Long-term safety and efficacy of anacetrapib in patients with atherosclerotic vascular disease

AIMS

REVEAL was the first randomized controlled trial to demonstrate that adding cholesteryl ester transfer protein inhibitor therapy to intensive statin therapy reduced the risk of major coronary events. We now report results from extended follow-up beyond the scheduled study treatment period.

METHODS AND RESULTS

A total of 30 449 adults with prior atherosclerotic vascular disease were randomly allocated to anacetrapib 100 mg daily or matching placebo, in addition to open-label atorvastatin therapy. After stopping the randomly allocated treatment, 26 129 survivors entered a post-trial follow-up period, blind to their original treatment allocation. The primary outcome was first post-randomization major coronary event (i.e. coronary death, myocardial infarction, or coronary revascularization) during the in-trial and post-trial treatment periods, with analysis by intention-to-treat. Allocation to anacetrapib conferred a 9% [95% confidence interval (CI) 3-15%; P = 0.004] proportional reduction in the incidence of major coronary events during the study treatment period (median 4.1 years). During extended follow-up (median 2.2 years), there was a further 20% (95% CI 10-29%; P < 0.001) reduction. Overall, there was a 12% (95% CI 7-17%, P < 0.001) proportional reduction in major coronary events during the overall follow-up period (median 6.3 years), corresponding to a 1.8% (95% CI 1.0-2.6%) absolute reduction. There were no significant effects on non-vascular mortality, site-specific cancer, or other serious adverse events. Morbidity follow-up was obtained for 25 784 (99%) participants.

CONCLUSION

The beneficial effects of anacetrapib on major coronary events increased with longer follow-up, and no adverse effects emerged on non-vascular mortality or morbidity. These findings illustrate the importance of sufficiently long treatment and follow-up duration in randomized trials of lipid-modifying agents to assess their full benefits and potential harms.

TRIAL REGISTRATION

International Standard Randomized Controlled Trial Number (ISRCTN) 48678192; ClinicalTrials.gov No. NCT01252953; EudraCT No. 2010-023467-18.

Anacetrapib as lipid-modifying therapy in patients with heterozygous familial hypercholesterolaemia (REALIZE): a randomised, double-blind, placebo-controlled, phase 3 study

BACKGROUND

Present guidelines emphasise the importance of low concentrations of LDL cholesterol (LDL-C) in patients with familial hypercholesterolaemia. In most patients with the disease, however, these concentrations are not achieved with present treatments, so additional treatment is therefore warranted. Inhibition of cholesteryl ester transfer protein has been shown to reduce LDL-C concentrations in addition to regular statin treatment in patients with hypercholesterolaemia or at high risk of cardiovascular disease. We aimed to investigate the safety and efficacy of anacetrapib, a cholesteryl ester transfer protein inhibitor, in patients with heterozygous familial hypercholesterolaemia.

METHODS

In this multicentre, randomised, double-blind, placebo-controlled, phase 3 study, patients aged 18-80 years with a genotype-confirmed or clinical diagnosis of heterozygous familial hypercholesterolaemia, on optimum lipid-lowering treatment for at least 6 weeks, and with an LDL-C concentration of 2·59 mmol/L or higher without cardiovascular disease or 1·81 mmol/L or higher with cardiovascular disease from 26 lipid clinics across nine countries were eligible. We randomly allocated participants with a computer-generated allocation schedule (2:1; block size of six; no stratification) to oral anacetrapib 100 mg or placebo for 52 weeks, with a 12 week post-treatment follow-up afterwards. We masked patients, care providers, and those assessing outcomes to treatment groups throughout the study. The primary outcome was percentage change from baseline in LDL-C concentration. We did analysis using a constrained longitudinal repeated measures model. This trial is registered with ClinicalTrials.gov, number NCT01524289.

FINDINGS

Between Feb 10, 2012, and Feb 12, 2014, we randomly allocated 204 patients to anacetrapib and 102 to placebo. One patient in the anacetrapib group did not receive the drug. At week 52, anacetrapib reduced mean LDL-C concentration from 3·3 mmol/L (SD 0·8) to 2·1 mmol/L (0·8; percentage change 36·0% [95% CI -39·5 to -32·5] compared with an increase with placebo from 3·4 mmol/L (1·2) to 3·5 mmol/L (1·6; percentage change 3·7% [-1·2 to 8·6], with a difference in percentage change between anacetrapib and placebo of -39·7% (95% CI -45·7 to -33·7; p<0·0001). The number of cardiovascular events was increased in patients given anacetrapib compared with those given placebo (4 [2%] of 203 vs none [0%] of 102; p=0·1544), but the proportion with adverse events leading to discontinuation was similar (12 [6%] of 203 vs five [5%] of 102).

INTERPRETATION

In patients with heterozygous familial hypercholesterolaemia, treatment with anacetrapib for 1 year was well tolerated and resulted in substantial reductions in LDL-C concentration. Whether this change leads to a reduction of cardiovascular events will be answered in an outcome study.

FUNDING

Merck & Co, Inc.

Safety and tolerability of extended-release niacin-laropiprant: Pooled analyses for 11,310 patients in 12 controlled clinical trials

BACKGROUND

The Heart Protection Study 2-Treatment of HDL to Reduce the Incidence of Vascular Events (HPS2-THRIVE) showed that adding extended-release niacin-laropiprant (ERN-LRPT) to statin provided no incremental cardiovascular benefit vs placebo (PBO). ERN-LRPT was also associated with an excess of serious adverse experiences (AEs), some of which were unexpected (infections and bleeding). These findings led to the withdrawal of ERN-LRPT from all markets.

OBJECTIVE

We examined the safety profile of ERN-LRPT vs the comparators ERN alone and statins in the ERN-LRPT development program to assess whether similar safety signals were observed to those seen in HPS-THRIVE and whether these might be attributed to ERN or LRPT.

METHODS

Postrandomization safety data from 12 clinical studies, 12 to 52 weeks in duration and involving 11,310 patients, were analyzed across 3 treatments: (1) ERN-LRPT; (2) ERN-NSP (ERN, Merck & Co, Inc or Niaspan [NSP], Abbott Laboratories); and (3) statin-PBO (statin or PBO).

RESULTS

The safety profiles of ERN-LRPT and ERN-NSP were similar, except for less flushing with ERN-LRPT. Nonflushing AEs reported more frequently with ERN-LRPT or ERN-NSP than with statin-PBO were mostly nonserious and typical of niacin (nausea, diarrhea, and increased blood glucose). There was no evidence for an increased risk of serious AEs related to diabetes, muscle, infection, or bleeding.

CONCLUSIONS

Pooled data from 11,310 patients revealed that, except for reduced flushing, the safety profile of ERN-LRPT was similar to that of ERN-NSP; LRPT did not appear to adversely affect the side-effect profile of ERN. The inability to replicate the unexpected AE findings in HPS2-THRIVE could be because of the smaller sample size and substantially shorter duration of these studies.

Effects of anacetrapib on plasma lipids in specific patient subgroups in the DEFINE (Determining the Efficacy and Tolerability of CETP INhibition with AnacEtrapib) trial

BACKGROUND

In the Determining the Efficacy and Tolerability of cholesteryl ester transfer protein (CETP) INhibition with AnacEtrapib (DEFINE) trial, anacetrapib added to statin produced robust low-density lipoprotein cholesterol (LDL-C)-lowering and high-density lipoprotein cholesterol (HDL-C)-raising vs placebo in patients with coronary heart disease (CHD). Predictors of the degree of LDL-C and HDL-C responses to anacetrapib, however, are poorly understood.

OBJECTIVE

Lipid effects of anacetrapib in patient subgroups within the DEFINE trial (clinicaltrials.gov: NCT00685776) are reported.

METHODS

The percent of placebo-corrected changes from baseline for LDL-C (estimated by Friedewald calculation [Fc-LDL-C]) and HDL-C after 24 weeks of anacetrapib 100 mg/day were compared among patients by age, gender, race, diabetes status, type of concomitant statin with or without other lipid therapies, and baseline HDL-C, Fc-LDL-C, and triglyceride (TG) levels.

RESULTS

Percent decreases in Fc-LDL-C and increases in HDL-C with anacetrapib were similar (magnitude of difference generally <1/5 of the overall treatment effect) across subgroups by age, gender, diabetes status, lipid-modifying regimen, and baseline Fc-LDL-C, HDL-C, or TG. On the other hand, anacetrapib effects on Fc-LDL-C (-24% vs -41%) and HDL-C (+75% vs +139%) appeared to be less in black vs white patients, respectively.

CONCLUSION

Effects of anacetrapib on Fc-LDL-C and HDL-C were generally comparable across subgroups, including being relatively independent of baseline Fc-LDL-C, HDL-C, or TG levels. The clinical impact of the lipid-modifying effects of anacetrapib is being evaluated in the cardiovascular disease outcomes trial, Randomized EValuation of the Effects of Anacetrapib though Lipid-modification (REVEAL).

Lipids, Safety Parameters, and Drug Concentrations After an Additional 2 Years of Treatment With Anacetrapib in the DEFINE Study

Anacetrapib is a cholesteryl ester transfer protein (CETP) inhibitor that has previously been shown to reduce low-density lipoprotein cholesterol (LDL-C) and raise high-density lipoprotein cholesterol (HDL-C) in patients with or at high risk of coronary heart disease in the 76-week, placebo-controlled, Determining the Efficacy and Tolerability of CETP Inhibition with Anacetrapib (DEFINE) trial. Here, we report the results of the 2-year extension to the DEFINE study where patients (n = 803) continued on the same assigned treatment as in the original 76-week study. Treatment with anacetrapib during the 2-year extension was well tolerated with a safety profile similar to patients on placebo. No clinically important abnormalities in liver enzymes, blood pressure, electrolytes, or adverse experiences were observed during the extension. At the end of the extension study, relative to the original baseline value, anacetrapib reduced Friedewald-calculated LDL-C by 39.9% and increased HDL-C by 153.3%, compared to placebo. The apparent steady state mean plasma trough concentration of anacetrapib was ∼640 nmol/L. Geometric mean plasma concentrations of anacetrapib did not appear to increase beyond week 40 of the 2-year extension of the 76-week DEFINE base study. In conclusion, an additional 2 years of treatment with anacetrapib were well tolerated with durable lipid-modifying effects on LDL-C and HDL-C.

Evaluation of lipids, drug concentration, and safety parameters following cessation of treatment with the cholesteryl ester transfer protein inhibitor anacetrapib in patients with or at high risk for coronary heart disease

The aim of this study was to assess the effects on lipids and safety during a 12-week reversal period after 18 months of treatment with anacetrapib. The cholesteryl ester transfer protein inhibitor anacetrapib was previously shown to reduce low-density lipoprotein cholesterol by 39.8% (estimated using the Friedewald equation) and increase high-density lipoprotein (HDL) cholesterol by 138.1%, with an acceptable side-effect profile, in patients with or at high risk for coronary heart disease in the Determining the Efficacy and Tolerability of CETP Inhibition With Anacetrapib (DEFINE) trial. A total of 1,398 patients entered the 12-week reversal-phase study, either after completion of the active-treatment phase or after early discontinuation of the study medication. In patients allocated to anacetrapib, placebo-adjusted mean percentage decreases from baseline were observed at 12 weeks off the study drug for Friedewald-calculated low-density lipoprotein cholesterol (18.6%), non-HDL cholesterol (17.6%), and apolipoprotein B (10.2%); placebo-adjusted mean percentage increases were observed for HDL cholesterol (73.0%) and apolipoprotein A-I (24.5%). Residual plasma anacetrapib levels (about 40% of on-treatment apparent steady-state trough levels) were also detected 12 weeks after cessation of anacetrapib. No clinically important elevations in liver enzymes, blood pressure, electrolytes, or adverse experiences were observed during the reversal phase. Preliminary data from a small cohort (n = 30) revealed the presence of low concentrations of anacetrapib in plasma 2.5 to 4 years after the last anacetrapib dose. In conclusion, after the cessation of active treatment, anacetrapib plasma lipid changes and drug levels decreased to approximately 40% of on-treatment trough levels at 12 weeks after dosing, but modest HDL cholesterol elevations and low drug concentrations were still detectable 2 to 4 years after the last dosing.

Measurement of LDL-C after treatment with the CETP inhibitor anacetrapib

Estimation of low-density lipoprotein cholesterol (LDL-C) using the Friedewald (FR) formula is often inaccurate when triglycerides are elevated or VLDL particle composition is altered. We hypothesized that LDL-C estimation by the FR formula and other measurement methods might also be inaccurate in individuals treated with a cholesteryl ester transfer protein (CETP) inhibitor. An assay comparison study was conducted using pre and posttreatment serum samples from 280 of the 811 patients treated with the CETP inhibitor anacetrapib in the DEFINE study (determining the efficacy and tolerability of CETP inhibition with anacetrapib). After 24 weeks of treatment with anacetrapib, mean LDL-C values by FR formula, Roche direct method (RDM) and Genzyme direct method (GDM) deviated from that measured by the β-quantification (BQ) reference method by -12.2 ± 7.5, -10.2 ± 6.6, -10.8 ± 8.8 mg/dl, respectively. After treatment with anacetrapib, the FR formula and detergent-based direct methods provided lower LDL-C values than those obtained by the BQ reference method. The bias by the FR formula appeared to be due to an overestimation of VLDL-C by the TG/5 component of the formula. Evaluation of the clinical significance of these findings awaits comprehensive lipid and cardiovascular outcome data from ongoing Phase III clinical studies of anacetrapib.

Effects of coadministered extended-release niacin/laropiprant and simvastatin on lipoprotein subclasses in patients with dyslipidemia

BACKGROUND

The use of extended-release niacin and the prostaglandin D₂ receptor antagonist laropiprant (ERN/LRPT) reduces niacin-induced flushing in patients while preserving its lipid-modifying effects.

OBJECTIVE

This predefined exploratory analysis examined the individual and combined effects of ERN/LRPT and simvastatin (SIM) on lipoprotein subclasses.

METHODS

This double-blind study randomized 1398 dyslipidemic patients equally to ERN/LRPT 1 g/20 mg, SIM (10, 20, or 40 mg), or ERN/LRPT 1 g/20 mg + SIM (10, 20, or 40 mg) once daily for 4 weeks. At week 5, doses were doubled, except SIM 40 mg (unchanged) and ERN/LRPT 1 g/20 mg + SIM 40 mg (switched to ERN/LRPT 2 g/40 mg + SIM 40 mg). Cholesterol associated with lipoprotein subclasses was quantified by vertical auto profile II (VAP II).

RESULTS

ERN/LRPT + SIM and SIM alone lowered LDL-C 1 and 3, whereas the effects were variable for ERN/LRPT; all three treatments increased LDL-C 4. ERN/LRPT + SIM and ERN/LRPT raised HDL-C 2 and 3, with greater relative percent changes in HDL 2 than HDL 3. ERN/LRPT + SIM for 12 weeks produced substantial reductions in IDL-C, which was additive compared with each monotherapy.

CONCLUSION

Coadministered ERN/LRPT + SIM produced marked reductions in atherogenic lipoproteins, with the greatest effect on IDL-C, and increases in protective HDL subclasses.

Safety of anacetrapib in patients with or at high risk for coronary heart disease

BACKGROUND

Anacetrapib is a cholesteryl ester transfer protein inhibitor that raises high-density lipoprotein (HDL) cholesterol and reduces low-density lipoprotein (LDL) cholesterol.

METHODS

We conducted a randomized, double-blind, placebo-controlled trial to assess the efficacy and safety profile of anacetrapib in patients with coronary heart disease or at high risk for coronary heart disease. Eligible patients who were taking a statin and who had an LDL cholesterol level that was consistent with that recommended in guidelines were assigned to receive 100 mg of anacetrapib or placebo daily for 18 months. The primary end points were the percent change from baseline in LDL cholesterol at 24 weeks (HDL cholesterol level was a secondary end point) and the safety and side-effect profile of anacetrapib through 76 weeks. Cardiovascular events and deaths were prospectively adjudicated.

RESULTS

A total of 1623 patients underwent randomization. By 24 weeks, the LDL cholesterol level had been reduced from 81 mg per deciliter (2.1 mmol per liter) to 45 mg per deciliter (1.2 mmol per liter) in the anacetrapib group, as compared with a reduction from 82 mg per deciliter (2.1 mmol per liter) to 77 mg per deciliter (2.0 mmol per liter) in the placebo group (P<0.001)--a 39.8% reduction with anacetrapib beyond that seen with placebo. In addition, the HDL cholesterol level increased from 41 mg per deciliter (1.0 mmol per liter) to 101 mg per deciliter (2.6 mmol per liter) in the anacetrapib group, as compared with an increase from 40 mg per deciliter (1.0 mmol per liter) to 46 mg per deciliter (1.2 mmol per liter) in the placebo group (P<0.001)--a 138.1% increase with anacetrapib beyond that seen with placebo. Through 76 weeks, no changes were noted in blood pressure or electrolyte or aldosterone levels with anacetrapib as compared with placebo. Prespecified adjudicated cardiovascular events occurred in 16 patients treated with anacetrapib (2.0%) and 21 patients receiving placebo (2.6%) (P = 0.40). The prespecified Bayesian analysis indicated that this event distribution provided a predictive probability (confidence) of 94% that anacetrapib would not be associated with a 25% increase in cardiovascular events, as seen with torcetrapib.

CONCLUSIONS

Treatment with anacetrapib had robust effects on LDL and HDL cholesterol, had an acceptable side-effect profile, and, within the limits of the power of this study, did not result in the adverse cardiovascular effects observed with torcetrapib. (Funded by Merck Research Laboratories; ClinicalTrials.gov number, NCT00685776.).

Safety of extended-release niacin/laropiprant in patients with dyslipidemia

OBJECTIVE

To evaluate the safety profile of extended-release niacin/laropiprant (ERN/LRPT), pooling data from studies in the clinical development program.

METHODS

Data were pooled from three active- or placebo-controlled phase 3 studies and three 1-year extensions of phase 2 studies that ranged from 12 to 52 weeks (N = 4747): ERN/LRPT = 2548; ERN or Niaspan® (ERN-NSP = 1268); or simvastatin or placebo (SIMVA-PBO = 931).

RESULTS

The safety and tolerability profile for ERN/LRPT was similar to that of ERN-NSP, except for fewer flushing-related adverse experiences and discontinuations with ERN/LRPT than ERN-NSP. The incidence of consecutive ≥3× the upper limit of normal increases in alanine aminotransferase and/or aspartate aminotransferase was numerically (but not statistically) greater with ERN/LRPT (1.0%) than ERN-NSP (0.5%) and similar to SIMVA-PBO (0.9%). Elevations were reversible with therapy discontinuation and not associated with clinical hepatotoxicity. There was no evidence that ERN/LRPT administered alone or concurrently with a statin had adverse effects on muscle. ERN/LRPT and ERN-NSP produced small median increases in fasting blood glucose levels (∼4 mg/dL) after 24 weeks of treatment, consistent with known effects of niacin.

CONCLUSION

The favorable safety and tolerability profile of ERN/LRPT for up to 1 year supports the use of LRPT to achieve improved therapeutic dosing of niacin, an agent with comprehensive lipid-modifying efficacy and shown to reduce cardiovascular risk.

Design of the DEFINE trial: determining the EFficacy and tolerability of CETP INhibition with AnacEtrapib

BACKGROUND

Residual cardiovascular (CV) risk often remains high despite statin therapy to lower low-density lipoprotein cholesterol (LDL-C). New therapies to raise high-density lipoprotein cholesterol (HDL-C) are currently being investigated. Anacetrapib is a cholesteryl ester transfer protein (CETP) inhibitor that raises HDL-C and reduces LDL-C when administered alone or with a statin. Adverse effects on blood pressure, electrolytes, and aldosterone levels, seen with another drug in this class, have not been noted in studies of anacetrapib to date.

METHODS

Determining the EFficacy and Tolerability of CETP INhibition with AnacEtrapib (DEFINE) is a randomized, double-blind, placebo-controlled trial to assess the efficacy and safety profile of anacetrapib in patients with coronary heart disease (CHD) or CHD risk equivalents (clinical trials.gov NCT00685776). Eligible patients at National Cholesterol Education Program-Adult Treatment Panel III LDL-C treatment goal on a statin, with or without other lipid-modifying medications, are treated with anacetrapib, 100 mg, or placebo for 18 months, followed by a 3-month, poststudy follow-up. The primary end points are percent change from baseline in LDL-C and the safety and tolerability of anacetrapib. Comprehensive preplanned interim safety analyses will be performed at the 6- and 12-month time points to examine treatment effects on key safety end points, including blood pressure and electrolytes. A preplanned Bayesian analysis will be performed to interpret the CV event distribution, given the limited number of events expected in this study.

RESULTS

A total of 2,757 patients were screened at 153 centers in 20 countries, and 1,623 patients were randomized into the trial. Lipid results, clinical CV events, and safety outcomes from this trial are anticipated in 2010.

Flushing profile of extended-release niacin/laropiprant versus gradually titrated niacin extended-release in patients with dyslipidemia with and without ischemic cardiovascular disease

Niacin has beneficial effects on a patient's lipid and lipoprotein profiles and cardiovascular risk, particularly at doses >2 g/day, but is underused due to flushing. Laropiprant (LRPT), a selective prostaglandin D(2) receptor-1 antagonist, decreases flushing associated with extended-release niacin (ERN). We compared flushing with ERN/LRPT dosed by a simplified 1-g --> 2-g regimen versus gradually titrated niacin extended-release (N-ER; given as NIASPAN, trademark of Kos Life Sciences LLC). Patients with dyslipidemia (n = 1,455) were randomized 1:1 to ERN/LRPT (1 g for 4 weeks advanced to 2 g for 12 weeks) or N-ER (0.5 g for 4 weeks titrated in 0.5-g increments every 4 weeks to 2 g for the final 4 weeks). Aspirin/nonsteroidal anti-inflammatory drugs were allowed to mitigate flushing. Flushing severity was assessed using the validated Global Flushing Severity Score (GFSS; none 0, mild 1 to 3, moderate 4 to 6, severe 7 to 9, extreme 10). Patients on ERN/LRPT, despite more rapid niacin titration, had less flushing than those on N-ER, as measured by number of days per week with moderate or greater GFSS across the treatment period (p <0.001). More than 2 times as many patients had no episodes of moderate, severe, or extreme flushing (GFSS > or =4) with ERN/LRPT than with N-ER (47.0% vs 22.0%, respectively) across the treatment period. Fewer patients on ERN/LRPT discontinued due to flushing than those on N-ER (7.4% vs 12.4%, p = 0.002). Other than the decrease in flushing, the safety and tolerability profile of ERN/LRPT was similar to that of N-ER. In conclusion, improvement in flushing with ERN/LRPT versus gradually titrated N-ER supports a rapidly advanced 1-g --> 2-g dosing regimen, allowing patients to start at 1 g and quickly reach and tolerate the optimal 2 g dose of ERN.

Efficacy and safety of the cholesteryl ester transfer protein inhibitor anacetrapib as monotherapy and coadministered with atorvastatin in dyslipidemic patients

BACKGROUND

High-density lipoprotein cholesterol (HDL-C) levels are inversely associated with cardiovascular risk. Cholesteryl ester transfer protein inhibition is one strategy for increasing HDL-C. This study evaluated the lipid-altering efficacy and safety of the cholesteryl ester transfer protein inhibitor anacetrapib as monotherapy or coadministered with atorvastatin in patients with dyslipidemia.

METHODS

A total of 589 patients with primary hypercholesterolemia or mixed hyperlipidemia (53.8% of the study population had low HDL-C) were randomized equally to one of 10 groups: 5 groups received background statin therapy of atorvastatin 20 mg and 5 did not, and each of these was randomized to placebo, anacetrapib 10, 40, 150, and 300 mg once daily for 8 weeks. An equal proportion of patients had triglycerides >150 mg/dL in each group.

RESULTS

For placebo and anacetrapib monotherapy (10, 40, 150, and 300 mg), least squares mean percent changes from baseline to week 8 for low-density lipoprotein cholesterol (LDL-C) were 2%, -16%, -27%, -40%, and -39%, respectively, and for HDL-C were 4%, 44%, 86%, 139%, and 133%, respectively (P < .001 vs placebo for all doses). Coadministration of anacetrapib with atorvastatin produced significant incremental LDL-C reductions and similar HDL-C increases versus atorvastatin monotherapy. For both anacetrapib monotherapy and coadministration with atorvastatin, the LDL-C reductions were similar in patients with baseline triglyceride levels greater than and less than or equal to the median. Anacetrapib was well tolerated, and the incidence of adverse events was similar for placebo and all active treatment groups. There were no increases in systolic or diastolic blood pressure in any treatment arm.

CONCLUSIONS

Anacetrapib, as monotherapy or coadministered with atorvastatin, produced significant reductions in LDL-C and increases in HDL-C; the net result of treatment with anacetrapib + atorvastatin was approximately 70% lowering of LDL-C and more than doubling of HDL-C. Anacetrapib was generally well tolerated with no discernable effect on blood pressure.

Lipid-modifying efficacy and tolerability of extended-release niacin/laropiprant in patients with primary hypercholesterolaemia or mixed dyslipidaemia

BACKGROUND

Improving lipids beyond low-density lipoprotein cholesterol (LDL-C) lowering with statin monotherapy may further reduce cardiovascular risk. Niacin has complementary lipid-modifying efficacy to statins and cardiovascular benefit, but is underutilised because of flushing, mediated primarily by prostaglandin D(2) (PGD(2)). Laropiprant (LRPT), a PGD(2) receptor (DP1) antagonist that reduces niacin-induced flushing has been combined with extended-release niacin (ERN) into a fixed-dose tablet.

METHODS AND RESULTS

Dyslipidaemic patients were randomised to ERN/LRPT 1 g (n = 800), ERN 1 g (n = 543) or placebo (n = 270) for 4 weeks. Doses were doubled (2 tablets/day; i.e. 2 g for active treatments) for 20 weeks. ERN/LRPT 2 g produced significant changes vs. placebo in LDL-C (-18.4%), high-density lipoprotein cholesterol (HDL-C; 20.0%), LDL-C:HDL-C (-31.2%), non-HDL-C (-19.8%), triglycerides (TG; -25.8%), apolipoprotein (Apo) B (-18.8%), Apo A-I (6.9%), total cholesterol (TC; -8.5%), TC:HDL-C (-23.1%) and lipoprotein(a) (-20.8%) across weeks 12-24. ERN/LRPT produced significantly less flushing than ERN during initiation (week 1) and maintenance (weeks 2-24) for all prespecified flushing end-points (incidence, intensity and discontinuation because of flushing). Except for flushing, ERN/LRPT had a safety/tolerability profile comparable with ERN.

CONCLUSION

Extended-release niacin/LRPT 2 g produced significant, durable improvements in multiple lipid/lipoprotein parameters. The improved tolerability of ERN/LRPT supports a simplified 1 g-->2 g dosing regimen of niacin, a therapy proven to reduce cardiovascular risk.

Effects of a niacin receptor partial agonist, MK-0354, on plasma free fatty acids, lipids, and cutaneous flushing in humans

BACKGROUND

Development of niacin-like agents that favorably affect lipids with an improved flushing profile would be beneficial.

OBJECTIVE

To evaluate a niacin receptor partial agonist, MK-0354, in Phase I and II studies.

METHODS

The pharmacokinetic/pharmacodynamic effects of single and multiple doses (7 days) of MK-0354 (300-4000 mg) were evaluated in two Phase I studies conducted in healthy men. A Phase II study assessed the effects of MK-0354 2.5 g once daily on lipids during 4 weeks in 66 dyslipidemic patients.

RESULTS

MK-0354 single doses up to 4000 mg and multiple doses (7 days) up to 3600 mg produced robust dose-related reductions in free fatty acid (FFA) over 5 hours. Single doses of MK-0354 300 mg and extended release-niacin (Niaspan) 1 g produced comparable reductions in FFA. Suppression of FFA following 7 daily doses of MK-0354 was similar to that after a single dose. In the Phase II study, MK-0354 2.5 g produced little flushing but no clinically meaningful effects on lipids (placebo-adjusted percent change: high-density lipoprotein cholesterol, 0.4%, 95% confidence interval -5.2 to 6.0; low-density lipoprotein cholesterol, -9.8%, 95% confidence interval -16.8 to -2.7; triglyceride, -5.8%, 95% confidence interval -22.6 to 11.9).

CONCLUSION

Treatment with MK-0354 for 7 days resulted in plasma FFA suppression with minimal cutaneous flushing. However, 4 weeks of treatment with MK-0354 failed to produce changes in high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, or triglycerides.

Comparison of the lipid-modifying efficacy and safety profiles of ezetimibe coadministered with simvastatin in older versus younger patients with primary hypercholesterolemia: A post Hoc analysis of subpopulations from three pooled clinical trials

BACKGROUND

Despite the need for effective and well-tolerated lipid-lowering therapies for primary hypercholesterolemia in older patients, there is a relative paucity of published data on such treatments in this population.

OBJECTIVE

We conducted a post hoc analysis to examine the lipid-modifying efficacy and safety profile of simvastatin (SIMVA) monotherapy, and the coadministration of ezetimibe (EZE) and SIMVA (EZE/SIMVA) in older (ie, aged>or=65 years) versus younger (ie, aged<65 years) patients with primary hypercholesterolemia.

METHODS

We analyzed pooled data from 3 previously published, similarly designed, randomized, double-blind, placebo-controlled studies in patients with primary hypercholesterolemia. After a 6- to 8-week washout, a 4-week dietary stabilization period, and a 4-week placebo run-in period, patients with low-density lipoprotein cholesterol (LDL-C) of 145 to 250 mg/dL were randomized to 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 12 weeks. In this post hoc analysis, the percent change from baseline to week 12 in LDL-C, high-density lipoprotein cholesterol (HDL-C), non-HDL-C, apolipoprotein B (apo B), triglycerides (TG), and high-sensitivity C-reactive protein (hs-CRP) for EZE/SIMVA (pooled across doses) versus SIMVA alone (pooled across doses) was compared between older and younger patients with primary hypercholesterolemia. Tolerability was assessed by adverse event reports and laboratory and vital signs assessments throughout the study.

RESULTS

A total of 3083 patients aged 20 to 87 years were included in the 3 studies (2320 were aged<65 years and 763 were aged>or=65 years). Baseline lipid values and patient characteristics were similar among all treatment groups for patients aged<65 years versus those aged>or=65 years except that there was a higher percentage of females (62% vs 50%) and patients with hypertension (46% vs 29%) in the older versus younger subgroup (both, P<0.001). EZE/SIMVA was associated with greater improvements than SIMVA alone in LDL-C, non-HDL-C, apo B, TG, and hs-CRP (all, P<0.001); these effects did not appear to differ between the older and younger sub-groups (all, P=NS). Changes in HDL-C did not differ significantly between the EZE/SIMVA and SIMVA groups. More patients receiving EZE/SIMVA than SIMVA monotherapy achieved the target LDL-C level<100 mg/dL (P<0.001), regardless of age subgroup (77% vs 41% for patients aged<65 years and 85% vs 48% for patients aged>or=65 years). In the younger sub-group, the incidence of creatinine phosphokinase (CK) elevations>or=10x the upper limit of normal (ULN) was <I% in the placebo, SIMVA, and EZE/SIMVA groups and 0% in the EZE group; in the older subgroup, no CK elevations>or=10x ULN were reported. In younger patients, the incidence of consecutive alanine amino-transferase or aspartate aminotransferase levels>or=3x ULN was 0% for placebo and EZE, <1% for SIMVA, and 2% for EZE/SIMVA; in older patients, it was 1% for placebo and EZE, <1% for SIMVA, and 0% for EZE/SIMVA.

CONCLUSION

This post hoc analysis of pooled data from 3 previously published large clinical trials suggests that EZE/SIMVA was well tolerated and associated with improved lipid profiles in both older and younger patients with primary hypercholesterolemia.

Consistency of lipid-altering effects of ezetimibe/simvastatin across gender, race, age, baseline low density lipoprotein cholesterol levels, and coronary heart disease status: results of a pooled retrospective analysis

BACKGROUND

The combination tablet containing ezetimibe and simvastatin (EZE/SIMVA), inhibits both the intestinal absorption and endogenous production of cholesterol, providing significantly greater low-density lipoprotein cholesterol (LDL-C) lowering than EZE or SIMVA alone. The purpose of this pooled analysis was to evaluate the consistency of efficacy (i.e., between-treatment difference) of EZE/SIMVA versus SIMVA within several selected subgroups of patients with primary hypercholesterolemia.

METHODS

For the present analysis, data were pooled from three similarly designed, 12-week, randomized, double-blind, placebo-controlled factorial studies consisting of 3083 patients with primary hypercholesterolemia (n = 311 in placebo group; n = 302 in EZE group; n = 1234 in pooled SIMVA group; n = 1236 in pooled EZE/SIMVA group). In these clinical studies, primary hypercholesterolemia was defined as an LDL-C value between 145 and 250 mg/dL inclusive and a triglyceride (TG) level of less than 350 mg/dL. The results for the pooled SIMVA and pooled EZE/SIMVA groups were used for the present analyses. The pooled analyses focused on the consistency of the between-treatment differences (i.e., incremental effect) for EZE/SIMVA (pooled across doses) versus SIMVA (pooled across doses) on various lipid and non-lipid parameters within different patient subgroups defined according to gender, race (Caucasian, Non-Caucasian), baseline age (< 65, > or = 65 years), baseline LDL-C (< 160, > or = 160 mg/dL), and coronary heart disease (CHD) history. Tolerability was also examined for pooled EZE/SIMVA and pooled SIMVA within these selected subgroups. In a modified intention-to-treat analysis, an ANOVA model was used for testing the consistency of pooled treatment effects on lipid and non-lipid parameters within each selected subgroup.

RESULTS

For the entire cohort, baseline lipid profiles were similar for the patients in the pooled EZE/SIMVA group compared with those in the pooled SIMVA group. Treatment with EZE/SIMVA led to significant (p < 0.001) incremental improvements in LDL-C, non-high density lipoprotein cholesterol (non-HDL-C), apolipoprotein B, TG and high sensitivity C-reactive protein compared to SIMVA, across the entire cohort. These changes were consistent within each of the selected subgroups. Moreover, more patients attained LDL-C goal levels < 100 mg/dL with EZE/SIMVA than with SIMVA in the entire cohort and this was consistent across all subgroups, except baseline LDL-C. In this pooled retrospective analysis, treatment with EZE/SIMVA was generally well tolerated across subgroups, with a safety profile similar to SIMVA monotherapy. Although this pooled analysis was performed on a large cohort of patients with primary hypercholesterolemia, the results of this analysis were specific for this select patient population and generalizations to other populations should be applied with caution.

CONCLUSION

The enhanced lipid-altering effects of EZE/SIMVA versus those of SIMVA observed in the entire cohort were consistent within all subgroups examined. EZE/SIMVA represents an effective and well-tolerated therapeutic option for the treatment of a wide range of patient subgroups with primary hypercholesterolemia.

Efficacy and safety of ezetimibe co-administered with simvastatin in thiazolidinedione-treated type 2 diabetic patients

AIM

In patients with type 2 diabetes mellitus (T2DM), combination therapy is usually required to optimize glucose metabolism as well as to help patients achieve aggressive targets for low-density lipoprotein cholesterol (LDL-C) and other lipid parameters associated with cardiovascular risk. The thiazolidinediones (TZDs) are increasingly being used for both their blood glucose-lowering properties and their modest beneficial effects on triglycerides (TG) and high-density lipoprotein cholesterol (HDL-C). Ezetimibe, an intestinal cholesterol absorption inhibitor, has a mechanism of action that differs from that of statins, which inhibit hepatic cholesterol synthesis. We compared the lipid-modifying efficacy and safety of adding ezetimibe to simvastatin, vs. doubling the dose of simvastatin, in TZD-treated T2DM patients.

METHODS

This was a randomized, double-blind, parallel group, multicentre study in T2DM patients, 30-75 years of age, who had been on a stable dose of a TZD for at least 3 months and had LDL-C > 2.6 mmol/l (100 mg/dl) prior to study entry. Other antidiabetic medications were also allowed. Following 6 weeks of open-label simvastatin 20 mg/day, patients were randomized to the addition of either blinded ezetimibe 10 mg/day (n = 104) or an additional blinded simvastatin 20 mg/day (total simvastatin 40 mg/day; n = 110) for 24 weeks. Patients were stratified according to TZD type and dose (pioglitazone 15-30 vs. 45 mg/day; rosiglitazone 2-4 vs. 8 mg/day).

RESULTS

LDL-C was reduced more (p < 0.001) by adding ezetimibe 10 mg to simvastatin 20 mg (-20.8%) than by doubling the dose of simvastatin to 40 mg (-0.3%). Ezetimibe plus simvastatin 20 mg also produced significant incremental reductions in non-HDL-C (p < 0.001), very low-density lipoprotein cholesterol (p < 0.05) and apolipoprotein B (p < 0.001) relative to simvastatin 40 mg. There were no differences between the groups with respect to changes in TG and HDL-C levels, and both treatments were well tolerated.

CONCLUSIONS

Co-administration of ezetimibe with simvastatin, a dual inhibition treatment strategy targeting both cholesterol synthesis and absorption, is well tolerated and provides greater LDL-C-lowering efficacy than increasing the dose of simvastatin in T2DM patients taking TZDs.

Effects of ezetimibe coadministered with simvastatin on C-reactive protein in a large cohort of hypercholesterolemic patients

OBJECTIVE

This study assessed the effect of coadministration of ezetimibe and simvastatin on high sensitivity C-reactive protein (hs-CRP) in a large subject cohort (N=1089).

METHODS

Data were combined from two nearly identical prospective trials. After dietary stabilization, washout period, and placebo lead-in period, patients with baseline low-density lipoprotein cholesterol (LDL-C) > or =3.75-6.50 mmol/l and triglycerides (TG) < or =4.0 mmol/l were randomized to one of the following daily treatments for 12 weeks: ezetimibe 10 mg; simvastatin monotherapy (10, 20, 40, or 80 mg); ezetimibe 10mg plus simvastatin (10, 20, 40, or 80 mg); or placebo. The primary analysis was the percent change in hs-CRP for the pooled ezetimibe plus simvastatin versus simvastatin monotherapy cohorts.

RESULTS

Ezetimibe coadministered with simvastatin more than doubled the hs-CRP reduction compared to simvastatin monotherapy (-33.3% versus -14.3%, p<0.01). At each individual simvastatin dose level, coadministration therapy exerted significant further incremental hs-CRP reductions compared to simvastatin monotherapy. Similar hs-CRP reductions with coadministered ezetimibe and simvastatin were observed in the major subgroups examined (coronary heart disease, gender, age, baseline LDL-C, and body mass index).

CONCLUSION

In this large subject cohort, ezetimibe coadministered with simvastatin significantly reduced hs-CRP, suggesting a possible additional anti-inflammatory/anti-atherosclerotic action of combination therapy compared to simvastatin monotherapy.

Treatment of high-risk patients with ezetimibe plus simvastatin co-administration versus simvastatin alone to attain National Cholesterol Education Program Adult Treatment Panel III low-density lipoprotein cholesterol goals

This study assessed whether the co-administration of ezetimibe and simvastatin would be more effective than simvastatin monotherapy in allowing high-risk patients to achieve a low-density lipoprotein (LDL) cholesterol goal of <100 mg/dl. Men and women with LDL cholesterol >/=130 mg/dl and meeting National Cholesterol Education Program Adult Treatment Panel III criteria for coronary heart disease (CHD) or CHD risk equivalent were randomized to 1 of 4 daily treatments for 23 weeks: simvastatin 20 mg (n = 253), ezetimibe 10 mg plus simvastatin 10 mg (n = 251), ezetimibe 10 mg plus simvastatin 20 mg (n = 109), and ezetimibe 10 mg plus simvastatin 40 mg (n = 97). In all groups, patients not at goal had their simvastatin doses doubled at weeks 6, 12, and/or 18, up to a maximum of 80 mg. The primary efficacy objective was LDL cholesterol goal attainment (<100 mg/dl) after 5 weeks of treatment. Ezetimibe plus any dose of simvastatin produced greater reductions in LDL cholesterol and allowed more patients to achieve goal after 5 weeks (p <0.001) and at the end of the study (p <0.001) than simvastatin 20 mg alone. At 5 weeks, 75%, 83%, and 87% of patients receiving ezetimibe plus simvastatin 10, 20, and 40 mg had LDL cholesterol <100 mg/dl compared with 46% of patients receiving simvastatin 20 mg. In patients who started on ezetimibe plus simvastatin 10, 20 and 40 mg, 33%, 22%, and 12%, respectively, required simvastatin titration during the study compared with 68% of patients who started on simvastatin 20 mg. The corresponding median simvastatin doses used were 10, 20, 40, and 40 mg, respectively. Ezetimibe plus simvastatin was well tolerated, with an overall safety profile similar to that of simvastatin monotherapy. Thus, through the dual inhibition of cholesterol absorption and synthesis, ezetimibe plus simvastatin allowed more patients to reach LDL cholesterol <100 mg/dl at a lower simvastatin dose and with fewer dose titrations than simvastatin monotherapy.

Lowering low density lipoprotein cholesterol with simvastatin, a hydroxy-3-methylglutaryl-coenzyme a reductase inhibitor, does not affect luteal function in premenopausal women

In this double-blind, randomized, placebo-controlled study, normally cycling women (n = 86) with elevated low density lipoprotein cholesterol (LDL-C) levels were studied over six menstrual cycles. At the end of the screening phase, participants received placebo for the second menstrual cycle and subsequently were randomized to receive either placebo or simvastatin (40 mg/d) for the next four cycles. The second and sixth menstrual cycles were considered baseline and treatment cycles, respectively. Participants kept a menstrual diary throughout the study and provided daily first-void urine samples during cycles 2 and 6. Urine samples were assayed for LH and pregnanediol glucuronide (PdG). The primary end point was change in luteal phase duration as defined by the day of the urinary LH peak to the day preceding the onset of menstruation. Treatment with simvastatin (40 mg/d) effectively lowered LDL-C by 34.3% (P < 0.001). Simvastatin was generally well tolerated, and no meaningful difference in adverse event profile was observed between treatment groups. Compared with the placebo group, simvastatin did not have clinically relevant effects on luteal phase duration, peak PdG concentration, or integrated luteal phase PdG concentration. The results of this study demonstrate that treatment of healthy premenopausal women for approximately 4 months with simvastatin (40 mg/d) lowers LDL-C without adversely affecting reproductive gonadal function. Simvastatin should not be used during pregnancy or by nursing mothers.

Effects of high-dose simvastatin on adrenal and gonadal steroidogenesis in men with hypercholesterolemia

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.

Effect of cholesterol-lowering therapy on coronary endothelial vasomotor function in patients with coronary artery disease

BACKGROUND

Improved endothelial function may contribute to the beneficial effects of cholesterol-lowering therapy.

METHODS AND RESULTS

In this randomized, double-blind study, we compared the effect of 6 months of simvastatin (40 mg/d) treatment with that of placebo on coronary endothelial vasomotor function in 60 patients with coronary artery disease. Simvastatin lowered LDL-cholesterol by 40+/-12% from 130+/-28 mg/dL (P<0.001). Peak intracoronary acetylcholine infusion produced epicardial coronary constriction at baseline in both the simvastatin (-17+/-13%) and placebo (-24+/-16%) groups. After treatment, acetylcholine produced less constriction in both groups (-12+/-19% and -15+/-14%, respectively, P=0.97). The increase in coronary blood flow during infusion of the peak dose of substance P was blunted at baseline in both the simvastatin (42+/-50%) and placebo (55+/-71%) groups, reflecting impaired endothelium-dependent dilation of coronary microvessels. After treatment, the flow increase was 82+/-81% in the simvastatin group and 63+/-53% in the placebo group (P=0.16).

CONCLUSIONS

Six months of cholesterol-lowering therapy has no significant effect on coronary endothelial vasomotor function in the study population of patients with coronary artery disease and mildly elevated cholesterol levels. These findings suggest that the effects of cholesterol lowering on endothelial function are more complex than previously thought.