Apolipoprotein B synthesis inhibition with mipomersen in heterozygous familial hypercholesterolemia: results of a randomized, double-blind, placebo-controlled trial to assess efficacy and safety as add-on therapy in patients with coronary artery disease.

BACKGROUND: Heterozygous familial hypercholesterolemia (HeFH) is a common genetic disorder leading to premature coronary artery disease. Despite statins and additional lipid-lowering therapies, many HeFH patients fail to achieve low-density lipoprotein cholesterol (LDL-C) goals. We evaluated mipomersen, an apolipoprotein B synthesis inhibitor, to further lower LDL-C in HeFH patients with coronary artery disease. METHODS AND RESULTS: This double-blind, placebo-controlled, phase 3 trial randomized patients with HeFH and coronary artery disease on maximally tolerated statin and LDL-C ≥2.6 mmol/L (≥100 mg/dL) to weekly subcutaneous mipomersen 200 mg or placebo (2:1) for 26 weeks. The primary end point was percent change in LDL-C from baseline at week 28. Safety assessments included adverse events, laboratory tests, and magnetic resonance imaging assessment of hepatic fat. Of 124 randomized patients (41 placebo, 83 mipomersen), 114 (41 placebo, 73 mipomersen) completed treatment. Mean (95% confidence interval) LDL-C decreased significantly with mipomersen (-28.0% [-34.0% to -22.1%] compared with 5.2% [-0.5% to 10.9%] increase with placebo; P<0.001). Mipomersen significantly reduced apolipoprotein B (-26.3%), total cholesterol (-19.4%), and lipoprotein(a) (-21.1%) compared with placebo (all P<0.001). No significant change occurred in high-density lipoprotein cholesterol. Adverse events included injection site reactions and influenza-like symptoms. Five mipomersen patients (6%) had 2 consecutive alanine aminotransferase values ≥3 times the upper limit of normal at least 7 days apart; none were associated with significant bilirubin increases. Hepatic fat content increased a median of 4.9% with mipomersen versus 0.4% with placebo (P<0.001). CONCLUSIONS: Mipomersen is an effective therapy to further reduce apolipoprotein B-containing lipoproteins, including LDL and lipoprotein(a), in HeFH patients with coronary artery disease on statins and other lipid-lowering therapy. The significance of hepatic fat and transaminase increases remains uncertain at this time. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00706849.

Efficacy of apolipoprotein B synthesis inhibition in subjects with mild-to-moderate hyperlipidaemia.

AIMS: Mipomersen, an apolipoprotein (apo) B synthesis inhibitor, has been shown to produce potent reductions in apoB and LDL-cholesterol levels in animal models as well as healthy human volunteers. A randomized, double-blind, placebo-controlled, dose-escalation study was designed to evaluate the efficacy and safety of mipomersen monotherapy with or without dose loading in subjects with mild-to-moderate hyperlipidaemia. METHODS AND RESULTS: Fifty subjects with LDL-cholesterol levels between 119 and 266 mg/dL were enrolled into five cohorts at a 4:1 randomization ratio of active to placebo. Two 13-week dose regimens were evaluated at doses ranging from 50 to 400 mg/week. Mipomersen produced dose-dependent reductions in all apoB containing lipoproteins. In the 200 and 300 mg/week dose cohorts, mean reductions from baseline in LDL cholesterol were -45 ± 10% (P= 0.000) and -61 ± 8% (P= 0.000), corresponding to a -46 ± 11% (P= 0.000) and -61 ± 7% (P= 0.000) decrease in apoB levels. Triglyceride levels were also lowered with median reductions up to 53% (P= 0.021). The most common adverse events were injection site reactions. Seven of 40 subjects (18%) showed consecutive transaminase elevations >3× upper limit of normal. Five of these subjects received 400 mg/week, four of whom had apoB levels below the limit of detection. As a consequence, the 400 mg/week cohort was discontinued. CONCLUSIONS: Mipomersen administered as monotherapy in subjects with mild-to-moderate hyperlipidaemia produced potent reductions in all apoB-containing lipoproteins. Higher doses were associated with hepatic transaminase increases.

Effect of mipomersen, an apolipoprotein B synthesis inhibitor, on low-density lipoprotein cholesterol in patients with familial hypercholesterolemia.

A randomized, double-blind, placebo-controlled, dose-escalation study was conducted to examine the efficacy and safety of mipomersen (ISIS 301012), an antisense inhibitor of apolipoprotein B, when added to conventional lipid-lowering therapy for patients with heterozygous familial hypercholesterolemia. A total of 44 patients were enrolled and were separated into 4 cohorts, with doses ranging from 50 to 300 mg (4:1 active treatment/placebo ratio). Patients received 8 doses subcutaneously during a 6-week treatment period. Patients assigned to the 300-mg dose continued for an additional 7 weeks with once-per-week dosing. The primary efficacy end point was the percentage of change from baseline to week 7 in low-density lipoprotein (LDL) cholesterol. Safety was assessed using the laboratory test results and according to the incidence, severity, and relation of adverse events to drug dose. Mipomersen produced significant reductions in LDL cholesterol and other atherogenic apolipoprotein B-containing lipoproteins. After 6 weeks of treatment, the LDL cholesterol level was reduced by 21% from baseline in the 200-mg/week dose group (p <0.05) and 34% from baseline in the 300-mg/week dose group (p <0.01), with a concomitant reduction in apolipoprotein B of 23% (p <0.05) and 33% (p <0.01), respectively. Injection site reactions were the most common adverse event. Elevations in liver transaminase levels (> or =3 times the upper limit of normal) occurred in 4 (11%) of 36 patients assigned to active treatment; 3 of these patients were in the highest dose group. In conclusion, mipomersen has an incremental LDL cholesterol lowering effect when added to conventional lipid-lowering therapy.

Efficacy and safety of mipomersen, an antisense inhibitor of apolipoprotein B, in hypercholesterolemic subjects receiving stable statin therapy.

OBJECTIVES: The aim of this study was to evaluate the efficacy and safety of mipomersen in hypercholesterolemic subjects taking stable statin therapy. BACKGROUND: Mipomersen is an apolipoprotein (apo) B synthesis inhibitor that has demonstrated significant reductions in apo B and low-density lipoprotein (LDL) cholesterol in Phase 1 clinical trials in healthy volunteers. METHODS: A randomized, placebo-controlled, dose-escalation Phase 2 study was designed to evaluate the effects of mipomersen in hypercholesterolemic subjects taking stable statin therapy. Seventy-four subjects were enrolled sequentially into 1 of 6 dose cohorts at a 4:1 (active/placebo) ratio. Subjects received 7 doses of 30 to 400 mg over 5 weeks in the first 5 cohorts and 15 doses of 200 mg over 13 weeks in the sixth cohort. Pre-specified end points included percentage change from baseline in apo B and LDL cholesterol. Safety was assessed with laboratory test results and by the incidence and severity of adverse events. RESULTS: The apo B and LDL cholesterol were reduced by 19% to 54% and 21% to 52%, respectively, at doses of 100 mg/week mipomersen and higher in the 5-week treatment cohorts. Efficacy seemed to increase upon treatment for 13 weeks at a dose of 200 mg/week. Injection site reactions (mild to moderate erythema [90%]) and hepatic transaminase increases (17%) were the most common adverse events, leading to discontinuation in 2 subjects and 1 subject, respectively. In the 13-week treatment cohort, 5 of 10 subjects (50%) had elevations >or=3x the upper limit of normal, 4 of which persisted on 2 consecutive occasions. CONCLUSIONS: Mipomersen might hold promise for treatment of patients not reaching target LDL cholesterol levels on stable statin therapy. Further studies are needed to address the mechanisms and clinical relevance of transaminase changes after mipomersen administration. (Dose-Escalating Safety Study in Subjects on Stable Statin Therapy; NCT00231569).

Mipomersen, an apolipoprotein B synthesis inhibitor, for lowering of LDL cholesterol concentrations in patients with homozygous familial hypercholesterolaemia: a randomised, double-blind, placebo-controlled trial.

BACKGROUND: Homozygous familial hypercholesterolaemia is a rare genetic disorder in which both LDL-receptor alleles are defective, resulting in very high concentrations of LDL cholesterol in plasma and premature coronary artery disease. This study investigated whether an antisense inhibitor of apolipoprotein B synthesis, mipomersen, is effective and safe as an adjunctive agent to lower LDL cholesterol concentrations in patients with this disease. METHODS: This randomised, double-blind, placebo-controlled, phase 3 study was undertaken in nine lipid clinics in seven countries. Patients aged 12 years and older with clinical diagnosis or genetic confirmation of homozygous familial hypercholesterolaemia, who were already receiving the maximum tolerated dose of a lipid-lowering drug, were randomly assigned to mipomersen 200 mg subcutaneously every week or placebo for 26 weeks. Randomisation was computer generated and stratified by weight (<50 kg vs >/=50 kg) in a centralised blocked randomisation, implemented with a computerised interactive voice response system. All clinical, medical, and pharmacy personnel, and patients were masked to treatment allocation. The primary endpoint was percentage change in LDL cholesterol concentration from baseline. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00607373. FINDINGS: 34 patients were assigned to mipomersen and 17 to placebo; data for all patients were analysed. 45 patients completed the 26-week treatment period (28 mipomersen, 17 placebo). Mean concentrations of LDL cholesterol at baseline were 11.4 mmol/L (SD 3.6) in the mipomersen group and 10.4 mmol/L (3.7) in the placebo group. The mean percentage change in LDL cholesterol concentration was significantly greater with mipomersen (-24.7%, 95% CI -31.6 to -17.7) than with placebo (-3.3%, -12.1 to 5.5; p=0.0003). The most common adverse events were injection-site reactions (26 [76%] patients in mipomersen group vs four [24%] in placebo group). Four (12%) patients in the mipomersen group but none in the placebo group had increases in concentrations of alanine aminotransferase of three times or more the upper limit of normal. INTERPRETATION: Inhibition of apolipoprotein B synthesis by mipomersen represents a novel, effective therapy to reduce LDL cholesterol concentrations in patients with homozygous familial hypercholesterolaemia who are already receiving lipid-lowering drugs, including high-dose statins. FUNDING: ISIS Pharmaceuticals and Genzyme Corporation.

Effect of apolipoprotein-B synthesis inhibition on liver triglyceride content in patients with familial hypercholesterolemia.

To investigate the impact of mipomersen, an apolipoprotein B-100 (apoB) synthesis inhibitor, on intra-hepatic triglyceride content (IHTG content), we conducted a randomized, double-blind, placebo-controlled study in 21 patients with familial hypercholesterolemia (FH). Subjects received a weekly subcutaneous dose of 200 mg mipomersen or placebo for 13 weeks while continuing conventional lipid lowering therapy. The primary endpoint was change in IHTG content from week 0 to week 15 as measured by localized proton magnetic resonance spectroscopy (1H-MRS). Thirteen weeks of mipomersen administration reduced LDL-cholesterol by 22.0 (17.8) % and apoB by 19.9 (17.4) % (both P < 0.01). One of 10 patients (10%) in the mipomersen-treated group developed mild hepatic steatosis at week 15, which was reversible following mipomersen discontinuation. For the group, there was a trend toward an increase in IHTG content [placebo; baseline: 1.2% and week 15: 1.1%; change -0.1 (0.9). Mipomersen; baseline: 1.2% and week 15: 2.1%; change 0.8 (1.7) (P = 0.0513)]. Mipomersen administration for 13 weeks to subjects with FH is associated with a trend toward an increase in IHTG content. Future studies evaluating the effects of long-term use of mipomersen reaching more profound reductions in apoB are required prior to broader use of this compound.

Cross-species comparison of in vivo PK/PD relationships for second-generation antisense oligonucleotides targeting apolipoprotein B-100.

The in vivo pharmacokinetics/pharmacodynamics of 2'-O-(2-methoxyethyl) (2'-MOE) modified antisense oligonucleotides (ASOs), targeting apolipoprotein B-100 (apoB-100), were characterized in multiple species. The species-specific apoB antisense inhibitors demonstrated target apoB mRNA reduction in a drug concentration and time-dependent fashion in mice, monkeys, and humans. Consistent with the concentration-dependent decreases in liver apoB mRNA, reductions in serum apoB, and LDL-C, and total cholesterol were concurrently observed in animal models and humans. Additionally, the long duration of effect after cessation of dosing correlated well with the elimination half-life of 2'-MOE modified apoB ASOs studied in mice (t(1/2) congruent with 20 days) and humans (t(1/2) congruent with 30 days) following parental administrations. The plasma concentrations of ISIS 301012, observed in the terminal elimination phase of both mice and monkeys were in equilibrium with liver. The partition ratios between liver and plasma were similar, approximately 6000:1, across species, and thus provide a surrogate for tissue exposure in humans. Using an inhibitory E(max) model, the ASO liver EC(50s) were 101+/-32, 119+/-15, and 300+/-191 microg/g of ASO in high-fat-fed (HF) mice, transgenic mice containing the human apoB transgene, and monkeys, respectively. The estimated liver EC(50) in man, extrapolated from trough plasma exposure, was 81+/-122 microg/g. Therefore, extraordinary consistency of the exposure-response relationship for the apoB antisense inhibitor was observed across species, including human. The cross-species PK/PD relationships provide confidence in the use of pharmacology animal models to predict human dosing for second-generation ASOs targeting the liver.

Lack of pharmacokinetic interaction of mipomersen sodium (ISIS 301012), a 2'-O-methoxyethyl modified antisense oligonucleotide targeting apolipoprotein B-100 messenger RNA, with simvastatin and ezetimibe.

BACKGROUND AND OBJECTIVES: Mipomersen sodium (ISIS 301012) is a 20-mer phosphorothioate antisense oligonucleotide that is complementary to human apolipoprotein B-100 (apoB-100) messenger RNA and subsequently reduces translation of ApoB-100 protein, the major apolipoprotein of very low-density lipoprotein, intermediate-density lipoprotein and low-density lipoprotein (LDL). Mipomersen sodium is currently being studied in phase II/III clinical studies to determine its clinical utility as add-on therapy to HMG-CoA reductase inhibitors or other lipid-lowering agents in subjects with hypercholesterolaemia. The aim of this study was to characterize the pharmacokinetic interactions of mipomersen sodium with simvastatin and ezetimibe. Another aim was to evaluate the ability of mipomersen sodium to inhibit major cytochrome P450 (CYP) isoenzymes in vitro. METHODS: In a phase I clinical study, ten healthy subjects per cohort received a single oral dose of simvastatin 40 mg or ezetimibe 10 mg followed by four 2-hour intravenous doses of mipomersen sodium 200 mg over an 8-day period, with simvastatin 40 mg or ezetimibe 10 mg being administered again with the last dose of mipomersen sodium. Mipomersen sodium pharmacokinetic profiles were assessed following the first dose (mipomersen sodium alone) and the last dose (mipomersen sodium in combination with simvastatin or ezetimibe). Plasma samples for measurement of simvastatin, simvastatin acid, and free and total ezetimibe concentrations were collected at various timepoints following their first and last oral dosing. A comparative pharmacokinetic analysis was performed to determine if there were any effects resulting from coadministration of mipomersen sodium with these lipid-lowering drugs. In addition to the clinical pharmacokinetic analysis, the ability of mipomersen sodium to inhibit the major CYP isoform enzymes (namely CYP1A2, CYP2C9, CYP2C19, CYP2D6 and CYP3A4) was evaluated in cryo-preserved human hepatocytes in vitro. RESULTS: The area under the plasma concentration-time curve (AUC) from 0 to 24 hours (AUC(24)), maximum plasma concentration and apparent elimination half-life values of mipomersen sodium were similar when administered alone and in combination with oral simvastatin or oral ezetimibe. The 90% confidence intervals of the geometric least squares means ratios (%Reference) of the mipomersen sodium AUC(24) values were 93.6, 107 when administered together with simvastatin, and 92.4, 111 when administered with ezetimibe. Therefore, there were no large deviations outside the default no-effect boundaries (80-125%) for total exposure (the AUC) of mipomersen sodium in combination with either simvastatin or ezetimibe. Similarly, large deviations outside the default no-effect boundaries were not observed for simvastatin, simvastatin acid, or free and total ezetimibe exposure in combination with mipomersen sodium. In cryo-preserved human hepatocytes, mipomersen sodium exhibited no cytotoxicity. Significant cell uptake was demonstrated by analysing cell-associated concentrations of mipomersen sodium. All evaluated enzyme activities had <10% inhibition at tested concentrations up to 800 microg/mL (approximately 100 micromol/L) of mipomersen sodium, and dose-dependent inhibition was not observed. Therefore, mipomersen sodium is not considered an inhibitor of CYP1A2, CYP2C9, CYP2C19, CYP2D6 and CYP3A4 enzyme activities. CONCLUSIONS: These data provide evidence that mipomersen sodium exhibits no clinically relevant pharmacokinetic interactions with the disposition and clearance of simvastatin or ezetimibe, and vice versa. Moreover, mipomersen sodium does not inhibit any of the major CYP enzymes that were evaluated. Taken together, the results from this study support the use of mipomersen sodium in combination with oral lipid-lowering agents.

Effects of fenofibrate and ezetimibe, both as monotherapy and in coadministration, on cholesterol mass within lipoprotein subfractions and low-density lipoprotein peak particle size in patients with mixed hyperlipidemia.

Coadministration of fenofibrate and ezetimibe (FENO + EZE) produced complementary and favorable effects on the major lipids and lipoproteins, low-density lipoprotein cholesterol (LDL-C), triglycerides, high-density lipoprotein cholesterol (HDL-C), and non-HDL-C levels, and was well tolerated in patients with mixed hyperlipidemia. The current analysis evaluates the effects of FENO and EZE, as monotherapies and in coadministration, on lipoprotein subfractions and LDL particle size distributions in these patients. In a 12-week, multicenter, randomized, double-blind, placebo-controlled, parallel-group study, patients with mixed hyperlipidemia were randomized in a 1:3:3:3 ratio to one of 4 treatment groups: placebo, FENO 160 mg/day, EZE 10 mg/day, or FENO 160 mg/day + EZE 10 mg/day. At baseline and study end point, the Vertical Auto Profile II method was used to measure the cholesterol associated with 2 very low-density lipoprotein (VLDL) subfractions (VLDL-C1 + 2 and VLDL-C3), intermediate-density lipoproteins (IDL-C), and 4 LDL subfractions (LDL-C1 through LDL-C4, from most buoyant to most dense), lipoprotein (Lp) (a), and 2 HDL-C subfractions (HDL-C2 and HDL-C3). The LDL particle size was determined using segmented gradient gel electrophoresis. Fenofibrate reduced cholesterol mass within VLDL, IDL, and dense LDL (primarily LDL-C4) subfractions, and increased cholesterol mass within the more buoyant LDL-C2 subfraction, consistent with a shift to a more buoyant LDL peak particle size. Ezetimibe reduced cholesterol mass within all of the apolipoprotein B-containing particles (eg, VLDL-C, IDL-C, and LDL-C) but did not lead to a shift in the LDL particle size distribution profile. Coadministration of FENO and EZE promoted more pronounced reductions in VLDL-C, IDL-C, and LDL-C, and a preferential decrease in dense LDL subfractions. Fenofibrate and FENO + EZE promoted similar increases in HDL-C2 and HDL-C3. Coadministration of FENO + EZE produced complementary and favorable changes in lipoprotein fractions and subfractions, as assessed by the Vertical Auto Profile II method, in patients with mixed hyperlipidemia. These changes reflected the combined effects of FENO in reducing triglycerides-rich lipoproteins and promoting a shift in the LDL particle distribution profile toward larger, more buoyant particles and of EZE in promoting reductions in cholesterol mass across the apolipoprotein B particle spectrum.

Effects of ezetimibe/simvastatin on lipoprotein subfractions in patients with primary hypercholesterolemia: an exploratory analysis of archived samples using two commercially available techniques.

BACKGROUND: Cholesterol-rich lipoproteins, including low-density lipoprotein cholesterol (LDL-C), intermediate-density lipoprotein cholesterol (IDL-C), and very-low-density lipoprotein cholesterol (VLDL-C), are known to promote atherosclerosis. Ezetimibe/simvastatin (E/S) is an efficacious lipid-lowering treatment that inhibits both the intestinal absorption and biosynthesis of cholesterol. OBJECTIVE: The aim of the current analysis was to compare the effects of ezetimibe and simvastatin monotherapy and E/S treatment on lipoprotein subfractions and LDL particle size in patients with primary hypercholesterolemia. METHODS: This was an exploratory (hypothesis generating) analysis of archived plasma samples drawn from patients in a multicenter, randomized, double-blind, placebo-controlled, parallel-arm study. After a washout and diet/placebo run-in, patients with hypercholesterolemia (LDL-C, > or =145- < or =250 mg/dL; triglycerides, < or =350 mg/dL) were randomized equally to 1 of 10 daily treatments for 12 weeks: E/S (10/10, 10/20, 10/40, or 10/80 mg), simvastatin monotherapy (10, 20, 40, or 80 mg), ezetimibe monotherapy (10 mg), or placebo. A subset of patients had lipid subfraction measurements taken at baseline (week 0) and postrandomization (week 12). Plasma samples were used to quantify cholesterol associated with VLDL subfractions (VLDLI+2 and VLDL3), IDL, and 4 LDL subfractions (LDL1-4) via the Vertical Auto Profile II method. LDL-C particle size was determined using segmented gradient gel electrophoresis. The primary end point was median percent change in subfraction cholesterol for E/S versus ezetimibe or simvastatin monotherapy, pooled across doses. RESULTS: Of the 1528 patients randomized in the original study, 1397 (91%) had lipid subfraction measurements taken. E/S was associated with significant reductions in VLDL-CI+2, VLDL-C3, IDL-C, LDL-C1, LDL-C2, and LDL-C3 versus ezetimibe, simvastatin, and placebo. E/S resulted in near-additive reductions in VLDL-CI+2, VLDL-C3, IDL-C, LDL-C1, LDL-C2, and LDL-C3 versus ezetimibe and simvastatin monotherapy. Of the subfractions examined, with regard to E/S, the greatest reductions were observed in IDL-C and LDL-C1, LDL-C2, and LDL-C3. When compared with placebo, ezetimibe, simvastatin, and E/S did not shift the distribution of LDL particles toward a larger, more buoyant LDL subclass pattern. CONCLUSION: E/S was more effective than ezetimibe and simvastatin monotherapy in reducing atherogenic lipoprotein subfractions in these patients with primary hypercholesterolemia.

Efficacy and safety of ezetimibe/simvastatin versus simvastatin monotherapy in hypercholesterolemic patients with metabolic syndrome.

BACKGROUND: The combination of ezetimibe and simvastatin (EZE/SIMVA) inhibits intestinal absorption and hepatic synthesis of cholesterol, providing significantly greater LDL-C-lowering compared to either drug alone. We examined the efficacy and safety of EZE/SIMVAin hypercholesterolemic patients with metabolic syndrome (MetS). METHODS: We evaluated pooled data from three similarly designed, randomized, doubleblinded, placebo-controlled studies in patients with primary hypercholesterolemia. After a 6- to 8-week washout and a 4-week diet/placebo run-in, patients received one of the following treatments for 12 weeks: EZE/SIMVA (10/10, 10/20, 10/40 or 10/80 mg); SIMVA (10, 20, 40 or 80 mg); EZE 10 mg; or placebo. For this analysis, the efficacy of EZE/SIMVA versus SIMVA was evaluated in patients with and without MetS. The primary endpoint was mean percent change from baseline in LDL-C for EZE/SIMVA (pooled across doses) versus SIMVA (pooled across doses). RESULTS: Of 2394 patients who received SIMVA or EZE/SIMVA and for whom MetS status at baseline could be determined, 31% were identified as having MetS. In the entire cohort, treatment with EZE/SIMVA led to a significant incremental reduction in low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), apolipoprotein B, triglyceride (TG), and C-reactive protein compared to SIMVA and these effects were similar across the MetS and non-MetS subgroups. EZE/SIMVA was well tolerated in both the MetS and non-MetS subgroups. CONCLUSION: EZE/SIMVA significantly improved the lipid and inflammatory profiles of hypercholesterolemic patients with MetS and was well tolerated. Thus, EZE/SIMVA offers an efficacious and safe treatment option for these patients.

A multicenter, randomized, double-blind, placebo-controlled, factorial design study to evaluate the lipid-altering efficacy and safety profile of the ezetimibe/simvastatin tablet compared with ezetimibe and simvastatin monotherapy in patients with primary hypercholesterolemia.

OBJECTIVE: The purpose of this study was to evaluate the efficacy and safety profile of ezetimibe/simvastatin(EZE/SIMVA) combination tablet, relative to ezetimibe (EZE) and simvastatin (SIMVA) monotherapy, in patients with primary hypercholesterolemia. METHODS: This was a randomized, multicenter, double-blind, placebo-controlled, factorial design study After a 6- to 8-week washout period and 4-week, single-blind, placebo run in, hypercholesterolemic patients (low-density lipoprotein cholesterol [LDL-C], 145-250 mg/dL; triglycerides [TG], < or =350 mg/dL) were randomized equally to 1 of 10 daily treatments for 12 weeks: EZE/SIMVA 10/10, 10/20, 10/40, or 10/80 mg; SIMVA 10, 20, 40, or 80 mg; EZE 10 mg; or placebo. The primary efficacy analysis was mean percent change from baseline in LDL-C to study end point Secondary end points included percent changes in other lipid variables and C-reactive protein [CRP]. RESULTS: There were 1528 patients randomized to treatment (792 women, 736 men); mean (SD) age ranged from 54.9 (112) years to 56.4 (10.6) years across pooled treatment groups. The treatment groups were well balanced for baseline demographics. Pooled EZE/SIMVA was associated with greater reductions in LDL-C than pooled SIMVA or EZE alone (P < 0.001). Depending on dose, EZE/SIMVA was associated with reductions in LDL-C of -44.8% to -602%, non-high-density lipoprotein cholesterol of -40.5% to -55.7%, and TG of -22.5% to -30.7%; high-density lipoprotein cholesterol increased by 5.5% to 9.8%. EZE/SIMVA was associated with greater reductions in CRP and remnant-like particle-cholesterol than SIMVA alone (P < 0.001). More patients receiving EZE/SIMVA versus SIMVA achieved LDL-C concentrations <100 mg/dL (78.6% vs 45.9%; P < 0.001). EZE/SIMVA was generally well tolerated, with a safety profile similar to SIMVA monotherapy There were no significant differences between EZE/SIMVA and SIMVA in the incidence of consecutive liver transaminase levels > or =3 times the upper limit of normal (ULN) (1 .5% for EZE/SIMVA and 1.1% for SIMVA; P = NS) or creature kinase levels > or =10 times ULN (0.0% for EZE/SIMVA and 02% for SIMVA; P = NS). CONCLUSION: The EZE/SIMVA tablet was a highly effective and well-tolerated LDL-C-lowering therapy in this study of patients with primary hypercholesterolemia.

Inhibition of intestinal cholesterol absorption by ezetimibe in humans.

BACKGROUND: Ezetimibe has been shown to inhibit cholesterol absorption in animal models, but studies on cholesterol absorption in humans have not been performed thus far. METHODS AND RESULTS: The effect of ezetimibe (10 mg/d) on cholesterol absorption and synthesis, sterol excretion, and plasma concentrations of cholesterol and noncholesterol sterols was investigated in a randomized, double-blind, placebo-controlled, crossover study in 18 patients with mild to moderate hypercholesterolemia. Treatment periods lasted 2 weeks with an intervening 2-week washout period. Fractional cholesterol absorption rates averaged 49.8+/-13.8% on placebo and 22.7+/-25.8% on ezetimibe, indicating a reduction of 54% (geometric mean ratio; P< 0.001). Cholesterol synthesis increased by 89% from 931+/-1027 mg/d on placebo to 1763+/-1098 mg/d on ezetimibe (P<0.001), while the ratio of lathosterol-to-cholesterol, an indirect marker of cholesterol synthesis, was increased by 72% (P<0.001). Bile acid synthesis was insignificantly increased (placebo: 264+/-209 mg/d, ezetimibe: 308+/-184 mg/d; P=0.068). Mean percent changes from baseline for LDL and total cholesterol after ezetimibe treatment were -20.4% and -15.1%, respectively (P<0.001 for both), whereas campesterol and sitosterol were decreased by -48% and - 41%, respectively. CONCLUSION: In humans, ezetimibe inhibits cholesterol absorption and promotes a compensatory increase of cholesterol synthesis, followed by clinically relevant reductions in LDL and total cholesterol concentrations. Ezetimibe also reduces plasma concentrations of the noncholesterol sterols sitosterol and campesterol, suggesting an effect on the absorption of these compounds as well.