Efficacy of PCSK9 inhibitors in the treatment of heterozygous familial hypercholesterolemia: A clinical practice experience

Long-Term Efficacy and Tolerability of PCSK9 Targeted Therapy: A Review of the Literature

Increased plasma levels of low-density lipoprotein cholesterol (LDL-C) are causally associated with atherosclerotic cardiovascular disease (ASCVD), and statins that lower LDL-C have been the cornerstone of ASCVD prevention for decades. However, guideline-recommended LDL-C targets are not achieved in about 60% of statin users. Proprotein convertase subtilisin/kexin type 9 (PCSK9)-targeted therapy effectively lowers LDL-C levels and has been shown to reduce ASCVD risk. A growing body of scientific and clinical evidence shows that PCSK9-targeted therapy offers an excellent safety and tolerability profile with a low incidence of side effects in the short term. In this review, we present and discuss the current clinical and scientific evidence pertaining to the long-term efficacy and tolerability of PCSK9-targeted therapy.

Novel Insights into the Management of Patients with Very High Cardiovascular Risk Eligible for PCSK9 Inhibitor Treatment: Baseline Findings from the PERI-DYS Study

AIM

The PERI-DYS study aims to characterize two groups of patients with dyslipidaemia at very high CV risk: PCSK9i receivers and patients qualifying for but not receiving PCSK9i.

METHODS

This is an observational study by office-based and clinic-based physicians, mainly cardiologists and other internists in Germany, with data extracted from patient charts.

CLINICALTRIALS

gov identifier NCT03110432.

RESULTS

A total of 1659 patients were enrolled across 70 sites. The majority of patients (91.0%) were reported as having mixed dyslipidaemia or non-familial or heterozygous familial hypercholesterolemia. At enrolment, 794 (47.9%) of patients were PCSK9i receivers (of these 65.9% ongoing, and 34.1% newly treated within 30 days before their baseline visit). Among PCSK9i receivers, the majority had evolocumab 140 mg (n = 632, 38.1% of total). PCSK9i receivers compared to non-receivers were about 2 years younger and had a lower proportion of males. In terms of comorbidities, they had (statistically significantly) more often CAD, and less often PAD, diabetes mellitus, arterial hypertension and chronic renal disease. The calculated untreated median LDL-C was 187 mg/dl (IQR 127; 270) in ongoing PCSK9i receivers, 212 mg/dl (IQR 132; 277) in newly treated PCSK9i receivers, and 179 mg/dl (IQR 129; 257) in non-receivers. Physician-reported statin intolerance was much more common in the two PCSK9i receiver groups as compared to non-receivers (67.3% versus 15.3%). Consequently, patients in the PCSK9i groups received fewer concomitant statins. Mean total cholesterol (143 vs. 172 mg/dl) and LDL-C (69 vs. 99 mg/dl) were considerably lower in ongoing PCSK9i receivers compared to non-receivers.

CONCLUSIONS

PCSK9i receivers are characterized by higher baseline LDL-C and a higher portion of statin intolerance compared to those qualified for but not-receiving PCSK9i treatment. On-treatment, LDL-C was lower in PCSK9i receivers. Ongoing follow-up will determine the prognostic importance of these findings.

Observational study of patients from a Lipid Unit on lipid-modifying therapy for primary and secondary prevention: ULFI Study

OBJECTIVES

To evaluate the achievement of low-density lipoprotein cholesterol (LDLc) goals established by the 2019 European Guidelines for the Management of Dyslipidemias and 2021 Cardiovascular Disease Prevention Guidelines, describe the lipid-lowering treatment received, analyze the achievement of goals according to the lipid-lowering treatment received and study the factors associated with therapeutic success.

DESIGN

Observational study that included 185 patients of both sexes aged 18 or over undergoing lipid-lowering treatment for primary or secondary prevention, attended at the Lipid Unit.

RESULTS

62.1% of the patients had a very high cardiovascular risk (CVR) according to the 2019 guidelines, and 60.5% according to the 2021 guidelines. Of the total cases, 22.7% achieved adequate control of LDLc according to the 2019 guidelines and 20% according to the 2021 guidelines. 47.6% of the patients received very high intensity lipid-lowering treatment, and 14.1% received extremely high intensity lipid-lowering treatment. 76% of subjects with very high CVR on extremely high intensity lipid-lowering treatment achieved the therapeutic objectives of both guides. In the multivariate analysis, factors associated with therapeutic success were the presence of arteriosclerotic cardiovascular disease, the intensity of lipid-lowering treatment, diabetes mellitus, and low to moderate alcohol consumption.

CONCLUSIONS

Dyslipidemia control is improvable. High or extremely high intensity lipid-lowering treatments can contribute to optimizing control of patients with higher CVR.

Alirocumab and Coronary Atherosclerosis in Asymptomatic Patients with Familial Hypercholesterolemia: The ARCHITECT Study

BACKGROUND

The effect of alirocumab, a PCSK9 (proprotein convertase subtilisin/kexin type 9) inhibitor, on coronary plaque burden in patients with familial hypercholesterolemia has not been addressed. Our aim was to assess changes in coronary plaque burden and its characteristics after treatment with alirocumab by quantification and characterization of atherosclerotic plaque throughout the coronary tree on the basis of a noninvasive analysis of coronary computed tomographic angiography in asymptomatic subjects with familial hypercholesterolemia receiving optimized and stable treatment with maximum tolerated statin dose with or without ezetimibe.

METHODS

This study is a phase IV, open-label, multicenter, single-arm clinical trial to assess changes in coronary plaque burden and its characteristics after 78 weeks of treatment with alirocumab in patients with familial hypercholesterolemia without clinical atherosclerotic cardiovascular disease. Participants underwent an initial coronary computed tomographic angiography at baseline and another at 78 weeks. Every patient received 150 mg of alirocumab subcutaneiously every 14 days in addition to high-intensity statin therapy. The main outcome was the change on coronary plaque burden and its characteristics by quantification and characterization of atherosclerotic plaque throughout the coronary tree on the basis of analysis of coronary computed tomographic angiography.

RESULTS

The study was completed by 104 patients. The median age was 53.3 (46.2-59.4) years. Of these patients, 54 were women (51.9%). Median low-density lipoprotein cholesterol was 138.9 (117.5-175.3) mg/dL at entry and 45.0 (36.0-65.0) mg/dL at follow-up (P<0.001). Coronary plaque burden changed from 34.6% (32.5%-36.8%) at entry to 30.4% (27.4%-33.4%) at follow-up (P<0.001). A significant change in the characteristics of the coronary atherosclerosis was also found: an increase in the proportion of calcified (+0.3%; P<0.001) and mainly fibrous (+6.2%; P<0.001) plaque, accompanied by a decrease in the percentage of fibro-fatty (-3.9%; P<0.001) and necrotic plaque (-0.6%; P<0.001).

CONCLUSIONS

Treatment with alirocumab in addition to high-intensity statin therapy resulted in significant regression of coronary plaque burden and plaque stabilization on coronary computed tomographic angiography over 78 weeks in these groups of patients with familial hypercholesterolemia without clinical atherosclerotic cardiovascular disease. ARCHITECT (Effect of Alirocumab on Atherosclerotic Plaque Volume, Architecture and Composition) could link and explain ODYSSEY OUTCOMES (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab) results.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT05465278.

Persistence with long-term PCSK9 inhibitor treatment and its effectiveness in familial hypercholesterolaemia: data from the SAFEHEART study

AIMS

Most heterozygous familial hypercholesterolaemia (FH) patients require intensive lipid-lowering therapy (LLT) including PCSK9 inhibitors (PCSK9is) to reach current low-density lipoprotein cholesterol (LDL-C) goals. Persistence with chronic treatment is important to reduce the burden of atherosclerotic cardiovascular disease. We analysed persistence, efficacy, and impact on quality of life (QoL) of PCSK9i in FH patients in clinical practice setting.

METHODS AND RESULTS

Spanish Familial Hypercholesterolaemia Cohort Study (SAFEHEART) is an open, prospective study in genetically defined FH patients in Spain. Patients ≥18 years of age (n = 696, 46% females) on stable LLT treated with PCSK9i were analysed. Median LDL-C at starting PCSK9i was 145 mg/dL [interquartile range (IQR), 123-177], 3.8 mmol/L (IQR 3.2-4.6). After a median follow up of 3.7 years (IQR 2.3-4.8), 27 patients (4%) discontinued PCSK9i treatment: 5 temporarily (0.7%) and 22 permanently (3.2%). Persistence with PCSK9i was 96.1% in the whole period. Median LDL-C levels and % LDL-C reduction attained after 1 year of treatment and in the last follow-up visit were 63 mg/dL (IQR 43-88), 1.6 mmol/L (IQR 1.1-2.23); 61 mg/dL (IQR 44-82), 1.6 mmol/L (IQR 1.1-2.1); 57.6% (IQR 39.5-69); and 58% (IQR 44-68), respectively. 2016 and 2019 ESC/EAS LDL-C goals were attained by 77 and 48% of patients, respectively, at the last follow-up visit (P < 0.001). Mean QoL score increased slightly in the first year and remained stable.

CONCLUSION

Long-term persistence with PCSK9i in FH patients is very high, with a good QoL. Effectiveness in LDL-C reduction and LDL-C goal achievement dramatically improved with PCSK9i in this high-risk population in clinical practice setting.

TRIAL REGISTRATION

ClinicalTrials.gov number NCT02693548.

Association of PCSK9 Loss-of-Function Variants With Risk of Heart Failure

Importance

An animal (mouse) study indicated that deficiency of proprotein convertase subtilisin/kexin type 9 (PCSK9) causes cardiac remodeling and heart failure (HF). Cardiac remodeling after PCSK9-inhibitor treatment is a concern for patients and for development of treatment directed against PCSK9.

Objective

To determine whether genetic variants in the PCSK9 gene are associated with altered cardiac structure, cardiac function, and HF in humans.

Design, Setting, Participants

This was a nested case-control study within the UK Biobank. Between March 13, 2006, and October 1, 2010, the UK Biobank enrolled 502 480 individuals aged 40 to 69 years. This study focused on a subset of those individuals, who completed cardiac magnetic resonance (CMR) imaging and had available genetic data. Analyses were conducted between November 2, 2021, and October 28, 2022.

Exposures

Carrier status of predicted loss-of-function (pLoF) PCSK9 variants, R46L missense variant, and a genetic risk score (GRS).

Main Outcomes and Measures

A total of 11 CMR imaging measurements, generated using a machine learning algorithm, and HF diagnosis.

Results

In up to 35 135 individuals with CMR images, 18 252 (52%) were female individuals, and mean (SD) age was 55.0 (7.4) years. No significant association between PCSK9 carrier status and CMR indices were found for left ventricular mass (pLoF: β = -1.01; 95% CI, -2.99 to 0.98; P = .32; R46L: β = -0.18; 95% CI, -0.55 to 0.19; P = .35; GRS: β = -0.19; 95% CI, -0.50 to 0.11; P = .22) and left ventricular ejection fraction (pLoF: β = 0.43; 95% CI, -1.32 to 2.18; P = .63; R46L: β = -0.19; 95% CI, -0.52 to 0.14; P = .26; GRS: β = -0.08; 95% CI, -0.35 to 0.20; P = .58) or HF (pLoF: odds ratio [OR], 1.14; 95% CI, 0.56-2.05; P = .69; R46L: OR, 0.99; 95% CI, 0.90-1.10; P = .91; GRS: OR, 1.04; 95% CI, 0.96-1.13; P = .32).

Conclusions and Relevance

Results of this case-control study suggest that there was no association between PCSK9 genetic variants and altered cardiac structure, cardiac function, or HF in humans.

Sex differences in LDL-C response to PCSK9 inhibitors: A real world experience

BACKGROUND

Previous studies have shown the efficacy of PCSK9 inhibitors (PCSK9i) in lowering LDL-C. One clinical trial with alirocumab suggested that the LDL-C reduction effect is larger in men than women. In contrast, none of the studies with evolocumab have observed a difference in the treatment effect between men and women. However, sex differences data from real life experience is lacking. In addition, the difference in LDL-C response to PCSK9i between pre- and post-menopausal women has not been investigated so far.

OBJECTIVES

To compare the relative change in LDL-C following the introduction of a PCSK9i in a real-life clinical setting according to sex and menopausal status.

METHODS

All patients were recruited at the IRCM lipid clinic. Lipid profiles before and after the introduction of PCSK9i were available in the medical file for 259 patients (160 men and 99 women (72 post-menopausal, 20 pre-menopausal and 7 unknown menopausal status).

RESULTS

We observed a significant difference in relative LDL-C change between men (-70%) and women (-59%), p<0.0001. However, no difference was observed between pre-menopausal (-58%) and post-menopausal (-58%) women. In a linear regression model, sex remains a significant predictor of the response to PCSK9i after correction for confounding factors such as statin intensity (beta coefficient=-0.245, p<0.0001).

CONCLUSION

We observed a greater relative LDL-C response to PCSK9i in men than in women in a real-life clinical context. However, it is still unknown whether this difference in LDL-C change between men and women translates into a meaningful difference on long-term cardiovascular risk.

Familial Hypercholesterolemia and Lipoprotein(a): Two Partners in Crime?

PURPOSE OF REVIEW

Familial hypercholesterolemia is a high cardiovascular risk disorder. We will review the role of lipoprotein(a) in cardiovascular risk and in aortic valve stenosis in familial hypercholesterolemia, as well as its association with their phenotype, and strategies to identify this high-risk population.

RECENT FINDINGS

Patients with familial hypercholesterolemia have higher lipoprotein(a) levels mainly due to an increased frequency of LPA variants, and the cardiovascular risk is increased twofolds when both conditions coexist. Also, an increased risk for aortic valve stenosis and valve replacement has been observed with high lipoprotein(a) levels. Assessment of lipoprotein(a) during the cascade screening for familial hypercholesterolemia is a good opportunity to identify this high-risk population. High cardiovascular risk in familial hypercholesterolemia is increased even more when lipoprotein(a) is also elevated. Measurement of lipoprotein(a) in these patients is crucial to identify those subjects who need to intensify LDL-cholesterol reduction pending availability of lipoprotein(a)-specific treatments.

A resilient type of familial hypercholesterolaemia: case-control follow-up of genetically characterized older patients in the SAFEHEART cohort

AIMS 

Knowledge of the features of patients with familial hypercholesterolaemia (FH) who are protected from atherosclerotic cardiovascular disease (ASCVD) is important for the clinical and prognostic care of this apparently high-risk condition. Our aim was to investigate the determinant and characteristics of patients with FH who are protected from ASCVD and have normal life expectancy, so-called 'resilient' FH (R-FH).

METHODS AND RESULTS 

Spanish Familial Hypercholesterolaemia cohort study (SAFEHEART) is an open, multicentre, nation-wide, long-term prospective cohort study in genetically defined patients with heterozygous FH in Spain. Patients in the registry who at the time of analysis were at least 65 years or those who would have reached that age had they not died from an ASCVD event were analysed as a case-control study. Resilient FH was defined as the presence of a pathogenic mutation causative of FH in a patient aged ≥65 years without clinical ASCVD. Nine hundred and thirty registrants with FH met the study criteria. A defective low-density lipoprotein (LDL)-receptor mutation, higher plasma level of high-density lipoprotein cholesterol (HDL-C), younger age, female gender, absence of hypertension, and lower plasma lipoprotein (a) [Lp(a)] concentration were independently predictive of R-FH. In a second model, higher levels of HDL-C and lower 10-year score in SAFEHEART-RE were also independently predictive of R-FH.

CONCLUSION 

Resilient FH may be typified as being female and having a defective LDL-receptor mutation, higher levels of plasma HDL-C, lower levels of Lp(a), and an absence of hypertension. The implications of this type of FH for clinical practice guidelines and the value for service design and optional care of FH remains to be established.

TRIAL REGISTRATION

ClinicalTrials.gov number NCT02693548.

Past, Present, and Future of Familial Hypercholesterolemia Management

Familial hypercholesterolemia (FH) is a monogenic form of severe hypercholesterolemia that, if left untreated, is associated with early onset of atherosclerosis. FH derives from genetic variants that lead to inefficient hepatic clearance of low-density lipoprotein (LDL) particles from the circulation. The FH phenotype is encountered in approximately 1 of every 300 people. The risk of atherosclerotic cardiovascular disease (ASCVD) is higher in those with FH than in normolipidemic individuals and in those with polygenic hypercholesterolemia. FH is usually diagnosed by clinical scores that consider hypercholesterolemia, family history of early ASCVD and hypercholesterolemia, and cutaneous stigmata. Genetic diagnosis is important and should be offered to individuals suspected of FH. Family cascade screening is important to identify asymptomatic hypercholesterolemic individuals. Despite the high risk of ASCVD, this risk is heterogenous in heterozygous FH and depends not only on high LDL cholesterol (LDL-C) but also on other risk biomarkers. Risk can be evaluated by considering biomarkers such as male sex, late-onset therapy (> age 40), LDL-C > 310 mg/dL, low high-density lipoprotein cholesterol, elevated lipoprotein(a), obesity, diabetes, and hypertension by using specific risk equations and by detecting subclinical coronary atherosclerosis. Statins are the main therapy for FH and change the natural history of ASCVD; however, most individuals persist with elevated LDL-C. PCSK9 inhibitors provide robust and safe LDL-C lowering in FH, although elevated costs preclude their widespread use. Newer therapies such as ANGPTL3 inhibitors add intensive LDL-C lowering for refractory forms of FH. Finally, while it is possible to normalize LDL-C in people with FH, the disease unfortunately is still severely underdiagnosed and undertreated.