Once-daily pravastatin in patients with primary hypercholesterolemia: a dose-response study

Pravastatin for lowering lipids

BACKGROUND

A detailed summary and meta-analysis of the dose-related effect of pravastatin on lipids is not available.

OBJECTIVES

Primary objective To assess the pharmacology of pravastatin by characterizing the dose-related effect and variability of the effect of pravastatin on the surrogate marker: low-density lipoprotein (LDL cholesterol). The effect of pravastatin on morbidity and mortality is not the objective of this systematic review. Secondary objectives • To assess the dose-related effect and variability of effect of pravastatin on the following surrogate markers: total cholesterol; high-density lipoprotein (HDL cholesterol); and triglycerides. • To assess the effect of pravastatin on withdrawals due to adverse effects.

SEARCH METHODS

The Cochrane Hypertension Information Specialist searched the following databases for randomized controlled trials (RCTs) up to September 2021: CENTRAL (2021, Issue 8), Ovid MEDLINE, Ovid Embase, Bireme LILACS, the WHO International Clinical Trials Registry Platform, and ClinicalTrials.gov. We also contacted authors of relevant papers regarding further published and unpublished work. The searches had no language restrictions.

SELECTION CRITERIA

Randomized placebo-controlled trials evaluating the dose response of different fixed doses of pravastatin 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 lipid data from placebo-controlled trials into Review Manager 5 as continuous data and withdrawal due to adverse effects (WDAEs) data as dichotomous data. We searched for WDAEs information from all trials. We assessed all trials using Cochrane's risk of bias tool under the categories of sequence generation, allocation concealment, blinding, incomplete outcome data, selective reporting, and other potential biases.

MAIN RESULTS

Sixty-four RCTs evaluated the dose-related efficacy of pravastatin in 9771 participants. The participants were of any age, with and without evidence of cardiovascular disease, and pravastatin effects were studied within a treatment period of three to 12 weeks. Log dose-response data over the doses of 5 mg to 160 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 pravastatin on blood HDL cholesterol. Pravastatin 10 mg/day to 80 mg/day reduced LDL cholesterol by 21.7% to 31.9%, total cholesterol by 16.1% to 23.3%,and triglycerides by 5.8% to 20.0%. The certainty of evidence for these effects was judged to be moderate to high. For every two-fold dose increase there was a 3.4% (95% confidence interval (CI) 2.2 to 4.6) decrease in blood LDL cholesterol. This represented a dose-response slope that was less than the other studied statins: atorvastatin, rosuvastatin, fluvastatin, pitavastatin and cerivastatin. From other systematic reviews we conducted on statins for its effect to reduce LDL cholesterol, pravastatin is similar to fluvastatin, but has a decreased effect compared to atorvastatin, rosuvastatin, pitavastatin and cerivastatin. The effect of pravastatin compared to placebo on WADES has a risk ratio (RR) of 0.81 (95% CI 0.63 to 1.03). The certainty of evidence was judged to be very low.

AUTHORS' CONCLUSIONS

Pravastatin lowers blood total cholesterol, LDL cholesterol and triglyceride in a dose-dependent linear fashion. This review did not provide a good estimate of the incidence of harms associated with pravastatin because of the lack of reporting of adverse effects in 48.4% of the randomized placebo-controlled trials.

Effects of Different Types of Statins on Lipid Profile: A Perspective on Asians

CONTEXT

The present review aimed at reviewing the effects of different statins on lipid profile, particularly in Asians.

EVIDENCE ACQUISITION

PubMed searches were conducted using the keywords 'statin, effect, and lipid profile' from database inception through March 2016. In this review, 718 articles were retrieved from the primary search. After reviewing the titles, abstracts, and full texts, we found that 59 studies met our inclusion criteria. These also included subsequent reference searches of retrieved articles.

RESULTS

CURVES study compared the effect on lipid profile between atorvastatin and other statins. This study demonstrated that low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), and triglycerides (TG) were reduced more with atorvastatin compared to simvastatin, pravastatin, lovastatin, and fluvastatin. However, simvastatin provided a greater elevation of high-density lipoprotein cholesterol (HDL-C) compared to atorvastatin. The STELLAR trial was based on dose-to-dose comparisons between atorvastatin and rosuvastatin efficacy in reducing LDL-C. Te present study also revealed that as the doses of rosuvastatin, simvastatin, and pravastatin increased, HDL-C also increased, with rosuvastatin having the greatest effect. However, HDL-C levels decreased as the dose of atorvastatin increased. The DISCOVERY study involving the Asian population revealed that the percentage of patients achieving the European goals for LDL-C and TC at 12 weeks was higher in rosuvastatin group compared to atorvastatin group.

CONCLUSIONS

The effects of statins on lipid profile are dose dependent. Most studies showed that rosuvastatin has the best effect on lipid profile. Prescribing lower doses of statins in Asians seems necessary.

Statins for the primary prevention of cardiovascular disease

BACKGROUND

Reducing high blood cholesterol, a risk factor for cardiovascular disease (CVD) events in people with and without a past history of CVD is an important goal of pharmacotherapy. Statins are the first-choice agents. Previous reviews of the effects of statins have highlighted their benefits in people with CVD. The case for primary prevention was uncertain when the last version of this review was published (2011) and in light of new data an update of this review is required.

OBJECTIVES

To assess the effects, both harms and benefits, of statins in people with no history of CVD.

SEARCH METHODS

To avoid duplication of effort, we checked reference lists of previous systematic reviews. The searches conducted in 2007 were updated in January 2012. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (2022, Issue 4), MEDLINE OVID (1950 to December Week 4 2011) and EMBASE OVID (1980 to 2012 Week 1).There were no language restrictions.

SELECTION CRITERIA

We included randomised controlled trials of statins versus placebo or usual care control with minimum treatment duration of one year and follow-up of six months, in adults with no restrictions on total, low density lipoprotein (LDL) or high density lipoprotein (HDL) cholesterol levels, and where 10% or less had a history of CVD.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies for inclusion and extracted data. Outcomes included all-cause mortality, fatal and non-fatal CHD, CVD and stroke events, combined endpoints (fatal and non-fatal CHD, CVD and stroke events), revascularisation, change in total and LDL cholesterol concentrations, adverse events, quality of life and costs. Odds ratios (OR) and risk ratios (RR) were calculated for dichotomous data, and for continuous data, pooled mean differences (MD) (with 95% confidence intervals (CI)) were calculated. We contacted trial authors to obtain missing data.

MAIN RESULTS

The latest search found four new trials and updated follow-up data on three trials included in the original review. Eighteen randomised control trials (19 trial arms; 56,934 participants) were included. Fourteen trials recruited patients with specific conditions (raised lipids, diabetes, hypertension, microalbuminuria). All-cause mortality was reduced by statins (OR 0.86, 95% CI 0.79 to 0.94); as was combined fatal and non-fatal CVD RR 0.75 (95% CI 0.70 to 0.81), combined fatal and non-fatal CHD events RR 0.73 (95% CI 0.67 to 0.80) and combined fatal and non-fatal stroke (RR 0.78, 95% CI 0.68 to 0.89). Reduction of revascularisation rates (RR 0.62, 95% CI 0.54 to 0.72) was also seen. Total cholesterol and LDL cholesterol were reduced in all trials but there was evidence of heterogeneity of effects. There was no evidence of any serious harm caused by statin prescription. Evidence available to date showed that primary prevention with statins is likely to be cost-effective and may improve patient quality of life. Recent findings from the Cholesterol Treatment Trialists study using individual patient data meta-analysis indicate that these benefits are similar in people at lower (< 1% per year) risk of a major cardiovascular event.

AUTHORS' CONCLUSIONS

Reductions in all-cause mortality, major vascular events and revascularisations were found with no excess of adverse events among people without evidence of CVD treated with statins.

Clinical consequences following regulatory changes in respect to reimbursement of statins cost by the Icelandic Social Insurance Administration

INTRODUCTION

On 1 March 2009, a new reimbursement system was introduced by the Ministry of Health of Iceland regarding drugs to treat hyperlipidaemia. The Social Insurance Administration was only authorised to reimburse 10 and 20 mg simvastatin unless patients were eligible to receive a medical card from the Social Insurance Administration. The purpose of this study was to evaluate the influence of this reimbursement regulation on the clinical outcome.

MATERIALS AND METHODS

Patients that received hyperlipidaemia treatment and were admitted to the cardiac ward were enrolled. The criteria were that the patients had been admitted 1 year prior to the regulation change and were using other statins than simvastatin.

RESULTS

Out of 233 eligible patients 170 (73%) reached the treatment goal before the switch. After the switch, only 126 (54%) reached their goal (p<0.05). Total cholesterol was found to be increased after the switch by a mean of 0.48 mmol/l (range 3.90-5.53 mmol/l, p<0.001). Low-density lipoprotein cholesterol increased by a mean of 0.48 mmol/l (range 1.62-3.11, p<0.001). The level of triglycerides did not change significantly. Before the introduction of the new regulations, 73% of subjects were well controlled, but after 1 March 2009, this figure dropped to 46% (37% decrease).

CONCLUSIONS

In order to lower costs for subsidising drugs, a switch to simvastatin from other cholesterol-lowering drugs was implemented (by the Ministry of Health of Iceland). The result was a significant and unwanted increase in cholesterol levels among patients with heart disease. The reason seems to be inaccurate prescriptions due to lack of competence among physicians and pharmacists. The use of "one drug fits all" does not comply here.

Statins for the primary prevention of cardiovascular disease

BACKGROUND

Reducing high blood cholesterol, a risk factor for cardiovascular disease (CVD) events in people with and without a past history of coronary heart disease (CHD) is an important goal of pharmacotherapy. Statins are the first-choice agents. Previous reviews of the effects of statins have highlighted their benefits in people with coronary artery disease. The case for primary prevention, however, is less clear.

OBJECTIVES

To assess the effects, both harms and benefits, of statins in people with no history of CVD.

SEARCH STRATEGY

To avoid duplication of effort, we checked reference lists of previous systematic reviews. We searched the Cochrane Central Register of Controlled Trials (Issue 1, 2007), MEDLINE (2001 to March 2007) and EMBASE (2003 to March 2007). There were no language restrictions.

SELECTION CRITERIA

Randomised controlled trials of statins with minimum duration of one year and follow-up of six months, in adults with no restrictions on their total low density lipoprotein (LDL) or high density lipoprotein (HDL) cholesterol levels, and where 10% or less had a history of CVD, were included.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies for inclusion and extracted data. Outcomes included all cause mortality, fatal and non-fatal CHD, CVD and stroke events, combined endpoints (fatal and non-fatal CHD, CVD and stroke events), change in blood total cholesterol concentration, revascularisation, adverse events, quality of life and costs. Relative risk (RR) was calculated for dichotomous data, and for continuous data pooled weighted mean differences (with 95% confidence intervals) were calculated.

MAIN RESULTS

Fourteen randomised control trials (16 trial arms; 34,272 participants) were included. Eleven trials recruited patients with specific conditions (raised lipids, diabetes, hypertension, microalbuminuria). All-cause mortality was reduced by statins (RR 0.83, 95% CI 0.73 to 0.95) as was combined fatal and non-fatal CVD endpoints (RR 0.70, 95% CI 0.61 to 0.79). Benefits were also seen in the reduction of revascularisation rates (RR 0.66, 95% CI 0.53 to 0.83). Total cholesterol and LDL cholesterol were reduced in all trials but there was evidence of heterogeneity of effects. There was no clear evidence of any significant harm caused by statin prescription or of effects on patient quality of life.

AUTHORS' CONCLUSIONS

Although reductions in all-cause mortality, composite endpoints and revascularisations were found with no excess of adverse events, there was evidence of selective reporting of outcomes, failure to report adverse events and inclusion of people with cardiovascular disease. Only limited evidence showed that primary prevention with statins may be cost effective and improve patient quality of life. Caution should be taken in prescribing statins for primary prevention among people at low cardiovascular risk.

Genetic polymorphisms of uptake (OATP1B1, 1B3) and efflux (MRP2, BCRP) transporters: implications for inter-individual differences in the pharmacokinetics and pharmacodynamics of statins and other clinically relevant drugs

Recent pharmacogenomic/pharmacogenetic studies have disclosed important roles of drug transporters in the pharmacokinetic/pharmacodynamic (PK/PD) profiles of some clinically relevant drugs. It has concurrently been explained that variations in the drug transporter genes are associated with not only inter-individual but also inter-ethnic differences in PK/PD profiles of these drugs. This review focuses on two uptake and two efflux transporters. Organic anion transporting polypeptide (OATP) 1B1 and OATP1B3 are uptake transporters, specifically expressed in the liver, and considered important for drugs, particularly as their pharmacological target organ is the liver. Two ATP-binding cassette transporters, multi-drug resistance-associated protein 2 and breast cancer resistance protein, are efflux transporters, expressed in various human tissues, and considered particularly important for intestinal drug absorption and hepatic drug elimination. All 3-hydroxyl-3-methylglutaryl-CoA reductase inhibitors (statins) except fluvastatin are substrates for OATP1B1, but hepatobiliary (canalicular) efflux transporters differ among statins. In this review, we update the pharmacogenomic/pharmacogenetic properties of these transporters and their effects on PK/PD profiles of statins and other clinically relevant drugs. In addition, we describe a physiologically-based pharmacokinetic model for predicting the effects of changes in transporter activities on systemic and hepatic exposure to pravastatin.

A Translational Medicine perspective of the development of torcetrapib: Does the failure of torcetrapib development cast a shadow on future development of lipid modifying agents, HDL elevation strategies or CETP as a viable molecular target for atherosclerosis? A case study of the use of biomarkers and Translational Medicine in atherosclerosis drug discovery and development

Although the relationship between HDL (high density lipoprotein) function and cardiovascular (CV) risk has been extensively explored, the premise that HDL elevation is linked to reduced CV risks and that high HDL cholesterol (HDL-C) might be a potential surrogate biomarker for reduced CV risk remains controversial. Substantial genetic, molecular, biochemical and preclinical evidence have raised the hope that HDL-C elevation via CETP inhibition might generate clinical benefits. However, four large-scale clinical trials with the CETP inhibitor torcetrapib failed to demonstrate benefits on CV clinical outcomes. Likewise, biomarkers that were supposed to predict vascular risk reduction provided disappointing results. The sad tale of torcetrapib development emphasizes the need for a paradigm shift from the conventional drug development mode to a biomarker-based Translational Medicine (TMed) strategy. Emergence of further CETP inhibitors encourage continued development of such compounds for cardiovascular risk management. However, there is a need to adopt biomarker-driven TMed strategies in target validation, target-compound interaction, pharmacodynamic activities, disease modification and patient selection to guide future drug development efforts. This commentary analyzes the issues surrounding the demise of torcetrapib and proposes a TMed-based road map towards successful development of new CETP inhibitors.

Metabolic syndrome abating the beneficial effect of pravastatin treatment on adhesion of endothelium by monocytes in subjects with hypercholesterolemia

Statin, a potent lipid-lowering agent, ameliorates the interaction of monocytes and endothelium, a critical step in the atherosclerotic process. However, it remains unclear whether this effect of statin depends on different doses or the presence of metabolic syndrome. In this prospectively double-blind study, 21 hypercholesterolemia subjects, with low-density lipoprotein cholesterol between 130 and 170 mg/dL, received low-dose (10 mg/d) or high-dose (40 mg/d) pravastatin treatment for 8 weeks. We assessed the reduction of monocyte adhesion to cultured endothelium between different-dose groups and the relationship to metabolic syndrome. Total cholesterol and low-density lipoprotein cholesterol were significantly decreased after 40-mg pravastatin treatment (-23.3% +/- 3.7%, P < .001 and -28.8% +/- 3.0%, P < .001), and the reductions were greater than those in the 10-mg group (P = .041 and P = .045, respectively). There was no significant difference in monocyte adhesion between high-dose and low-dose pravastatin treatment. When all subjects were divided into an improvement group and a no improvement group, according to the median of change percentage of monocyte adhesion after pravastatin treatment, there were significantly more subjects with metabolic syndrome in the no improvement than the improvement group (6 vs 1 person, P =.024). Using logistic regression analysis, metabolic syndrome, rather than dose effect of pravastatin, was an independent predictor of interaction between monocytes and endothelium (95% confidence interval = 0.001-0.865, P = .041). Attenuating adhesion between monocytes and endothelium is altered by the presence of metabolic syndrome when hypercholesterolemia subjects receive pravastatin treatment.

Blockade of adaptive defensive changes in cholesterol uptake and synthesis in AML by the addition of pravastatin to idarubicin + high-dose Ara-C: a phase 1 study

Following exposure to cytotoxic agents, acute myeloid leukemia (AML) blasts elevate cellular cholesterol in a defensive adaptation that increases chemoresistance, but blockade of HMG-CoA reductase with statins restores chemosensitivity in vitro. This phase 1 study evaluated adding pravastatin (PV) (40-1680 mg/day, days 1-8) to idarubicin (Ida) ([12 mg/ (M2 x day), days 4-6]) + high-dose cytarabine (Ara-C; HDAC) [1.5 g/(M2 x day) by CI, days 4-7] in 15 newly diagnosed and 22 salvage patients with unfavorable (n = 26) or intermediate (n = 10) prognosis cytogenetics. Compared with historical experience with Ida-HDAC, the duration of neutropenia and throbmbocytopenia and the toxicity profile were unaffected by the addition of PV. During PV loading (day 0-4) serum triglyceride and total and LDL cholesterol levels decreased in nearly all patients. Pharmacokinetic studies demonstrated higher and more sustained serum PV levels with PV doses above 1280 mg/day. CR/CRp was obtained in 11 of 15 new patients, including 8 of 10 with unfavorable cytogenetics, and 9 of 22 salvage patients. An MTD for PV + Ida-HDAC was not reached. Addition of PV to Ida-HDAC was safe, and the encouraging response rates support conducting further trials evaluating the effect of cholesterol modulation on response in AML.

SLCO1B1 521T-->C functional genetic polymorphism and lipid-lowering efficacy of multiple-dose pravastatin in Chinese coronary heart disease patients

AIMS

Pravastatin is a 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, which is widely used both in primary and secondary prevention of coronary heart disease (CHD). Pravastatin is not subject to metabolism by cytochrome P450s, but it is actively transported from blood into target tissues (e.g. hepatocytes in the liver) by the organic anion transporting polypeptide 1B1 (OATP1B1), encoded by SLCO1B1. The aim of the present study was to evaluate the impact of SLCO1B1 521T-->C (Val174Ala) functional genetic polymorphism on the lipid-lowering efficacy of multiple-dose pravastatin in Chinese patients with CHD.

METHODS

Forty-five hospitalized patients with CHD prospectively received pravastatin as a single-agent therapy (20 mg day(-1) p.o.) for 30 days. Serum triglycerides, total cholesterol, low-density lipoprotein-cholesterol and high-density lipoprotein-cholesterol concentrations were determined before and after pravastatin treatment.

RESULTS

Pravastatin treatment significantly decreased plasma lipids in all patients (P < 0.001). Importantly, we showed an attenuated pravastatin pharmacodynamic effect on total cholesterol in patients with 521TC heterozygote genotype (from 5.52 +/- 0.51 mmol l(-1) to 4.70 +/- 0.35 mmol l(-1), % change -14.5 +/- 6.6%, N = 9) compared with 521TT homozygote genotype (from 5.47 +/- 1.15 mmol l(-1) to 4.21 +/- 0.89 mmol l(-1), % change -22.4 +/- 10.3%, N = 36) (mean +/- SD, P = 0.03, two-tailed test with alpha set at 5%). SLCO1B1 521T-->C functional polymorphism did not significantly influence pravastatin pharmacodynamics on other plasma lipids (P > 0.05).

CONCLUSIONS

The 521T-->C polymorphism of SLCO1B1 appears to modulate significantly the total cholesterol-lowering efficacy of pravastatin in Chinese patients with CHD. Further studies are warranted to determine the extent to which SLCO1B1 genetic variation may contribute to resistance to pravastatin in Asian patients treated with standard doses of pravastatin.

Pharmacokinetics and response to pravastatin in paediatric patients with familial hypercholesterolaemia and in paediatric cardiac transplant recipients in relation to polymorphisms of the SLCO1B1 and ABCB1 genes

AIMS

Our aim was to investigate associations between the single nucleotide polymorphisms (SNPs) in the SLCO1B1 (encoding OATP1B1) and ABCB1 (encoding P-glycoprotein) genes with the pharmacokinetics and efficacy of pravastatin in children with heterozygous familial hypercholesterolaemia (HeFH) and in paediatric cardiac transplant recipients.

METHODS

Twenty children with HeFH (aged 4.9-15.6 years) and 12 cardiac transplant recipients (aged 4.4-18.7 years and receiving triple immunosuppressive medication) who had participated in previous pharmacokinetic and pharmacodynamic studies with pravastatin were genotyped for the -11187G > A and 521T > C SNPs in the SLCO1B1 gene and for the 2677G > T/A and 3435C > T SNPs in the ABCB1 gene.

RESULTS

Two HeFH patients with the -11187GA genotype had a 81% lower peak plasma pravastatin concentration (Cmax) (difference in means -13.9 ng ml(-1), 95% CI -21.1, -6.7; P < 0.001) and a 74% smaller area under the plasma concentration-time curve (AUC0, infinity) (-25.3 ng ml(-1) h, 95% CI -35.6, -15.0; P < 0.0001) and significantly greater increase in high density lipoprotein (HDL) cholesterol after 2 months treatment with pravastatin than patients with the reference genotype. No significant differences were seen in the pharmacokinetics or effects of pravastatin between HeFH patients with the SLCO1B1 521TC and 521TT genotypes. The cardiac transplant recipients with the SLCO1B1 521TC genotype (n = 3) had a 46% lower Cmax (-67.7 ng ml(-1), 95% CI -135.7, 0.3; P = 0.055) and 62% lower AUC(0,24 h) (-228.5 ng ml(-1) h, 95% CI -402.7, -54.3; P = 0.016) and a shorter half-life (t1/2) (0.9 +/- 0.1 vs. 1.3 +/- 0.4 h, P = 0.015) of pravastatin than those with the reference genotype. Decreases in total and low-density lipoprotein cholesterol by pravastatin were significantly smaller, and the increase in HDL-cholesterol was greater in the transplant recipients with the 521TC genotype compared with patients with the 521TT reference genotype.

CONCLUSIONS

In children with HeFH and in paediatric cardiac transplant recipients receiving immunosuppressive medication, the -11187G > A and SLCO1B1 521T > C SNPs were associated with decreased plasma concentrations of pravastatin. These differences are opposite to those seen previously in healthy adults. The mechanisms underlying these phenomena are unclear and warrant further study.

Systematic review and meta-analysis of clinically relevant adverse events from HMG CoA reductase inhibitor trials worldwide from 1982 to present

PURPOSE

Our objective was to determine the association of clinically relevant adverse events from a systematic review and meta-analysis of statin randomized controlled trials (RCT).

METHODS

We performed the meta-analysis in the manner of a Cochrane Collaboration systematic review. Outcomes were discontinuances of therapy or muscle-related symptoms due to adverse events. We searched for articles from 1982 through June 2006 in MEDLINE and other databases. The main inclusion criteria were double blind, placebo controlled RCTs with a monotherapy intervention of any marketed statin and active surveillance of adverse events. We excluded studies of drug interactions, organ transplants, or exercise, or those not meeting all of the study quality criteria. The primary analysis was a statin formulation stratified fixed-effect model using Peto odds-ratios (POR). Secondary analyses explored the stability of the primary results.

RESULTS

Over 86,000 study participants from 119 studies were included. Available statins were associated with a lower POR of discontinuance (overall: 0.88 [0.84, 0.93], largest effect with pravastatin: 0.79 [0.74, 0.84]), an elevated POR of rhabdomyolysis (1.59 [0.54, 4.70]) and myositis (2.56 [1.12, 5.85]), and null odds of myalgia (1.09 [0.97, 1.23]). Cerivastatin by comparison demonstrated larger PORs for discontinuances and muscle-related adverse events. Secondary analyses demonstrated the stability of the results.

CONCLUSIONS

Overall, discontinuation of statin therapy due to adverse events was no worse than placebo. The risks of muscle-related adverse events were in general agreement with the known risks of statins.

Influence of Drug Transporter Polymorphisms on Pravastatin Pharmacokinetics in Humans

The role of drug transporters in pravastatin disposition is underlined by the fact that pravastatin does not undergo significant cytochrome P-450 (CYP)-mediated biotransformation. The organic anion transporting polypeptide 1B1 (OATP1B1), encoded by SLCO1B1, and multidrug resistance-associated protein 2 [MRP2 (ABCC2)], are thought to be the major transporters involved in the pharmacokinetics of pravastatin in humans. Other transporters that may play a role include OATP2B1, organic anion transporter 3 (OAT3), bile salt export pump (BSEP), and the breast cancer resistance protein (BCRP). OATP1B1 and MRP2 mediate the hepatic uptake and biliary excretion of pravastatin, respectively. The SLCO1B1 and ABCC2 polymorphisms probably contribute to the high interindividual variability in pravastatin disposition. Recent small studies have characterized the impact of the SLCO1B1 polymorphism on pravastatin in humans, and especially the c.521T>C single-nucleotide polymorphism (SNP) seems to be an important determinant of pravastatin pharmacokinetics. Pravastatin plasma concentrations may be up to 100% higher in subjects carrying the c.521C variant, as found in the *5, *15, *16, and *17 haplotypes, reflecting diminished OATP1B1-mediated uptake into the major site of pravastatin elimination, the liver. The SLCO1B1 polymorphism seems to have a similar impact on the pharmacokinetics of single- and multiple-dose pravastatin. Overall, 2-5% of individuals in various populations may be expected to show markedly elevated plasma pravastatin concentrations due to the SLCO1B1 polymorphism. Of note, the impact of the SLCO1B1 polymorphism on statins may be dependent on ethnicity. Although individuals with a diminished hepatic uptake of pravastatin might be expected to show reduced cholesterol-lowering efficacy due to lower intracellular pravastatin concentrations, there is preliminary evidence to suggest that the SLCO1B1 polymorphism is not a major determinant of non-response to pravastatin. The possible consequences of drug transporter polymorphisms, especially the SLCO1B1 and ABCC2 polymorphisms, for the lipid-lowering efficacy and tolerability of pravastatin in various ethnic groups warrant further study.

Hydrophilic statin suppresses vein graft intimal hyperplasia via endothelial cell-tropic Rho-kinase inhibition

BACKGROUND

Recent studies suggest that statins can protect the vasculature in a manner that is independent of their lipid-lowering activity through inhibition of the small guanosine triphosphate-binding protein, Rho, and Rho-associated kinase. Little information is available on the inhibitory effect of statins on vein graft intimal hyperplasia, the main cause of late graft failure after bypass grafting. We therefore examined the effects of a hydrophilic statin on vein graft intimal hyperplasia in vivo and Rho-kinase activity in vitro.

METHODS

In the first experiment, rabbits were randomized to a control group (n = 7) that was fed regular rabbit chow or to a pravastatin group (n = 7) that was fed regular rabbit chow supplemented with 10 mg/kg pravastatin sodium. The branches of the jugular vein were ligated and an approximately 3-cm segment of the jugular vein was taken for an autologous reversed-vein graft. The carotid artery was cut and replaced with the harvested autologous jugular vein. At 2 and 4 weeks after the operation, vein grafts in both groups were harvested, and intimal hyperplasia of the vein grafts was assessed. In the second experiment, human umbilical vein endothelial cells and vascular smooth muscle cells were cultured and then treated with 1 micromol/L and 30 micromol/L pravastatin for 24 hours and harvested. Immunoblotting was performed on the resulting precipitates. Quantitative evaluation of phosphorylated myosin binding subunit and endothelial nitric oxide synthase was performed by densitometric analysis.

RESULTS

We demonstrated that oral administration of the hydrophilic statin pravastatin to normocholesterolemic rabbits inhibited intimal hyperplasia of carotid interposition-reversed jugular vein grafts 4 weeks after implantation (pravastatin group, 39.5 +/- 3.5 microm vs control group, 64.0 +/- 7.1 microm; n = 7; P < .05) and suppressed cell proliferation and apoptosis in the neointima 2 weeks after implantation. In addition, we found that pravastatin inhibited Rho-kinase activity and accelerated endothelial nitric oxide synthase expression in human umbilical vein endothelial cells but did not inhibit Rho-kinase activity in vascular smooth muscle cells.

CONCLUSIONS

These novel findings clearly demonstrate that a hydrophilic statin can suppress intimal hyperplasia of the vein graft in vivo and also show endothelial cell-tropic inhibition of Rho-kinase in vitro. Furthermore, these results strongly support the clinical use of hydrophilic statins to prevent intimal hyperplasia of the vein graft after bypass grafting.

CLINICAL RELEVANCE

Late graft failure caused by neointimal hyperplasia limits the efficacy of vein grafting. Various treatments were examined to reduce neointimal hyperplasia, but a standard clinical treatment has not yet been established. We report here the inhibitory effect of pravastatin on the development of vein graft intimal hyperplasia. In addition, we demonstrate that pravastatin showed endothelial cell-tropic benefits through both the inhibition of Rho-kinase activity and acceleration of eNOS expression in vitro. Because the clinical benefits and safety of pravastatin have been established to a certain extent through long-term clinical usage, pravastatin may soon become standard treatment after vein bypass grafting.

Randomized comparison of the efficacy and safety of cerivastatin and pravastatin in 1,030 hypercholesterolemic patients. The Cerivastatin Study Group

OBJECTIVE

To determine the relative efficacy and safety of cerivastatin and pravastatin in patients with type II hypercholesterolemia.

PATIENTS AND METHODS

In this prospective, double-blind, parallel-group study, hypercholesterolemic patients were randomized to treatment with cerivastatin, 0.3 mg (n=250) or 0.4 mg (n=258), or pravastatin, 20 mg (n=266) or 40 mg (n=256), for 8 weeks.

RESULTS

Cerivastatin, 0.3 mg, was significantly more effective than pravastatin, 20 mg, in reducing low-density lipoprotein (LDL) cholesterol from baseline (-29.6% vs -26.8%; P=.008). Cerivastatin, 0.4 mg, was significantly more effective than pravastatin, 40 mg, in reducing LDL cholesterol (-34.2% vs -30.3%; P<.001). A larger proportion of cerivastatin-treated patients had greater than 40% reductions in LDL cholesterol than those receiving pravastatin (11.1% vs 6.0%). The percentage of patients who achieved the National Cholesterol Education Program (NCEP) target was 71.3% with cerivastatin, 0.3 mg, compared with 67.5% with pravastatin, 20 mg, and 74.0% with cerivastatin, 0.4 mg, compared with 71.1% with pravastatin, 40 mg (no significant difference). Cerivastatin, 0.3 mg, reduced total cholesterol to a greater extent than did pravastatin, 20 mg (P<.03). Both agents reduced triglycerides and increased high-density lipoprotein cholesterol to a similar degree (no significant differences). Cerivastatin and pravastatin were well tolerated.

CONCLUSIONS

Cerivastatin, 0.3 mg and 0.4 mg, showed greater efficacy than pravastatin, 20 mg and 40 mg, respectively, in lowering LDL cholesterol. Cerivastatin is safe and effective for patients with hypercholesterolemia who require aggressive LDL cholesterol lowering to achieve NCEP-recommended targets.

Ways to minimize adverse drug reactions. Individualized doses and common sense are key

The great majority of adverse drug reactions are dose-related and occur in patients taking standard doses of medications. These facts suggest that for many patients, standard drug doses may be excessive. The principle of variability among individuals, which requires tailoring the dose to the patient, needs to be reasserted in clinical medicine to reduce the incidence of side effects. Physicians should obtain patients' histories of drug reactions and have at hand information on the full range of effective drug doses, including data on low doses gathered in prerelease and postrelease drug studies. Whenever possible, manufacturers should provide a range of doses and breakable tablets to facilitate flexible dosing.

Comparative efficacy and tolerability of low-dose pravastatin versus lovastatin in patients with hypercholesterolemia

BACKGROUND

The HMG CoA reductase inhibitors have quickly become the most widely prescribed family of agents for the treatment of patients with elevated low-density lipoprotein (LDL) cholesterol. The incidence of side effects with these agents increases as the dose increases within the recommended dosage range. A lower dosage presumably would have a lower incidence of adverse effects. In addition, lower doses should translate into reduced drug costs.

METHODS AND RESULTS

We compared the efficacy of 10 mg of pravastatin and 10 mg of lovastatin in a randomized, crossover design trial among 30 patients with hypercholesterolemia. At baseline, their total cholesterol and LDL cholesterol levels were 249.0 +/- 27.3 and 185.1 +/- 25.5 mg/dL. After 4 weeks of treatment with lovastatin, the total cholesterol and LDL cholesterol levels fell to 202.8 +/- 29.6 and 141.0 +/- 25.3 mg/dL, decreases of 19% and 24%, respectively. Four weeks of pravastatin treatment resulted in levels of 212.6 +/- 30.8 and 150.5 +/- 25.5 mg/dL, or 15% and 19%, respectively.

CONCLUSIONS

There were highly significant changes in total cholesterol and LDL cholesterol levels with each agent and no differences in effect between the 2 agents. In 13 (43%) of the 30 patients, LDL levels were reduced to </=130 mg/dL with one of the agents. Both agents were generally well tolerated, with no clinically important change in liver function tests or creatinine kinase levels.

The antiatherogenic role of high-density lipoprotein cholesterol

Landmark clinical studies in the past 5 years that demonstrated diminished mortality and first coronary events following lowering of low-density lipoprotein (LDL) cholesterol stimulated considerable interest in the medical community. Yet, high-density lipoprotein (HDL) cholesterol, which transports circulating cholesterol to the liver for clearance, clearly also exerts antiatherogenic effects. The Framingham Heart Study produced compelling epidemiologic evidence indicating that a low level of HDL cholesterol was an independent predictor of coronary artery disease (CAD). Emerging experimental and clinical findings are, collectively, now furnishing a solid scientific foundation for this relation. First, the reverse cholesterol transport pathway--including the roles of nascent (pre-beta) HDL, apolipoprotein A-I, lecithin-cholesterol acyltransferase (LCAT), cholesteryl ester transport protein, and hepatic uptake of cholesteryl ester from HDL by liver--is better understood. For example, the identification of a hepatic HDL receptor, SR-BI, suggests a mechanism of delivery of cholesteryl ester to liver that differs from the receptor-mediated uptake of LDL. Second, apolipoprotein A-I, the major protein component of HDL, and 2 enzymes on HDL, paraoxonase and platelet-activating factor acetylhydrolase appear to diminish the formation of the highly atherogenic oxidized LDL. Third, lower levels of HDL cholesterol are associated in a dose-response fashion with the severity and number of angiographically documented atherosclerotic coronary arteries. Fourth, low HDL cholesterol predicts total mortality in patients with CAD and desirable total cholesterol levels (<200 mg/dL). Fifth, low HDL cholesterol concentrations appear to be associated with increased rates of restenosis after percutaneous transluminal coronary angioplasty. In terms of elevating HDL cholesterol, cessation of cigarette smoking, reduction to ideal body weight, and regular aerobic exercise all appear important. Most medications used to treat dyslipidemias will raise HDL cholesterol levels modestly; however, niacin appears to have the greatest potential to do so, and can increase HDL cholesterol up to 30%. Recognizing these data, the most recent report of the National Cholesterol Education Program identified low HDL cholesterol as a CAD risk factor and recommended that all healthy adults be screened for both total cholesterol and HDL cholesterol levels.

Comparative dose efficacy study of atorvastatin versus simvastatin, pravastatin, lovastatin, and fluvastatin in patients with hypercholesterolemia (the CURVES study)

The objective of this multicenter, randomized, open-label, parallel-group, 8-week study was to evaluate the comparative dose efficacy of the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor atorvastatin 10, 20, 40, and 80 mg compared with simvastatin 10, 20, and 40 mg, pravastatin 10, 20, and 40 mg, lovastatin 20, 40, and 80 mg, and fluvastatin 20 and 40 mg. Investigators enrolled 534 hypercholesterolemic patients (low-density lipoprotein [LDL] cholesterol > or = 160 mg/dl [4.2 mmol/L] and triglycerides < or = 400 mg/dl [4.5 mmol/L]). The efficacy end points were mean percent change in plasma LDL cholesterol (primary), total cholesterol, triglycerides, and high-density lipoprotein cholesterol concentrations from baseline to the end of treatment (week 8). Atorvastatin 10, 20, and 40 mg produced greater (p < or = 0.01) reductions in LDL cholesterol, -38%, -46%, and -51%, respectively, than the milligram equivalent doses of simvastatin, pravastatin, lovastatin, and fluvastatin. Atorvastatin 10 mg produced LDL cholesterol reductions comparable to or greater than (p < or = 0.02) simvastatin 10, 20, and 40 mg, pravastatin 10, 20, and 40 mg, lovastatin 20 and 40 mg, and fluvastatin 20 and 40 mg. Atorvastatin 10, 20, and 40 mg produced greater (p < or = 0.01) reductions in total cholesterol than the milligram equivalent doses of simvastatin, pravastatin, lovastatin, and fluvastatin. All reductase inhibitors studied had similar tolerability. There were no incidences of persistent elevations in serum transaminases or myositis.

Cerivastatin, a New Potent Synthetic HMG Co-A Reductase Inhibitor: Effect of 0.2 mg Daily in Subjects With Primary Hypercholesterolemia

BACKGROUND: Reduction of serum cholesterol, most notably low-density lipoprotein cholesterol is associated with reductions in cardiovascular morbidity and mortality. Statins have been shown to effectively reduce low-density lipoprotein cholesterol via inhibition of the hydroxymethyl-coenzyme A (HMG-CoA) reductase. Cerivastatin is the most potent HMG-CoA reductase inhibitor currently under study in the United States. METHODS AND RESULTS: A parallel group, randomized, placebo-controlled, double-blind, multicenter study was conducted to compare the efficacy and safety of three different dosing regimens of 0.2 mg/day of cerivastatin, a new HMG-CoA reductase inhibitor, in patients with hypercholesterolemia. After a 10-week diet-placebo lead-in period, 319 patients with low-density lipoprotein cholesterol >160 mg/dL were randomized to 4 weeks of treatment with one of the following regimens: cervastatin 0.1 mg twice daily, cerivastatin 0.2 mg once daily with the evening meal, cerivastatin 0.2 mg once daily at bedtime or placebo. All three active treatment groups produced statistically significant (P <.05) changes compared to aseline and placebo in total cholesterol (0.1 mg twice daily \_18.9%; 0.2 mg once daily with the evening meal: \_21.9%; 0.2 mg once daily at bedtime: \_22.1%; placebo: 0.0%), low-density lipoprotein cholesterol (0.1 mg twice daily: \_25.7%; 0.2 mg once daily with the evening meal: \_29.4%; 0.2 mg once daily at bedtime: \_30.4%; placebo: 1.4%) and high-density lipoprotein cholesterol (0.1 mg twice daily: 5.3%; 0.2 mg once daily with the evening meal: baseline and placebo, were also reduced by all active treatments (0.1 mg twice daily: \_11.6% [P =.05]; 0.2 mg once daily with the evening meal: \_11.6% [P =.05]; and 0.2 mg at bedtime: \_10.9% [P =.07]). The percentage change in total cholesterol and low-density lipoprotein cholesterol after 4 weeks of therapy for the once-daily cerivastatin groups was statistically significantly greater (P <.05) than the cerivastatin twice daily regimen. A treatment responser was seen by 1 week of therapy and was maximal by 3 weeks. The drug was well tolerated in all three dosing regimens and resulted in no significant increase in biochemical or clinical side effects compared to placebo. CONCLUSION: Cerivastatin is a novel, highly potent, well-tolerated HMG-CoA reductase inhibitor that produces low-density lipoprotein cholesterol reductions of approximately 30% when administered at 0.2 mg once a day in the evenings.

Effectiveness and safety of low-dose pravastatin and squalene, alone and in combination, in elderly patients with hypercholesterolemia

A double-blind, placebo-controlled study was conducted to compare the efficacy and safety of low-dose (10 mg) prevastatin and squalene (860 mg), either alone or in combination therapy, with placebo in the treatment of elderly patients with hypercholesterolemia. Ambulatory elderly patients (N = 102) were assigned in randomized fashion to receive active treatment or placebo for 20 weeks after a single-blind placebo lead-in period of 8 weeks. Total cholesterol and triglyceride levels in plasma were at least 250 mg/dL and less than 300 mg/dL, respectively. Concentrations of lipids and lipoproteins were measured, and clinical laboratory tests included liver function and creatine kinase determinations. Pravastatin 10 mg daily was more effective than squalene in reducing total cholesterol, low-density lipoprotein (LDL) cholesterol, and triglycerides and in increasing levels of high-density lipoprotein (HDL) cholesterol. Combination therapy significantly reduced total cholesterol and LDL cholesterol and increased HDL cholesterol to a greater extent than either drug alone. Adverse events and clinical laboratory abnormalities were generally mild and transient in all groups, and all but two patients finished the study. The incidence of side effects was low; myopathy did not occur. Coadministration of pravastatin and squalene combined the specific effects of the two drugs on lipoprotein concentrations. This combination may be useful and more cost-effective in elderly patients with hypercholesterolemia, who might have a higher incidence of side effects when using larger doses of pravastatin alone.

Prevention of coronary heart disease with pravastatin in men with hypercholesterolemia. West of Scotland Coronary Prevention Study Group

BACKGROUND

Lowering the blood cholesterol level may reduce the risk of coronary heart disease. This double-blind study was designed to determine whether the administration of pravastatin to men with hypercholesterolemia and no history of myocardial infarction reduced the combined incidence of nonfatal myocardial infarction and death from coronary heart disease.

METHODS

We randomly assigned 6595 men, 45 to 64 years of age, with a mean (+/- SD) plasma cholesterol level of 272 +/- 23 mg per deciliter (7.0 +/- 0.6 mmol per liter) to receive pravastatin (40 mg each evening) or placebo. The average follow-up period was 4.9 years. Medical records, electrocardiographic recordings, and the national death registry were used to determine the clinical end points.

RESULTS

Pravastatin lowered plasma cholesterol levels by 20 percent and low-density-lipoprotein cholesterol levels by 26 percent, whereas there was no change with placebo. There were 248 definite coronary events (specified as nonfatal myocardial infarction or death from coronary heart disease) in the placebo group, and 174 in the pravastatin group (relative reduction in risk with pravastatin, 31 percent; 95 percent confidence interval, 17 to 43 percent; P < 0.001). There were similar reductions in the risk of definite nonfatal myocardial infarctions (31 percent reduction, P < 0.001), death from coronary heart disease (definite cases alone: 28 percent reduction, P = 0.13; definite plus suspected cases: 33 percent reduction, P = 0.042), and death from all cardiovascular causes (32 percent reduction, P = 0.033). There was no excess of deaths from noncardiovascular causes in the pravastatin group. We observed a 22 percent reduction in the risk of death from any cause in the pravastatin group (95 percent confidence interval, 0 to 40 percent; P = 0.051).

CONCLUSIONS

Treatment with pravastatin significantly reduced the incidence of myocardial infarction and death from cardiovascular causes without adversely affecting the risk of death from noncardiovascular causes in men with moderate hypercholesterolemia and no history of myocardial infarction.

Efficacy and safety of pravastatin in the treatment of patients with type I or type II diabetes mellitus and hypercholesterolemia

PURPOSE

Patients with type I and type II diabetes mellitus have an increased risk of coronary heart disease. In many diabetics, hypercholesterolemia is present and further exacerbates this risk. We investigated the efficacy and safety of pravastatin in the treatment of patients with type I or type II diabetes mellitus and hypercholesterolemia.

PATIENTS AND METHODS

In this 24-week, multi-center, double-blind, placebo-controlled study, 94 patients (45 men, 49 women), 18 to 70 years of age, with type I or type II diabetes mellitus and hypercholesterolemia (fasting plasma low-density lipoprotein cholesterol [LDL-C] levels > 150 mg/dL and above the 75th percentile for the US population by age and gender) were randomized to receive pravastatin 20 mg hs or matching placebo. Two patients were randomized to treatment with drug for every 1 randomized to placebo. The dose could be doubled after 10 weeks, and cholestyramine or colestipol could be added after 18 weeks, as needed, to attempt to lower the LDL-C levels to below the 50th percentile for the US population.

RESULTS

Significant reductions in LDL-C (-27.6%), total cholesterol (-22.1%), very-low-density lipoprotein cholesterol (-22.6%), and triglycerides (-12.8%) (P < or = 0.001 versus placebo for all reductions), and significant increases in high-density lipoprotein cholesterol (4.4%) (P < or = 0.05 versus placebo) were noted in the pravastatin treatment group (average dose 29.5 mg) at 16 weeks. The beneficial lipid-lowering effects of pravastatin were maintained throughout the 24 weeks of the study. Pravastatin was well tolerated, and the frequency of side effects was similar in the pravastatin and placebo groups. No clinically significant changes in the control of diabetes, as assessed by fasting blood glucose levels and glycosylated hemoglobin measurements, were seen during this study.

CONCLUSION

The results of this study demonstrate that pravastatin is well tolerated and effective in lowering total cholesterol and LDL-C in patients with type I or type II diabetes mellitus and hypercholesterolemia.

Effects of pravastatin, a hydroxymethylglutaryl-CoA reductase inhibitor, on two human tumour cell lines

Competitive inhibitors of 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) reductase are currently used to treat patients with hypercholesterolaemia. These inhibitors affect not only cholesterol biosynthesis, but also the production of non-steroidal mevalonate derivatives, that are involved in a number of growth-regulatory processes. As a consequence, their potential use as anticancer drugs has been suggested. In order to examine long-term effects of this potential therapeutic approach, we cultivated the gastric carcinoma cell line, EPG85-257, and the breast tumour cell line, MDA-MB231, in the presence of increasing concentrations of the HMG-CoA reductase inhibitor, pravastatin. For both cell lines, this procedure led to the selection of resistant variants able to proliferate in more than 1000 microM inhibitor. By competitive reverse transcriptase/polymerase chain reaction assay (cRT-PCR), the expression of the mRNA for two key proteins of cellular cholesterol metabolism, HMG-CoA reductase and low-density lipoprotein (LDL) receptor, were analysed in sensitive and resistant cells. Despite similar growth rates, MDA-MB231 cells expressed approximately four times more HMG-CoA reductase mRNA than EPG85-257 cells and over 30 times more LDL receptor mRNA. Both mRNA species were coordinately regulated in the parental and in the pravastatin-resistant variant cells. Expression was highly stimulated (3- to 4-fold for the HMG-CoA reductase and 2- to 3-fold for the LDL receptor) in the resistant variants when cultured in lipoprotein-deficient medium in the presence of 1000 microM pravastatin. Immunocytological analysis of the expression of the HMG-CoA reductase and LDL receptor protein were in accordance with the data on specific mRNA expression obtained by cRT-PCR. Southern blot analysis revealed a 1.5-fold amplification of the HMG-CoA reductase gene in resistant MDA-MB231 cells, but not in the resistant EPG85-257 variant. Our data provide evidence for resistance mechanisms to pravastatin that are independent of the amplification of the HMG-CoA reductase gene. By analogy to the cell-culture models employed in this study, it is conceivable that similar mechanisms might occur in human tumour cells in vivo during long-term treatment with HMG-CoA reductase inhibitors. This might limit their application as chemotherapeutic anticancer agents.

A multinational study of the effects of low-dose pravastatin in patients with non-insulin-dependent diabetes mellitus and hypercholesterolemia. Pravastatin Multinational Study Group for Diabetes

This multinational, 16-week, randomized, double-blind, placebo-controlled study evaluated the efficacy and safety of low-dose pravastatin in 325 patients with non-insulin-dependent diabetes mellitus (NIDDM) and hypercholesterolemia [serum total cholesterol concentrations of 5.2-7.8 mmol/l (200 to 300 mg/dl)]. Patients were randomized to receive pravastatin 10 mg or matching placebo with doubling of the dose after 8 weeks if predefined target levels for total cholesterol [(i.e., < 5.2 mmol/l (200 mg/dl) or > 15% decrease from baseline] had not been achieved. At Week 16, pravastatin-treated patients showed a 21.4% decrease in serum low-density lipoprotein cholesterol (LDL-C) and a 13.5% reduction in serum total cholesterol (TC) concentrations (p < 0.001 compared with placebo). Levels of triglycerides (TG) were reduced 9.6% during pravastatin treatment (p < 0.05 compared with placebo) while high-density lipoprotein cholesterol (HDL-C) levels were increased 4.4% (p = NS). Adverse events and laboratory test abnormalities were similar among patients treated with pravastatin or placebo. Glycosylated hemoglobin (HbA1C) levels remained unchanged. The results of this study demonstrate that low-dose pravastatin is effective and well tolerated for lowering elevated cholesterol concentrations during short-term treatment of patients with NIDDM and hypercholesterolemia.

Efficacy and safety of pravastatin in the long-term treatment of elderly patients with hypercholesterolemia

PURPOSE

Elevated cholesterol levels are a major risk factor for coronary heart disease, which remains a significant problem in patients beyond age 65 years. Because drug therapy for the control of hypercholesterolemia in elderly patients is frequently considered to be indicated, we investigated the efficacy and safety of pravastatin in the treatment of elderly subjects with primary hypercholesterolemia.

PATIENTS AND METHODS

In this 96-week, multicenter, double-blind, placebo-controlled study, 142 subjects (95 women, 47 men) 64 to 90 years of age with elevated cholesterol levels despite dietary intervention were randomized to receive pravastatin 20 mg at bedtime or matching placebo (2:1). Dosage could be doubled after 8 weeks, a bile acid-binding resin could be added after 16 weeks, and nicotinic acid or probucol could be added after 32 weeks, as needed, to adequately lower the low-density lipoprotein cholesterol (LDL-C) levels.

RESULTS

Significant reductions in the levels of LDL-C (-30.9%), total cholesterol (Total-C; -21.9%), and triglycerides (TG; -16.7%) and significant increases in the levels of high-density lipoprotein cholesterol (HDL-C; 11.3%) were noted in the group receiving pravastatin treatment at 16 weeks (P < or = 0.001 compared with baseline, P < or = 0.01 compared with placebo). The cholesterol-lowering effects of pravastatin were sustained throughout the 96 weeks of the trial. Pravastatin was well tolerated, with an overall incidence of adverse events nearly identical to that of placebo.

CONCLUSIONS

In this study, pravastatin was well tolerated and effective in lowering LDL-C, Total-C, and TG and in raising HDL-C during long-term treatment of elderly patients with primary hypercholesterolemia.

Effects of pravastatin in patients with serum total cholesterol levels from 5.2 to 7.8 mmol/liter (200 to 300 mg/dl) plus two additional atherosclerotic risk factors. The Pravastatin Multinational Study Group for Cardiac Risk Patients

This placebo-controlled, multinational study evaluated the use of pravastatin in 1,062 patients with hypercholesterolemia (serum total cholesterol concentrations of 5.2 to 7.8 mmol/liter [200 to 300 mg/dl]) and > or = 2 additional risk factors for atherosclerotic coronary artery disease. Efficacy and safety analyses were performed on the initial 26-week, randomized, double-blind, placebo-controlled period; further safety analyses were conducted on the subsequent 52 weeks, which included an additional 26-week double-blind phase permitting other lipid-lowering agents and a final 26-week open-label period. At offweeks, pravastatin at a dose of 20 mg once daily at bedtime significantly lowered serum low-density lipoprotein cholesterol 26% (4.7 to 3.5 mmol/liter [182 to 135 mg/dl]), total cholesterol 19% (6.8 to 5.6 mmol/liter [263 to 217 mg/dl]) and triglycerides 12% (1.8 to 1.6 mmol/liter [159 to 142 mg/dl]) (p < 0.001 compared with placebo) and significantly raised serum high-density lipoprotein cholesterol 7% (1.1 to 1.2 mmol/liter [43 to 46 mg/dl]) (p < 0.001 compared with placebo). Efficacy of pravastatin was maintained at 26 weeks, and during this initial period there were significantly more serious cardiovascular adverse events in the placebo group (13 events, 2.4%) than in the pravastatin group (1 event, 0.2%) (p < 0.001). Six myocardial infarctions, 5 cases of unstable angina and 1 sudden cardiac death occurred in the placebo group, compared with none of these events in the pravastatin group. In this study, pravastatin produced beneficial effects on serum lipids and was associated with a reduction in the incidence of serious cardiovascular adverse events.

Pravastatin experience in elderly and non-elderly patients

Epidemiologic evidence linking elevated cholesterol concentrations and coronary heart disease (CHD) through the eighth decade of life provides a rationale for lowering cholesterol concentrations to reduce morbidity and mortality from CHD. Pravastatin, a well tolerated HMG CoA reductase inhibitor with a convenient once-daily dosing regimen, has been shown to effectively lower total and low density lipoprotein (LDL) cholesterol. Individual data from more than 1800 hypercholesterolemic patients enrolled in six double-blind, randomized, multicenter studies were pooled and then analyzed to compare the safety and efficacy of pravastatin in the elderly (i.e., patients at least 65 years old) and the non-elderly. In short-term studies (8-16 weeks), response was dose-related and similar in elderly and non-elderly subjects. Pravastatin 20 or 40 mg daily lowered total cholesterol 19-25%, LDL-cholesterol 25-33%, and triglycerides 14-23%; high density lipoprotein (HDL) cholesterol increased 5-10%. During long-term studies, improvements were sustained for more than 24 months in both the non-elderly and elderly. The incidences of adverse drug events and laboratory abnormalities were similar in the elderly and non-elderly patients in all groups (active treatment control with resin, pravastatin alone, or combination therapy). In short-term studies, treatment was discontinued because of adverse events in < 1% of all patients treated with pravastatin (all doses) or placebo. The frequency and profile of adverse events were similar among patients treated with pravastatin or placebo. In long-term studies, treatment was discontinued in 0.4% of patients in the pravastatin group and in 0.3% of the patients in the bile-acid-binding resin group. If drug therapy is warranted, pravastatin appears to be safe and effective for long-term use in elderly patients with hypercholesterolemia.

Pravastatin, lipids, and atherosclerosis in the carotid arteries: design features of a clinical trial with carotid atherosclerosis outcome

The Pravastatin, Lipids, and Atherosclerosis in the Carotids trial (PLAC-II) was initiated in 1987 and is the first double-masked randomized clinical trial with progression of early extracranial carotid atherosclerosis as an outcome variable. The trial will compare a lipid-lowering agent (pravastatin, a hydroxymethylglutaryl CoA reductase inhibitor) with placebo for ability to retard the rate of progression of extracranial carotid atherosclerosis over 3 years. Inclusion criteria consisted of prevalent coronary artery disease, moderately elevated low-density lipoprotein (LDL) cholesterol (between the 60th and 90th percentiles), and the presence of at least one extracranial carotid artery atherosclerotic plaque that had an intimal-medial thickness (IMT) > or = 1.3 mm as visualized by B-mode ultrasound. Of approximately 650 patients who qualified on the basis of coronary disease and elevated LDL cholesterol, 55% were excluded because of B-mode criteria. One hundred and fifty-one males and females 50-75 years of age were recruited. Random allocation produced placebo-treated and test-treated groups that were similar for baseline historical data, physical findings, laboratory tests, lipid values, and B-mode characteristics. Baseline concentrations of plasma total cholesterol, LDL cholesterol, and high-density lipoprotein (HDL) cholesterol were 234, 166, and 41 mg/dl, respectively. Baseline plasma concentration of triglyceride was 170 mg/dl. Despite selection of participants whose arteries, overall, were suitable for the trial, individual segments in some participants could not be visualized. Ninety-seven percent of the individual carotid artery segments were visualized in the common carotid, 88% in the bifurcation, and 63% in the internal carotid artery. Far walls were slightly more often visualized than near walls, and nonvisualization was most common for the near wall of the internal carotid. Nonvisualized segments were comparable between both treatment groups. The distribution of arterial walls with qualifying plaque of > or = 1.3 mm IMT was similar for the two groups, and the two groups were also comparable for the primary outcome determinant, mean maximum IMT (mean of maximum of all visualizable sites, 1.32 mm for each treatment group). There are special problems related to recruitment and evaluation of patients for a clinical trial such as this, but the atherosclerosis outcome measurement markedly enhances power and compensates for difficulty in recruitment.

Efficacy and tolerability of simvastatin and pravastatin in patients with primary hypercholesterolemia (multicountry comparative study). The European Study Group

A total of 291 patients with primary hypercholesterolemia [total plasma cholesterol > or = 6.20 mmol/liter (> or = 240 mg/dl)] were enrolled in an open, randomized, parallel, comparative study of simvstatin and pravastatin. All patients started or continued a standard lipid-lowering diet for > or = 6 weeks before entry into the 4-week placebo baseline period. There were 145 patients who received simvastatin and 146 patients who received pravastatin, both at the commonly recommended starting dose of 10 mg once daily, for a treatment period of 6 weeks. Concentrations of total cholesterol in plasma were reduced by 23% with simvastatin, and by 16% with pravastatin. Concentrations of low-density lipoprotein cholesterol in plasma were reduced by 32 and 22%, and high-density lipoprotein cholesterol concentrations were increased by 7 and 5% with simvastatin and pravastatin, respectively. Plasma triglyceride concentrations were reduced by 13% with simvastatin and by 6% with pravastatin. Adverse experiences were similar between treatment groups and both drugs were well tolerated. In each treatment group, 3 patients were withdrawn from the study for clinical adverse experiences; 1 patient in the pravastatin group required a reduction in dose to 5 mg/day because of insomnia. At the commonly recommended starting dose for each, simvastatin had a significantly greater lipid-lowering effect than pravastatin. Both drugs were well tolerated.

A clinical overview of dyslipidemias: treatment strategies

The strong epidemiologic relationship between specific lipoprotein levels (such as elevated low-density lipoprotein cholesterol or decreased high-density lipoprotein cholesterol) and the future development of coronary heart disease has been well documented. Within the past several years, landmark clinical trials have clearly demonstrated that the incidence of coronary heart disease events is reduced when lipoprotein abnormalities are corrected via pharmacologic therapy. These findings have prompted clinicians to become more vigilant with regard to recognition of dyslipidemias and institution of treatment. This review focuses on the more common primary and secondary dyslipidemias and the currently available lipid-lowering therapies for each disorder. Results of recent coronary angiographic trials are discussed, and implications for the medical management of established coronary heart disease are assessed.