BACKGROUND AND AIM:Clinical data suggesting that larger decreases in low density lipoprotein cholesterol (LDL-C) result in greater reductions in coronary heart disease events have led to the establishment of aggressive LDL-C targets for the treatment of hypercholesterolemia. In view of this, the efficacy and safety of a new maximum dose of simvastatin, 80 mg, were evaluated in 9 studies involving 2819 hypercholesterolemic patients. This report focuses on the combined results from the 4 main or Pivotal studies in which a total of 1936 patients received simvastatin 40 or 80 mg for 36 to 48 weeks. METHODS AND RESULTS:The Pivotal studies had similar randomized, multicenter, controlled, double-blind, parallel-group designs. Their combined results demonstrated a significant advantage in the LDL-C-lowering effect for the 80 mg dose. At week 24, the mean percentage reductions (95% confidence intervals) from baseline in LDL-C for the 40 and 80 mg groups were -39.8% (-40.9, -38.7) and -45.7% (-46.5, -45.0) respectively (p < 0.001, between groups), and larger reductions in total cholesterol and triglycerides were also observed in the 80 mg group. Both doses were well tolerated. No new or unexpected adverse events were observed and the overall clinical event profiles were similar in the two groups. Clinically significant hepatic transaminase increases (> 3 times the upper limit of normal/ULN) and myopathy (muscle symptoms plus creatine kinase increase > 10 times ULN) occurred infrequently with both doses. Simvastatin 80 mg had a comparable efficacy and safety profile in women and men as well as in non-elderly and elderly patients. CONCLUSIONS:Simvastatin 80 mg provides additional LDL-C and triglyceride reductions compared to the 40 mg dose and has an excellent safety and tolerability profile.

In view of the role of both the de novo biosynthesis and receptor-mediated uptake of cholesterol for normal steroidogenesis, we evaluated whether extending the therapeutic dose of the hepatic hydroxymethyl glutaryl coenzyme A (HMG-CoA) reductase inhibitor, simvastatin, to 80 mg/d would affect adrenal and gonadal steroid synthesis in men with hypercholesterolemia. To evaluate this question, we enrolled men into a multicenter randomized, placebo-controlled study lasting 12 weeks. Men with serum low-density lipoprotein cholesterol (LDL-C) more than 145 mg/dL after 6 weeks of a lipid-lowering diet were randomized to 80 mg simvastatin or placebo. Half of the subjects were asked to undergo a 6-hour infusion of corticotropin (ACTH) to evaluate cortisol synthesis, and the entire cohort received a human chorionic gonadotropin (hCG) stimulation test to assess gonadal hormone secretion using pooled serum samples taken 15 minutes apart. A total of 81 men (age, 45 ± 11 years; 93% Caucasian) with baseline serum LDL-C of 197 mg/dL (placebo, n = 39) and 184 mg/dL (simvastatin 80 mg, n = 42) completed the study. After 12 weeks, serum LDL-C, triglycerides, and high-density lipoprotein cholesterol (HDL-C) in the simvastatin group changed by −43%, −25%, and 8%, respectively (all P < .001). The basal cortisol level and the peak serum cortisol and area under the curve response to the 6-hour ACTH infusion were comparable between the two treatment groups at baseline and after 12 weeks. The pooled total testosterone level at baseline was 541 and 513 ng/dL in the placebo and simvastatin-treated groups, respectively, which declined to 536 ± 20.5 ng/dL (−1.5%) and 474 ± 30.4 ng/dL (−13.6%, P = .09) after treatment (mean ± SD). The pooled free testosterone declined by 6.3% in the simvastatin group, versus a 4.9% increase in the placebo group (P = .588), while pooled bioavailable testosterone declined 10.2% in the simvastatin group and increased 1.4% in the placebo group (P = 035). There were no changes in serum gonadotropin levels or sex hormone-binding globulin (SHBG). After administration of hCG, there were no differences in the peak total pooled testosterone level before or after 12 weeks of treatment. Simvastatin 80 mg was well tolerated compared with placebo. In conclusion, basal and stimulated cortisol production was unaffected by the use of simvastatin 80 mg versus placebo. As reported with other statins and cholestyramine, there were small declines in the simvastatin-treated group for pooled total, free, and bioavailable testosterone after 12 weeks, although there was no compensatory increase in serum follicle-stimulating hormone (FSH) or luteinizing hormone (LH) levels.