholesterol -51%, P < 0.001; Lp(a) levels -4%, P < 0.05], maintained during the follow-up. No significant variations in intima-media thickness were observed. In the subgroup of patients with more than 1 year of PCSK9i therapy (165/246 patients) we highlighted: a 66% reduction in MACEs compared with the year before recruitment; a progressive increase in MACEs during the follow-up (MACEs event/rate at first year 0.08 vs. MACEs event/rate at year 5: 0.47); a patients cluster with late MACEs older, with higher prevalence of hypertension, smoking habit and peripheral vascular disease. During the follow-up, we recorded AEs in 31% of patients, which mainly resulted in reduction/discontinuation of lipid-lowering therapy for 50 patients or in discontinuation/shift of PCSK9i (respectively 8 and 6 cases).

CONCLUSION

Our data agree with the large evidence on the effectiveness/tolerability of PCSK9i therapy; however, although PCSK9i represents a good cholesterol-lowering therapeutic option, our study shows a progressive increase in MACEs during the late follow-up that deserve further research.

Efficacy, safety, adherence and persistence of PCSK9 inhibitors in clinical practice: A single country, multicenter, observational study (AT-TARGET-IT)

BACKGROUND AND AIMS

Proprotein Convertase Subtilisin/Kexin type 9 inhibitors (PCSK9i) are recommended in patients at high and very-high cardiovascular (CV) risk, with documented atherosclerotic CV disease (ASCVD), and for very-high risk patients with familial hypercholesterolaemia not achieving LDL-cholesterol (LDL-C) goal while receiving maximally tolerated dose of lipid-lowering therapy (LLT). However, single country real-life data, reporting the use of PCSK9i in clinical practice, are limited. Therefore, we designed AT-TARGET-IT, an Italian, multicenter, observational registry on the use of PCSK9i in clinical practice.

METHODS

All data were recorded at the time of the first prescription and at the latest observation preceding inclusion in the study.

RESULTS

798 patients were enrolled. The median reduction in LDL-C levels was 64.9%. After stratification for CV risk, 63.8% achieved LDL-C target; of them, 83.3% took LLTs at PCSK9i initiation and 16.7% did not. 760 patients (95.2%) showed high adherence to therapy, 13 (1.6%) partial adherence, and 25 (3.1%) poor adherence. At 6 months, 99.7% of patients enrolled in the study remained on therapy; there were 519 and 423 patients in the study with a follow-up of at least 12 and 18 months, respectively. Persistence in these groups was 98.1% and 97.5%, respectively. Overall, 3.5% of patients discontinued therapy. No differences in efficacy, adherence, and persistence were found between alirocumab and evolocumab.

CONCLUSIONS

PCSK9i are safe and effective in clinical practice, leading to very high adherence and persistence to therapy, and achievement of recommended LDL-C target in most patients, especially when used as combination therapy.

Mechanisms of unusual response to lipid-lowering therapy: PCSK9 inhibition

The efficacy of proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition has broadened lipid-lowering therapy thus providing decreased risk in atherosclerotic cardiovascular disease. Unfortunately, the widespread use of PCSK9 inhibitors (PCSK9i), ie, monoclonal antibodies, has led to the findings of unusual responsiveness, ie, a phenomenon defined as an LDL-C reduction of <30% vs the average LDL-C reduction efficacy of 50-60%. This unusual responsiveness to PCSK9i is attributable to several factors, ie, lack of adherence, impaired absorption, poor distribution or early elimination as well as abnormal effects of PCSK9i in the presence of anti-antibodies or mutations in PCSK9 and LDLR. Unexpectedly increased lipoprotein (Lp)(a) also appear to contribute to the unusual responsiveness scenario. Identification of these responses and mechanisms underlying them are essential for effective management of LDL-C and cardiovascular risk. In this review, we describe plausible reasons underlying this phenomenon supported by findings of clinical trials. We also elaborate on the need for education and regular follow-up to improve adherence. Collectively, the review provides a summary of the past, present, and future of mechanisms and countermeasures revolving around unusual responses to PCSK9i therapy.

Effect of alirocumab and evolocumab on all-cause mortality and major cardiovascular events: A meta-analysis focusing on the number needed to treat

AIMS

The efficacy of anti-proprotein convertase subtilisin/Kexin type 9 (PCSK9) monoclonal antibodies in patients with atherosclerotic cardiovascular disease (ASCVD) remains unclear. Therefore, this study aims to assess the effect of PCSK9 inhibitors (alirocumab and evolocumab) on ASCVD patients considering the number needed to treat (NNT).

METHODS

We reviewed randomized controlled trials (RCTs) which compared the effects of alirocumab or evolocumab and placebo or standards of care. All articles were published in English up to May 2022. Using random effect models, we estimated risk ratios (RRs), NNT, and 95% confidence intervals (CI).

RESULTS

We incorporated 12 RCTs with 53 486 patients total, of which 27 674 received PCSK9 inhibitors and 25 812 received placebos. The mean follow-up duration was 1.56 years. The effect of PCSK9 inhibitors on major adverse cardiovascular events (MACE) was statistically significant, and the corresponding mean NNT was 36. Alirocumab reduced the risk of MACE, stroke, and coronary revascularization; the corresponding mean NNT were 37, 319, and 107, respectively. Evolocumab positively affected MACE, myocardial infarction, stroke, and coronary revascularization; the corresponding mean NNT were 32, 78, 267, and 65, respectively. The effects of alirocumab or evolocumab on all-cause mortality and cardiovascular mortality were not statistically significant.

CONCLUSION

This study suggests that preventing one patient from MACE needed to treat 36 patients with ASCVD with PCSK9 inhibitors for 1.56 years. Both alirocumab and evolocumab reduced MACE, stroke, and coronary revascularization. Evolocumab had a positive effect on myocardial infarction, but no effects were noted for alirocumab. In addition, alirocumab may not be as effective as evolocumab. NNT visualizes the magnitude of efficacy to assist in clinical decisions.

SYSTEMATIC REVIEW REGISTRATION

[https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=344908], identifier [CRD42022344908].

A subgroup analysis of the ODYSSEY APPRISE study: Safety and efficacy of alirocumab in the Italian cohort

BACKGROUND AND AIMS

ODYSSEY APPRISE trial evaluated efficacy and safety of alirocumab in 994 patients with hypercholesterolemia and high CV risk in a real-life setting. The aim of the present report is to detail on the Italian cohort enrolled and treated in the trial.

METHODS AND RESULTS

The methodology of the of the multinational, single-arm, Phase 3b open-label ODYSSEY APPRISE (Clinicaltrials.gov: NCT02476006) has been previously reported. 255 Italian patients were enrolled and treated according to the trial protocol. Overall mean exposure to alirocumab was 83.3 ± 27.7 weeks. At week 12, LDL-C decreased by 51.3 ± 23.1% and this reduction was overall maintained for the duration of the study. A similar reduction was observed in patients with and without heterozygous familial hypercholesterolemia (HeFH 50.7% ± 23.9 vs. non-FH, 53.6% ± 19.6). LDL-C was reduced below 1.8 mmol/L and/or by ≥ 50% reduction from baseline in 62% of patients overall (61% in HeFH and 67% in non-FH). Alirocumab was similarly well tolerated in the Italian cohort as in the entire study population and the more common treatment emergent adverse events (TEAEs) were influenza, myalgia and nasopharyngitis. The incidence LDL-C levels <25 mg/dl and <15 mg/dl, was 8.2% and 2.9% respectively.

CONCLUSION

The efficacy and safety of alirocumab in a real-life setting, in the Italian subgroup of patients are consistent with findings in the entire study population and confirm that alirocumab is a beneficial approach to further reduce LDL-C levels in patients at high CV risk on maximally tolerated conventional lipid lowering treatment.

GOV IDENTIFIER

NCT02476006.