Proprotein convertase subtilisin/kexin type 9: From genetics to clinical trials

Purpose of review This review describes the pivotal role of genetic insights and technologies in the discovery of proprotein convertase subtilisin/kexin type 9 (PCSK9) and the rapid development of PCSK9 inhibitors - a revolutionary new class of lipid-lowering agents. Recent findings PCSK9 was discovered as a the third gene implicated in familial hypercholesterolemia. Population genetics studies, enabled by technological advances, were instrumental in validating PCSK9 as a therapeutic target. Monoclonal antibodies against PCSK9 were introduced in the clinic after an unprecedently rapid development path, in which clinical trial results confirmed that these drugs robustly lower cholesterol and improve clinical outcomes regardless of disease indication or background therapy. New strategies to PCSK9 inhibition are underway and have delivered promising preliminary results, including inhibition of PCSK9 synthesis by targeting the cellular gene expression machinery and vaccination. The future will tell whether directly targeting the genome through editing techniques will ultimately enable us to virtually eliminate many of the traditional CVD risk factors. Summary The extraordinary PCSK9 narrative highlights the opportunities offered by genetics-driven drug development and holds valuable lessons for future development programs

PCSK9 inhibitors: Novel therapeutic agents for the treatment of hypercholesterolemia

Reducing plasma levels of low-density lipoprotein cholesterol (LDL-c) remains the cornerstone in the primary and secondary prevention of cardiovascular disease. However, a substantial proportion of patients fail to achieve acceptable LDL-c levels with currently available lipid-lowering drugs. Over the last decade, inhibition of Proprotein Convertase Subtilisin/Kexin type 9 (PCSK9) has emerged as a promising target to reduce residual cardiovascular disease risk. Binding of PCSK9 to the LDL receptor targets the LDL receptor for lysosomal degradation. Inhibition of PCSK9 increases expression of the LDL receptor. This observation has led to the development of a number of approaches to directly target PCSK9. Three monoclonal antibodies against PCSK9 are currently being evaluated in phase 3 trials involving various patient categories on different background lipid lowering therapies. Current evidence shows reductions in LDL cholesterol levels of up to 70%, independent of background statin therapy. The results of phase 3 trials will demonstrate the long-term efficacy and safety of PCSK9 inhibition, and will indicate whether LDL-c lowering induced by this novel approach translates into beneficial effects on CVD outcom

Systemic wound care: a meta-review of cochrane systematic reviews

Wound care is a classic example of a surgical realm with a great variation in care. The diversity in wounds and wound treatments, the limited amount of convincing evidence, and the diverging opinions among doctors and nurses involved in wound care contribute to this undesirable variation in care. For chronic wounds, such as arterial or venous ulcers, pressure sores, and diabetic foot ulcers, but also for acute wounds after surgery or trauma, international and national guidelines provide recommendations on diagnostic procedures and treatment options, but rely mostly on expert opinion. We present the available evidence from Cochrane systematic reviews for the systemic treatment (i.e., not prevention) of patients with wounds, as opposed to topical wound treatments. This evidence shows: - Venous ulcers: High-compression therapy is the classic and evidence-based treatment for treating venous ulcers. Oral pentoxifylline promotes ulcer healing with and without compression therapy. Oral zinc is not effective to heal venous ulcers. - Acute wounds: Recombinant human growth hormone accelerates healing of large burn wounds and donor sites, while high-carbohydrate feeding might reduce the risk of pneumonia. Linezolid is more effective than vancomycin for treating skin and soft tissue infections. Hyperbaric oxygen may help heal crush wounds and skin grafts. Therapeutic touch does not heal acute wounds. - Pressure sores: Air-fluidized and some low-tech devices appear effective for treating existing pressure ulcers. Oral zinc, protein, or vitamin C supplements seem ineffective. Also, evidence is lacking on the effectiveness of repositioning regimes as a treatment option. - Diabetic ulcers: Hyperbaric oxygen therapy and pressure-relieving devices may improve healing rates. - Arterial ulcers: Prostanoids and spinal cord stimulation may be effective in healing ischemic ulcers. Thus, fortunately, some high-level evidence exists for various local and systemic interventions in wound care. Caregivers should be aware of, and apply, the strongest evidence available. Only when all stakeholders (patients, physicians, wound care nurses, but also manufacturers and buyers) implement this available evidence will optimum quality of care for patients with wounds be ensure

Inhibiting PCSK9 — biology beyond LDL control

Clinical trials have unequivocally shown that inhibition of proprotein convertase subtilisin/kexin type 9 (PCSK9) efficaciously and safely prevents cardiovascular events by lowering levels of LDL cholesterol. PCSK9 in the circulation is derived mainly from the liver, but the protein is also expressed in the pancreas, the kidney, the intestine and the central nervous system. Although PCSK9 modulates cholesterol metabolism by regulating LDL receptor expression in the liver, in vitro and in vivo studies have suggested that PCSK9 is involved in various other physiological processes. Although therapeutic PCSK9 inhibition could theoretically have undesired effects by interfering with these non-cholesterol-related processes, studies of individuals with genetically determined reduced PCSK9 function and clinical trials of PCSK9 inhibitors have not revealed clinically meaningful adverse consequences of almost completely eradicating PCSK9 from the circulation. The clinical implications of PCSK9 functions beyond lipid metabolism in terms of wanted or unwanted effects of therapeutic PCSK9 inhibition therefore appear to be limited. The objective of this Review is to describe the physiological role of PCSK9 beyond the LDL receptor to provide a rational basis for monitoring the effects of PCSK9 inhibition as these drugs gain traction in the clinic

Inclisiran for the treatment of cardiovascular disease: The ORION clinical development program

Inclisiran is a novel drug that inhibits PCSK9 synthesis specifically in the liver, harnessing the natural mechanism of RNAi. Phase I and II data show that inclisiran lowers low-density lipoprotein cholesterol levels on average by >50% with a duration of effect that enables twice-yearly dosing. Phases I, II and emerging Phase III data support inclisiran's safety, tolerability and risk-benefit profile. The ongoing ORION program includes Phase III trials that will provide robust evidence of inclisiran's safety and efficacy in individuals at high risk of atherosclerotic cardiovascular disease (ASCVD), including established ASCVD and familial hypercholesterolemia. In addition, the ORION-4 trial will assess the impact of inclisiran on cardiovascular outcomes in approximately 15,000 ASCVD subjects

New Drugs for Atherosclerosis

Atherosclerosis, the underlying process that ultimately leads to clinical cardiovascular disease (CVD), is caused by the multifactorial interaction of various conditions, and dyslipidemia is widely acknowledged as 1 of the crucial risk factors in this process. Statin drugs have been shown to decrease low-density lipoprotein cholesterol and CVD morbidity as well as mortality and are therefore pivotal in CVD prevention. Despite the use of statin drugs, CVD remains a leading cause of mortality worldwide, which suggests that additional lipid-lowering therapies are warranted. Several novel therapeutic agents, which are described in this review, are now well on their way in their respective development paths and might revolutionize anti-atherosclerotic drug therap

Moving Targets: Recent Advances in Lipid-Lowering Therapies

Statin therapy has delivered tremendous value to society by improving the burden of atherosclerotic cardiovascular disease. Nonetheless, atherosclerotic cardiovascular disease remains the leading cause of death globally. Technological advances such as in the field of genomics have revolutionized drug discovery and development and have revealed novel therapeutic targets to lower low-density lipoprotein cholesterol (LDL-C), as well as other detrimental lipids and lipoproteins. Therapeutic LDL-C lowering prevents atherosclerotic cardiovascular disease with an effect size proportional to absolute LDL-C reductions and time of exposure. This understanding supports the notion that reducing cumulative LDL-C exposure should be a key therapeutic target. PCSK9 (proprotein convertase subtilisin/kexin type 9) inhibiting monoclonal antibodies provides the possibility of reducing LDL-C to very low levels. Novel therapeutic platforms such as RNA inhibition present opportunities to combine robust lipid lowering with infrequent dosing regimens, introducing therapies with vaccine-like properties. The position of lipid-lowering therapies with targets other than LDL-C, such as Lp(a) [lipoprotein(a)], TRL (triglyceride-rich lipoproteins), and remnant cholesterol, will likely be determined by the results of ongoing clinical trials. Current evidence suggests that reducing Lp(a) or TRLs could attenuate atherosclerotic cardiovascular disease risk in specific categories of patients. This review provides an overview of the latest therapeutic developments, focusing on their mechanisms, efficacy, and safety