PCSK9 Inhibitors

BackgroundLowering of atherogenic lipoproteins, including low-density lipoprotein cholesterol (LDL-C), reduces the risk of ischemic stroke. However, concerns have been raised about very low LDL-C levels and a potential increased risk of hemorrhagic stroke. ODYSSEY OUTCOMES compared the PCSK9 inhibitor alirocumab with placebo in 18 924 patients with recent acute coronary syndrome and elevated atherogenic lipoproteins, despite intensive statin therapy, targeting LDL-C levels of 25 to 50 mg/dL and avoiding sustained LDL-C MethodsPatients were randomized to alirocumab or placebo 1 to 12 months after acute coronary syndrome. The risk of nonfatal or fatal ischemic or hemorrhagic stroke was evaluated, stratified by baseline LDL-C concentration and history of cerebrovascular disease. A potential association of very low achieved LDL-C with alirocumab treatment at month 4 and subsequent hemorrhagic stroke was assessed.ResultsMedian follow-up was 2.8 years. In total, 263 ischemic and 33 hemorrhagic strokes occurred. Alirocumab reduced the risk of any stroke (HR, 0.72 [95% CI, 0.57-0.91]) and ischemic stroke (HR, 0.73 [95% CI, 0.57-0.93]) without increasing hemorrhagic stroke (HR, 0.83 [95% CI, 0.42-1.65]). In total, 7164 (37.9%), 6128 (32.4%), and 5629 (29.7%) patients had a baseline LDL-C of 100 mg/dL, respectively. The treatment effect on stroke appeared numerically greater for patients with higher baseline LDL-C, but there was no formal evidence of heterogeneity (Pinteraction=0.31). The effect of alirocumab on stroke was similar among 944 patients (5.0%) with a history of previous cerebrovascular disease and among those without a history of cerebrovascular disease (Pinteraction=0.37). There was no apparent adverse relation between lower achieved LDL-C and incidence of hemorrhagic stroke in the alirocumab group.ConclusionsIn patients with recent acute coronary syndrome and dyslipidemia despite intensive statin therapy, alirocumab decreased the risk of stroke, irrespective of baseline LDL-C and history of cerebrovascular disease, over a median follow-up of 2.8 years. Furthermore, risk of hemorrhagic stroke did not depend on achieved LDL-C levels within the alirocumab group.Clinical trial registrationURL: https://www.clinicaltrials.gov. Unique identifier: NCT01663402.

BackgroundRecent international guidelines have lowered recommended target levels of low-density lipoprotein cholesterol (LDL-C) for patients at very high risk for major adverse cardiovascular events (MACE). However, uncertainty persists whether additional benefit results from achieved LDL-C levels below the conventional targets. Inferences from previous analyses are limited because patients who achieve lower versus higher LDL-C on lipid-lowering therapy differ in other characteristics prognostic for MACE and because few achieved very low LDL-C levels. To overcome these limitations, we performed a propensity score-matching analysis of the ODYSSEY OUTCOMES trial (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab) which compared alirocumab with placebo in 18 924 patients with recent acute coronary syndrome receiving intensive or maximum-tolerated statin treatment.MethodsPatients on alirocumab were classified in prespecified strata of LDL-C achieved at 4 months of treatment: 50 mg/dL (n=2197). For each stratum, MACE (coronary heart disease death, nonfatal myocardial infarction, ischemic stroke, or hospitalization for unstable angina) after month 4 was compared in patients receiving placebo with similar baseline characteristics and adherence by using 1:1 propensity score matching.ResultsAcross achieved LDL-C strata of the alirocumab group, patients differed by baseline LDL-C, lipoprotein(a), use of intensive statin therapy, study medication adherence, and other demographic, medical history, biometric, and laboratory criteria. After propensity score matching, characteristics were similar in corresponding patients of the alirocumab and placebo groups. Treatment hazard ratio, 95% CI, and absolute risk reduction (number per 100 patient-years) for MACE were similar in those with achieved LDL-C 50 mg/dL had poorer adherence and derived less benefit (hazard ratio, 0.87 [95% CI, 0.73-1.04]; absolute risk reduction, 0.62). No safety concerns were associated with a limited period of LDL-C levels ConclusionsAfter accounting for differences in baseline characteristics and adherence, patients treated with alirocumab who achieved LDL-C levels <25 mg/dL had a reduction in the risk of MACE that was similar to that of patients who achieved LDL-C levels of 25 to 50 mg/dL. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01663402.

Genetic, epidemiological and pharmacological data have led to the conclusion that antagonizing or inhibiting Proprotein convertase subtilisin/kexin type 9 (PCSK9) reduces cardiovascular events. This clinical outcome is mainly related to the pivotal role of PCSK9 in controlling low-density lipoprotein (LDL) cholesterol levels. The absence of oral and affordable anti-PCSK9 medications has limited the beneficial effects of this new therapeutic option. A possible breakthrough in this field may come from the discovery of new naturally occurring PCSK9 inhibitors as a starting point for the development of oral, small molecules, to be used in combination with statins in order to increase the percentage of patients reaching their LDL-cholesterol target levels. In the present review, we have summarized the current knowledge on natural compounds or extracts that have shown an inhibitory effect on PCSK9, either in experimental or clinical settings. When available, the pharmacodynamic and pharmacokinetic profiles of the listed compounds are described.

Background and aimsLow-density lipoprotein cholesterol (LDL-C)-lowering therapies are proven effective in atherosclerotic cardiovascular disease (ASCVD), but real-world evidence for proprotein convertase subtilisin/kexin type 9 inhibitor (PCSK9i) monoclonal antibodies (mAb) remains limited. This study evaluated their impact in patients with ASCVD without prior ischaemic events.MethodsPatients initiating PCSK9i mAb from January 2016 to December 2022 were identified in the Optum Research Database. A 1:2 propensity score-matched comparator cohort of PCSK9i non-initiators was developed. The primary endpoint was a composite of non-fatal myocardial infarction, non-fatal ischaemic stroke, or all-cause mortality. Key outcomes from the parametric G-formula were 5-year event rates, relative risk reduction (RRR) and absolute risk reduction (ARR), with intention-to-treat (ITT) analysis. Additional outcomes for PCSK9i mAb initiators included absolute and percent LDL-C reduction from baseline.ResultsOverall, 19 670 patients met selection criteria (6545 PCSK9i mAb initiators; 13 125 non-initiators). Baseline characteristics were well-balanced. Under ITT, estimated 5-year event rates were 17.5% [95% confidence interval (CI) 15.5%, 19.5%] with PCSK9i mAb vs 25.4% (95% CI 23.6%, 27.1%) without PCSK9i, yielding a RRR of 30.9% and ARR of 7.8%. Individual endpoints showed RRRs of 28.3% for myocardial infarction (P ConclusionsIn ASCVD patients without prior events in clinical practice, PCSK9i mAb treatment was associated with lower ischaemic event and mortality rates.