Efficacy and safety of an extended-release formulation of fluvastatin for once-daily treatment of primary hypercholesterolemia

The LDL-Receptor and its Molecular Properties: From Theory to Novel Biochemical and Pharmacological Approaches in Reducing LDL-cholesterol

BACKGROUND

The Low-Density Lipoprotein (LDL) Receptor (LDL-R) is a transmembrane protein playing a crucial role in effective lipid homeostasis. Various therapeutic agents have been used in the management of dyslipidemias, however, the outcome of therapeutic target is debated.

OBJECTIVE

The aim of this review is to summarize and fully understand the current concept regarding LDL-R and its molecular properties, metabolic pathway, factors affecting LDL-R activity and all available pharmacological interventions. Additionally, non-lipid related properties of LDL-R are also referred.

METHODS

Literature from the PubMed database was extracted to identify papers between 1984 to 2017 regarding LDL-R and therapeutic agents on dyslipidemia management.

RESULTS

We analyzed basic data regarding agents associated with LDL-R (Sterol Regulating Element-Binding Proteins - SREBPs, Protein ARH, IDOL, Thyroid Hormones, Haematologic Disorders, Protein convertase subtilisin kexintype 9 - PCSK-9, ApoC-III) as well as non-lipid related properties of LDL-R, while all relevant (common and novel) pharmacological interventions (statins, fibrates, cholesterol absorption inhibitors, bile acid sequestrants and PCSK- 9) are also referred.

CONCLUSION

LDL-R and its molecular properties are involved in lipid homeostasis, so potentially sets the therapeutic goals in cardiovascular patients, which is usually debated. Further research is needed in order to fully understand its properties, as well as to find the potential pharmacological interventions that could be beneficial in cholesterol homeostasis and various morbidities in order to reach the most appropriate therapeutic goal.

Fluvastatin for lowering lipids

BACKGROUND

Fluvastatin is thought to be the least potent statin on the market, however, the dose-related magnitude of effect of fluvastatin on blood lipids is not known.

OBJECTIVES

Primary objectiveTo quantify the effects of various doses of fluvastatin on blood total cholesterol, low-density lipoprotein (LDL cholesterol), high-density lipoprotein (HDL cholesterol), and triglycerides in participants with and without evidence of cardiovascular disease.Secondary objectivesTo quantify the variability of the effect of various doses of fluvastatin.To quantify withdrawals due to adverse effects (WDAEs) in randomised placebo-controlled trials.

SEARCH METHODS

The Cochrane Hypertension Information Specialist searched the following databases for randomised controlled trials up to February 2017: the Cochrane Central Register of Controlled Trials (CENTRAL) (2017, Issue 1), MEDLINE (1946 to February Week 2 2017), MEDLINE In-Process, MEDLINE Epub Ahead of Print, Embase (1974 to February Week 2 2017), the World Health Organization International Clinical Trials Registry Platform, CDSR, DARE, Epistemonikos and ClinicalTrials.gov. We also contacted authors of relevant papers regarding further published and unpublished work. No language restrictions were applied.

SELECTION CRITERIA

Randomised placebo-controlled and uncontrolled before and after trials evaluating the dose response of different fixed doses of fluvastatin on blood lipids over a duration of three to 12 weeks in participants of any age with and without evidence of cardiovascular disease.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility criteria for studies to be included, and extracted data. We entered data from placebo-controlled and uncontrolled before and after trials into Review Manager 5 as continuous and generic inverse variance data, respectively. WDAEs information was collected from the placebo-controlled trials. We assessed all trials using the 'Risk of bias' tool under the categories of sequence generation, allocation concealment, blinding, incomplete outcome data, selective reporting, and other potential biases.

MAIN RESULTS

One-hundred and forty-five trials (36 placebo controlled and 109 before and after) evaluated the dose-related efficacy of fluvastatin in 18,846 participants. The participants were of any age with and without evidence of cardiovascular disease, and fluvastatin effects were studied within a treatment period of three to 12 weeks. Log dose-response data over doses of 2.5 mg to 80 mg revealed strong linear dose-related effects on blood total cholesterol and LDL cholesterol and a weak linear dose-related effect on blood triglycerides. There was no dose-related effect of fluvastatin on blood HDL cholesterol. Fluvastatin 10 mg/day to 80 mg/day reduced LDL cholesterol by 15% to 33%, total cholesterol by 11% to 25% and triglycerides by 3% to 17.5%. For every two-fold dose increase there was a 6.0% (95% CI 5.4 to 6.6) decrease in blood LDL cholesterol, a 4.2% (95% CI 3.7 to 4.8) decrease in blood total cholesterol and a 4.2% (95% CI 2.0 to 6.3) decrease in blood triglycerides. The quality of evidence for these effects was judged to be high. When compared to atorvastatin and rosuvastatin, fluvastatin was about 12-fold less potent than atorvastatin and 46-fold less potent than rosuvastatin at reducing LDL cholesterol. Very low quality of evidence showed no difference in WDAEs between fluvastatin and placebo in 16 of 36 of these short-term trials (risk ratio 1.52 (95% CI 0.94 to 2.45).

AUTHORS' CONCLUSIONS

Fluvastatin lowers blood total cholesterol, LDL cholesterol and triglyceride in a dose-dependent linear fashion. Based on the effect on LDL cholesterol, fluvastatin is 12-fold less potent than atorvastatin and 46-fold less potent than rosuvastatin. This review did not provide a good estimate of the incidence of harms associated with fluvastatin because of the short duration of the trials and the lack of reporting of adverse effects in 56% of the placebo-controlled trials.

Novel biodegradable polyester poly(propylene succinate): synthesis and application in the preparation of solid dispersions and nanoparticles of a water-soluble drug

Poly(propylene succinate) (PPSu) polymers of average molecular weights from 2,800 to 13,100 g/mol were synthesized and characterized with regard to crystallinity, thermal properties, and cytocompatibility. Higher molecular weight samples exhibited lower degree of crystallinity and melted at lower temperatures. Melting of the polymer appeared to begin at 38 degrees C. PPSu cytocompatibility was investigated based on human umbilical vein endothelial cells viability in the presence of increasing concentrations of polymer, and it was found that PPSu exhibited comparable cytocompatibility with poly(DL-lactide). The feasibility of applying PPSu as a drug carrier was shown for the first time, as solid dispersions and nanoparticles of sodium fluvastatin based in PPSu were prepared. Drug release rates decreased with increasing the molecular weight of PPSu in both solid dispersions and nanoparticles. For dispersions prepared from PPSu of the same molecular weight, drug release rates increased with drug loading. It appears that PPSu applicability as a drug carrier warrants further consideration.

The use of fluvastatin in cardiovascular risk management

BACKGROUND

Fluvastatin was the first synthetic 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor (statin) to be developed and is used in the management of dyslipidaemia in primary and secondary prevention of cardiovascular disease.

OBJECTIVE

This article reviews the properties of fluvastatin and experience accrued through its use in clinical practice and clinical trials.

METHODS

Relevant publications were identified through the PubMed database and product information held by the US Federal Drug Administration was also reviewed.

RESULTS/CONCLUSIONS

In the authors' opinion, fluvastatin exhibits a favourable safety profile in comparison to other statins, with a low incidence of adverse effects and a reduced propensity for interactions with other drugs. However, fluvastatin is a less potent cholesterol-lowering agent than newer statins on the market and its future predominant use is likely to be in niche patient groups at risk of side effects or drug interactions with other agents.

Overcoming ???Ageism??? Bias in the Treatment of Hypercholesterolaemia

Atherosclerosis is a progressive, lifelong condition that is the leading cause of death among middle-aged and elderly individuals aged > or =65 years. Up to 80% of elderly patients are found to have evidence of obstructive coronary heart disease at autopsy. Demographic trends, including the advancing median age and life expectancy of Western societies, suggest that a large share of the burden of atherosclerotic plaque is likely to be borne by elderly individuals. These trends are in part due to increases in a number of chronic diseases associated with adverse cardiovascular outcomes, including metabolic syndrome, diabetes mellitus and chronic kidney disease. Because the elderly have a higher attributable risk of coronary heart disease as a result of hypercholesterolaemia, more coronary deaths and overall events can be prevented via treatment in this age group compared with younger persons with hypercholesterolaemia. The efficacy, safety and tolerability of HMG-CoA reductase inhibitors (statins) have been confirmed in randomised, controlled, multicentre trials involving large numbers of patients aged > or =65 years. Although muscle symptoms such as myalgia are relatively common adverse events, more severe signs of myolysis such as myopathy and rhabdomyolysis are rare, but their risk is elevated by conditions (e.g. concomitant medications) that increase the systemic exposure of these agents. Statins differ in their susceptibility to increases in systemic exposure, but most statins have been demonstrated to be well tolerated and safe when administered to elderly patients. These favourable clinical findings should help clinicians counter highly prevalent 'ageism' bias in statin prescribing, whereby elderly patients, particularly those at highest cardiovascular risk, are often denied the benefits of statins without any meaningful foundation.

Short-term efficacy and safety of extended-release fluvastatin in a large cohort of elderly patients

The efficacy and safety of lipid-lowering agents in elderly individuals have not been extensively assessed. This population generally takes more drugs concurrently than middle-aged patients, and are therefore at higher risk of drug-drug interactions. This large-scale, randomized, double-blind, placebo-controlled study investigated the efficacy and safety of extended-release (XL) fluvastatin 80 mg once daily for up to 1 year in elderly patients with primary hypercholesterolemia. A total of 1229 patients (mean age, 75.5 years) were randomized. After 2 months of treatment, fluvastatin XL 80 mg significantly decreased plasma lipid levels from baseline compared with placebo; fluvastatin reduced total cholesterol by 25% compared with a decrease of 2.5% in the placebo group, low-density lipoprotein cholesterol was -33% vs. -2.5%, respectively, and triglycerides were -13.3% vs. 2.9%, respectively (p<0.00001). The safety profile of fluvastatin XL was similar to that of placebo. Fluvastatin XL 80 mg once daily was well tolerated and effectively managed plasma lipid profiles in a large cohort of elderly patients. These findings are consistent with data obtained previously in younger recipients of fluvastatin XL 80 mg, and reinforce the safety of fluvastatin in a population at high risk of drug-drug interactions.

Lovastatin extended release: a review of its use in the management of hypercholesterolaemia

Lovastatin extended release (ER) provides a new form of delivery for lovastatin, an HMG-CoA reductase inhibitor. Lovastatin ER delivers the drug in a more sustained fashion, as shown by a smoother plasma concentration-time profile, a lower maximum plasma concentration and a prolonged half-life compared with that of lovastatin immediate release (IR). At dosages of 10-60 mg/day, lovastatin ER significantly reduced levels of total cholesterol, low density lipoprotein (LDL)-cholesterol and triglycerides, and increased levels of high density lipoprotein-cholesterol, in patients with primary hypercholesterolaemia in a randomised, double-blind study of 12 weeks' duration. These effects were maintained in a 6-month extension study in which patients received lovastatin 40 or 60 mg/day. In a randomised 4-week study in 24 patients with primary hypercholesterolaemia, the reduction in plasma LDL-cholesterol levels was significantly greater with lovastatin ER 40 mg/day than with the IR formulation administered at the same dosage. Lovastatin ER was well tolerated in all studies and adverse events were usually mild to moderate and transient. The tolerability profile of lovastatin ER was similar to that of lovastatin IR. There were no reports of clinically relevant elevations in liver transaminases or creatine phosphokinase attributed to the drug in recipients of lovastatin ER.

CONCLUSION

The ER formulation of lovastatin provides smooth and sustained delivery of this established and well-tolerated agent over the dosage interval, significantly reducing LDL-cholesterol in patients with primary hypercholesterolaemia. If, as expected, the beneficial changes in lipid levels are maintained during long-term treatment and further clinical experience confirms the greater efficacy of the lovastatin ER formulation than the IR formulation, then lovastatin ER is likely to supplant lovastatin IR and provide a useful option in the management of patients with dyslipidaemia and prevention of coronary heart disease.

The effect of an HMG-CoA reductase inhibitor on arteriosclerotic nanoplaque formation and size in a biosensor model

Proteoheparan sulfate can be adsorbed to a methylated silica surface in a monomolecular layer via its transmembrane hydrophobic protein core domain. Due to electrostatic repulsion, its anionic glycosaminoglycan side chains are stretched out into the blood substitute solution, thereby representing a receptor site for specific lipoprotein binding through basic amino acid-rich residues within their apolipoproteins. The binding process was studied by ellipsometric techniques. Low-density lipoprotein (LDL) was found to deposit strongly at the proteoheparan sulfate-coated surface, particularly in the presence of Ca(2+), apparently through complex formation 'proteoglycan-LDL-calcium'. This ternary complex build-up may be interpreted as arteriosclerotic nanoplaque formation on the molecular level responsible for the arteriosclerotic primary lesion. HDL bound to heparan sulfate proteoglycan protected against LDL deposition and completely suppressed calcification of the proteoglycan-lipoprotein complex. In addition, HDL was able to decelerate the ternary complex deposition and to disrupt newly formed nanoplaques. Therefore, HDL attached to its proteoglycan receptor sites is thought to raise a multidomain barrier, selection and control motif for transmembrane and paracellular lipoprotein uptake into the arterial wall. The molecular arteriosclerosis model was tested on its reliability in a biosensor application in order to unveil possible acute pleiotropic effects of the lipid lowering drug fluvastatin. The very low-density lipoprotein (VLDL)/intermediate-density lipoprotein (IDL)/LDL and VLDL/IDL/LDL/HDL plasma fractions from a high-risk patient with dyslipoproteinemia and type 2 diabetes mellitus showed beginning arteriosclerotic nanoplaque formation already at a normal blood Ca(2+) concentration, with a strong increase at higher Ca(2+) concentrations. Nanoplaque formation and size of the HDL-containing lipid fraction remained well below that of the LDL-containing lipid fraction. Fluvastatin, whether applied acutely to the patient (one single 80 mg slow release matrix tablet) or in a 2-months medication regimen, markedly slowed down this process of ternary aggregational nanoplaque build-up and substantially inhibited nanoplaque size development at all Ca(2+) concentrations used. The acute action resulted without any significant change in lipid concentrations of the patient. Furthermore, after nanoplaque generation, fluvastatin, similar to HDL, was able to reduce nanoplaque formation and size. These immediate effects of fluvastatin have to be taken into consideration while interpreting the clinical outcome of long-term studies.

A model to assess the cost effectiveness of statins in achieving the UK National Service Framework target cholesterol levels

BACKGROUND

Coronary heart disease (CHD) is a public health priority in the UK. The National Service Framework (NSF) has set standards for the prevention, diagnosis and treatment of CHD, which include the use of cholesterol-lowering agents aimed at achieving targets of blood total cholesterol (TC) < 5.0 mmol/L and low density lipoprotein-cholesterol (LDL-C) < 3.0 mmol/L. In order to achieve these targets cost effectively, prescribers need to make an informed choice from the range of statins available.

AIM

To estimate the average and relative cost effectiveness of atorvastatin, fluvastatin, pravastatin and simvastatin in achieving the NSF LDL-C and TC targets.

DESIGN

Model-based economic evaluation.

METHODS

An economic model was constructed to estimate the number of patients achieving the NSF targets for LDL-C and TC at each dose of statin, and to calculate the average drug cost and incremental drug cost per patient achieving the target levels. The population baseline LDL-C and TC, and drug efficacy and drug costs were taken from previously published data. Estimates of the distribution of patients receiving each dose of statin were derived from the UK national DIN-LINK database.

RESULTS

The estimated annual drug cost per 1000 patients treated with atorvastatin was pound 289000, with simvastatin pound 315000, with pravastatin pound 333000 and with fluvastatin pound 167000. The percentages of patients achieving target are 74.4%, 46.4%, 28.4% and 13.2% for atorvastatin, simvastatin, pravastatin and fluvastatin, respectively. Incremental drug cost per extra patient treated to LDL-C and TC targets compared with fluvastatin were pound 198 and pound 226 for atorvastatin, pound 443 and pound 567 for simvastatin and pound 1089 and pound 2298 for pravastatin, using 2002 drug costs.

CONCLUSIONS

As a result of its superior efficacy, atorvastatin generates a favourable cost-effectiveness profile as measured by drug cost per patient treated to LDL-C and TC targets. For a given drug budget, more patients would achieve NSF LDL-C and TC targets with atorvastatin than with any of the other statins examined.

Fluvastatin

Fluvastatin was the first wholly synthetic statin to the market and is effective in reducing total and low density lipoprotein cholesterol, which translates into reductions in coronary heart disease events. The Lescol Intervention Prevention Study has established the effectiveness of the early use of statins in reducing recurrent events in high-risk patients with coronary heart disease post percutaneous coronary interventions. Fluvastatin is well-tolerated with few side effects. The occurrence of significant abnormalities in liver enzymes is infrequent, and the risk of myositis and rhabdomyolysis seems to be less than with other statins. There have been no reports of fatal rhabdomyolysis to date. The potential for drug interactions with fluvastatin is low. It seems safe in combination with cyclosporin and there have been few reports of rhabdomyolysis when using fluvastatin in combination with other lipid-lowering agents. It is nevertheless important to be vigilant for this potentially important side effect and, as with other statins, inform patients of the potential risk and suggestive symptoms. Fluvastatin provides a useful option in treating hypercholesterolaemia in patients at high risk of coronary heart disease.

Biosensing of arteriosclerotic nanoplaque formation and interaction with an HMG-CoA reductase inhibitor

Proteoheparan sulphate can be adsorbed to a methylated silica surface in a monomolecular layer via its transmembrane hydrophobic protein core domain. As a result of electrostatic repulsion, its anionic glycosaminoglycan side chains are stretched out into the blood substitute solution, thereby representing one receptor site for specific lipoprotein binding through basic amino acid-rich residues within their apolipoproteins. The binding process was studied by ellipsometric techniques suggesting that high-density lipoprotein (HDL) has a high binding affinity and a protective effect on interfacial heparan sulphate proteoglycan layers with respect to low-density lipoprotein (LDL) and Ca2+ complexation. Low-density lipoprotein was found to deposit strongly at the proteoheparan sulphate-coated surface, particularly in the presence of Ca2+, apparently through complex formation 'proteoglycan-LDL-calcium'. This ternary complex build-up may be interpreted as arteriosclerotic nanoplaque formation on the molecular level responsible for the arteriosclerotic primary lesion. On the other hand, HDL bound to heparan sulphate proteoglycan protected against LDL deposition and completely suppressed calcification of the proteoglycan-lipoprotein complex. In addition, HDL was able to decelerate the ternary complex deposition. Therefore, HDL attached to its proteoglycan receptor sites is thought to raise a multidomain barrier, selection and control motif for transmembrane and paracellular lipoprotein uptake into the arterial wall. Although much remains unclear regarding the mechanism of lipoprotein depositions at proteoglycan-coated surfaces, it seems clear that the use of such systems offers possibilities for investigating lipoprotein deposition at a 'nanoscopic' level under close to physiological conditions. In particular, Ca2+-promoted LDL deposition and the protective effect of HDL even at high Ca2+ and LDL concentrations agree well with previous clinical observations regarding risk and beneficial factors for early stages of atherosclerosis. Considering this, the system was tested on its reliability in a biosensor application in order to unveil possible acute pleiotropic effects of the lipid lowering drug fluvastatin. The very low-density lipoprotein (VLDL)/intermediate-density lipoprotein (IDL)/LDL plasma fraction from a high risk patient with dyslipoproteinaemia and type 2 diabetes mellitus showed beginning arteriosclerotic nanoplaque formation already at a normal blood Ca2+ concentration, with a strong increase at higher Ca2+ concentrations. Fluvastatin, whether applied to the patient (one single 80 mg slow release matrix tablet) or acutely in the experiment (2.2 micromol L-1), markedly slowed down this process of ternary aggregational nanoplaque complexation at all Ca2+ concentrations used. This action resulted without any significant change in lipid concentrations of the patient. Furthermore, after ternary complex build-up, fluvastatin, similar to HDL, was able to reduce nanoplaque adsorption and size. These immediate effects of fluvastatin have to be taken into consideration while interpreting the clinical outcome of long-term studies.

Safety, tolerability, and pharmacokinetics of an extended-release formulation of fluvastatin administered once daily to patients with primary hypercholesterolemia

Fluvastatin sodium (Lescol, Novartis Pharmaceutical Corp., East Hanover, NJ, U.S.A.), a potent 3-hydroxy-3-methylglutaryl coenzyme A (HMG Co-A) reductase inhibitor that limits cholesterol biosynthesis, is available as a 40-mg immediate-release formulation capsule. An extended-release formulation for once-daily administration has been developed for patients with primary hypercholesterolemia who may benefit from doses higher than 40 mg/day. This phase I study evaluated the safety, tolerability, and pharmacokinetics of a new fluvastatin extended-release formulation at doses ranging from 80-640 mg/day in 40 hypercholesterolemic patients. After a 2-week dietary stabilization phase, patients (Fredrickson type IIa/IIb), 18-55 years of age, were randomly assigned to four groups to receive oral fluvastatin extended-release (80, 160, 320, or 640 mg) or matching placebo once daily for 13 days. Fluvastatin extended-release was generally safe and well tolerated at doses of 80-320 mg/day. Within this dose range, linear pharmacokinetics was observed after single and multiple dosing. At 640 mg, fluvastatin extended-release was not well tolerated. Six of the seven actively treated patients at this dose experienced adverse events, including diarrhea, headache, and clinically relevant elevations in serum transaminase concentrations. In addition, nonlinear pharmacokinetics, possibly due to saturation of first-pass metabolism, was observed at this dose, causing higher than expected serum drug concentrations. Once-daily administration of fluvastatin extended-release at doses of 80-320 mg/day was generally safe and well tolerated in patients with primary hypercholesterolemia over a 13-day dosing period.