Multiple-dose pharmacokinetics, pharmacodynamics, and safety of atorvastatin, an inhibitor of HMG-CoA reductase, in healthy subjects

This study examined the pharmacokinetics, pharmacodynamics, and safety of atorvastatin, an investigational inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, in 50 healthy subjects by means of a randomized, double-blind parallel-group design. Volunteers received rising single and multiple doses of 0.5 to 80 mg/day atorvastatin (40 subjects) or placebo (10 subjects). The drug was administered once or twice daily for 14 days. Atorvastatin was well tolerated by healthy subjects. The most common adverse events reported after atorvastatin-headache and nausea-occurred as frequently after placebo. Atorvastatin peak concentration and area under the plasma concentration-time curve (AUC) values increased more than proportionally with atorvastatin dose after both single and multiple drug doses. The extent of atorvastatin absorption (AUC) was similar after once- or twice-daily drug administration. Steady-state drug concentrations were achieved by the third day of drug dosing. Mean elimination half-life values ranged from 11 to 24 hours. Atorvastatin accumulation was approximately 1.5- and 3.0-fold after once- and twice-daily administration, respectively. Atorvastatin produced dose-related reductions in total cholesterol and low-density lipoprotein cholesterol that were similar after once- and twice-daily drug administration. Reductions in mean total cholesterol and low-density lipoprotein cholesterol values ranged from 13% and 22% (2.5 mg/day) to 45% and 58% (80 mg/day), respectively (p < or = 0.0013 in comparison with placebo and with baseline over this dose range). In summary, atorvastatin doses of up to 80 mg/day were well tolerated and had significant cholesterol-lowering effects.

Effect of age and gender on pharmacokinetics of atorvastatin in humans

Atorvastatin is a new 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor that reduces plasma cholesterol by inhibiting cholesterol synthesis and increasing cellular uptake of low density lipoproteins. The effects of age and gender on the pharmacokinetics of atorvastatin after administration of single 20-mg tablets of atorvastatin were studied in 16 young and 16 elderly volunteers (8 men and 8 women in each age group). Plasma equivalent concentrations of atorvastatin were quantitated by a validated enzyme inhibition bioassay. Atorvastatin was well tolerated by the participants. The equivalent maximum concentration (Cmax) of atorvastatin was 42.5% higher in elderly participants (age, 66-92 years) than in young participants (age, 19-35 years) and 17.6% higher in women than in men. In addition, mean area under the concentration-time curve (AUC0-infinity) and half-life (t1/2) were 27.3% greater and 36.2% longer, respectively, in elderly adults than in young adults and 11.3% lower and 19.9% shorter, respectively, in women than in men. Because the primary site of action for HMG-CoA reductase inhibitors is the liver and atorvastatin is subject to extensive first-pass hepatic metabolism, it is unclear whether these age- and gender-related differences in the pharmacokinetics of atorvastatin will be clinically important. Results of subsequent safety and efficacy trials should help clarify the clinical significance of these pharmacokinetic differences.

Reduction of LDL cholesterol by 25% to 60% in patients with primary hypercholesterolemia by atorvastatin, a new HMG-CoA reductase inhibitor

This 6-week, double-blind clinical trial evaluated lipid parameter responses to different dosages of atorvastatin in patients with primary hypercholesterolemia. Atorvastatin is a new 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor under development. After completing an 8-week placebo-baseline dietary phase, 81 patients were randomly assigned to receive either placebo or 2.5, 5, 10, 20, 40, or 80 mg atorvastatin once daily for 6 weeks. Plasma LDL cholesterol reductions from baseline were dose related, with 25% to 61% reduction from the minimum dose to the maximum dose of 80 mg atorvastatin once a day. Plasma total cholesterol and apo B reductions were also dose related. Previously, reductions in LDL cholesterol of the magnitude observed in this study have been seen only with combination drug therapy. In this study, atorvastatin was well tolerated by hyperlipidemic patients, had an acceptable safety profile, and provided greater reduction in cholesterol than other previously reported HMG-CoA reductase inhibitors.

Efficacy and safety of pravastatin in patients with primary hypercholesterolemia. II. Once-daily versus twice-daily dosing

This 8-week multicenter, placebo-controlled trial compared the efficacy and safety of the HMG-CoA reductase inhibitor, pravastatin, when administered either as single doses of 40 mg in the morning (AM) or evening (PM) or 20 mg twice daily (bid) in 196 diet-stabilized outpatients with primary type II hypercholesterolemia. Mean reductions in total and low-density lipoprotein (LDL) cholesterol concentrations were observed in all pravastatin groups after 1 week and were sustained throughout the study (P less than or equal to 0.001 versus baseline and placebo). At week 8, mean reductions from baseline in the pravastatin treatment groups were 23-27% for total cholesterol and 30-34% for LDL cholesterol. LDL cholesterol was reduced greater than or equal to 15% by pravastatin in all patients in the group treated with 40 mg PM and in 88 and 96% in those receiving 20 mg bid and 40 mg AM, respectively. High density lipoprotein cholesterol was elevated (up to 8%) and triglycerides were reduced (up to 25%) by all pravastatin regimens (P less than or equal to 0.05). Pravastatin was well tolerated and was associated with a low incidence of adverse events. No patient withdrew from the study due to a pravastatin-related adverse event. Once-daily pravastatin is a safe and effective treatment for patients with primary hypercholesterolemia and has a favorable safety profile.

Efficacy and safety of pravastatin in patients with primary hypercholesterolemia. I. A dose-response study

This multicenter, double-blind, placebo-controlled, dose-response study was conducted in patients with primary hypercholesterolemia to examine the effects of pravastatin, a selective inhibitor of HMG-CoA reductase, on plasma lipids and lipoproteins. A total of 306 patients on cholesterol-lowering diets received twice daily doses of 5 mg, 10 mg, 20 mg pravastatin, or placebo for 12 weeks. Marked reductions in low density lipoprotein (LDL) cholesterol and total cholesterol were observed after 1 week of treatment; maximum lipid-lowering effects occurred at 4 weeks and were sustained for the duration of the trial. At week 12, pravastatin treatment resulted in dose-dependent mean reductions from baseline in LDL cholesterol of 17.5%, 22.9%, and 30.8% for the 3 doses tested (P less than or equal to 0001 compared with baseline and placebo). The reduction in LDL cholesterol was log-linear with respect to dose; each doubling of dose reduced LDL cholesterol an additional 6.5%. Dose-dependent reductions in total cholesterol from 12.9% to 23.3% also occurred (P less than or equal to 0.001). Triglycerides decreased by as 15.4% (P less than or equal to 0.001) and high-density lipoprotein (HDL) cholesterol increased approximately 7% (P less than or equal to 0.01), but these effects were not dose-dependent. No patient receiving pravastatin was discontinued during the 12-week trial. Transient episodes of rash and headache occurred. Slight increases in mean serum levels of ASAT and ALAT occurred, and 2% of both placebo- and pravastatin-treated patients reported myalgia although there was no clinically significant elevation of creatine kinase. These data indicate that pravastatin favorably affects all lipid parameters and is well tolerated.

The efficacy and safety of pravastatin, compared to and in combination with bile acid binding resins, in familial hypercholesterolaemia

Forty patients with familial hypercholesterolaemia (FH) were treated with 40 mg pravastatin once daily. Pravastatin decreased serum total and low density lipoprotein cholesterol (LDL) after 8 weeks of treatment by 28% and 33%, respectively, while high density lipoprotein cholesterol increased by 8% and triglycerides decreased by 14%. In 30 patients LDL cholesterol had not decreased below 5.0 mmol l-1 after 8 weeks of treatment, and in these patients resins were added to pravastatin, resulting in an additional decrease in total and LDL cholesterol of 8% and 12%, respectively. A control group of 22 FH patients was treated with placebo for 10 weeks, after which time resins were added, and they induced a decrease in total and LDL-cholesterol of 17% and 22%, respectively. Our results over a 24-week treatment period indicate that 40 mg pravastatin is more effective than 3 packets of resins in lowering LDL cholesterol, whereas the combination is most effective of all and can be used safely.

Treatment of familial hypercholesterolaemia: a controlled trial of the effects of pravastatin or cholestyramine therapy on lipoprotein and apolipoprotein levels

The efficacy and safety of a new, selective inhibitor of cholesterol synthesis, pravastatin, and the bile acid-binding resin, cholestyramine, were compared in a randomized, double-blind study of 120 patients with familial hypercholesterolaemia. After a run-in period of 8-10 weeks with assessment of dietary habits, the patients were treated with pravastatin + placebo, placebo + cholestyramine, or placebo alone. Active pravastatin therapy was initiated with 10 mg b.i.d. for 6 weeks, and was increased to 20 mg b.i.d. for the following 6 weeks. Cholestyramine was given at 24 g d-1, or the highest tolerable dose. After 6 weeks of therapy, serum total and LDL cholesterol levels were reduced by 17% and 21%, respectively, on pravastatin treatment, whereas the corresponding reductions with cholestyramine treatment were 24% and 30%, respectively. With an increased dose of pravastatin, serum and LDL cholesterol concentrations were reduced by 23% and 28%, respectively, after 12 weeks; the effect of cholestyramine was unchanged. HDL cholesterol levels increased in response to pravastatin, by 7% and 9% after 6 and 12 weeks, respectively. Concomitant changes in the concentrations of apolipoproteins B and AI were observed. Three patients discontinued the study because of side-effects: two subjects were treated with pravastatin and one was given placebo. The prevalence of side-effects (including laboratory abnormalities) was 35% for pravastatin, 30% for placebo, and 53% (significantly higher) for cholestyramine. We conclude that pravastatin, in a 40 mg daily dose, is as effective as cholestyramine in lowering LDL cholesterol in familial hypercholesterolaemia. Since the frequency of side-effects is higher with cholestyramine, pravastatin offers a promising alternative for the therapy of this genetic disease.

[Evaluation of the efficacy and safety of pravastatin in primary hypercholesterolemia]

Hypercholesterolemia can be a risk factor which engenders coronary heart disease. Today, it seems certain that lowering the cholesterolemia reduces this risk, especially if this reduction is referred to the cholesterol which is linked to the low density lipoprotein, called LDL. It has been demonstrated that the principle way to remove the LDL is by getting it into the hepatocyte through a specific membrane receptor, the research, therefore, has been developed with the aim of pharmacologically modifying the quota of intercellular cholesterol and consequently, in the modulation of the receptivity function by the interference of the LDL uptake, assisting a faster clearance. We can identify a new class of pharmacological drugs, that are the specific inhibitors of the HMGCoA reductase, fundamental enzime in the biosynthesis of cholesterol. This group of inhibitors has recently been enriched by the addition of a new molecule pravastatin. Our task has been to confirm the effectiveness and tolerability of pravastatin, administered for a prolonged period to patients with high levels of cholesterolemia; we have compared it with gemfibrozil, a well-known medicine which has hypocholesterolemic effects. In conclusion, our work, whilst emphasising the expediency of ipolipidic treatment, has undoubtedly proved, that 40 mg of pravastatin in a single evening dose, shows a high degree of efficiency, without side effects. Due to these factors, we can also say that pravastatin prevents, or really induces the regression, of atheroscherotic disease.

Dose-dependent hypolipidemic effect of an inhibitor of HMG-CoA reductase, pravastatin (CS-514), in hypercholesterolemic subjects. A double blind test

The hypolipidemic effect of a new HMG-CoA reductase inhibitor, pravastatin, was examined. The reductions of serum cholesterol and LDL-cholesterol were dose-dependent and significant differences were observed between placebo and 10 or 20 mg groups (P less than 0.01), and 10 and 20 mg (P less than 0.05) groups. The reduction rate of cholesterol after 8 weeks during medication was 16.1% in the 10 mg group, 20.5% in the 20 mg group compared to baseline serum cholesterol levels. LDL-cholesterol decreased by 23.9% in the 10 mg group, and 29.8% compared to baseline LDL-cholesterol in the 20 mg group. The lowering of total cholesterol was entirely attributed to a reduction in LDL-cholesterol.

The effect of CS-514 on serum lipids and apolipoproteins in hypercholesterolemic subjects

CS-514 is a metabolic product of compactin and has a potent cholesterol-lowering effect in vitro and in animal studies by inhibiting 3-hydroxy-3-methylglutaryl-coenzyme A reductase. The efficacy and adverse effects of the agent were studied in 41 hypercholesterolemic subjects by administering daily doses of 5, 20, or 40 mg for four weeks under double-blind conditions. Mean total serum cholesterol level was reduced by 11.1% in the 5-mg group, 18.8% in the 20-mg group, and 25.3% in the 40-mg group. Marked reduction of total serum cholesterol level was also observed in heterozygous familial hypercholesterolemics. Mean low-density lipoprotein cholesterol level and apolipoprotein B concentration decreased by 38.5% and 28.8%, respectively, in the 40-mg group, while high-density lipoprotein cholesterol level increased by 11.8%. No serious clinical and laboratory abnormalities were observed. Plasma cortisol and testosterone levels were not significantly affected. These results suggest that CS-514 will be a useful agent in the treatment of nonfamilial and heterozygous familial hypercholesterolemia.