Niacin Outperforms Ezetimibe as Add-On to Statin Therapy

Niacin is more effective in slowing atherosclerosis and reducing heart disease risks than ezetimibe, it was noted.

The findings from the Effect of Extended-Release Niacin or Ezetimibe Added to Chronic Statin Therapy on Carotid Intima Media Thickness (ARBITER 6-HALTS) trial were presented at the AHA meeting in Orlando. Allen Taylor, MD, Uniformed Services University of the Health Sciences and Walter Reed Army Medical Center, Washington, DC, reported the results.

Add-on treatment with niacin 2 g daily produced statistically significant reductions in carotid intima-media thickness (CIMT) when compared with ezetimibe (P <= .001 for all comparisons).

Dr. Taylor and colleagues noted that, while statins reduce low-density lipoprotein cholesterol (LDL-C) and clinical events, the residual cardiovascular risk associated with statin monotherapy may be intensified with combination therapy. The purpose of this study was to compare 2 combination therapies for 14 months, using carotid intima thickness as the primary endpoint.

The trial was terminated early for efficacy, however, based upon a prespecified analysis after 208 patients had completed the trial.

All subjects had coronary heart disease or risk equivalents. They were 80% male, with a mean age of 65 (+/- 11 years) and all had been on statins for a mean of 6 years (+/- 5 years). Mean LDL-C at enrolment was 82.1 (+/- 23.1) mg/dL, and mean high-density lipoprotein cholesterol (HDL-C) was 42.4 (+/- 8.5) mg/dL.

All subjects were on a consistent dose of statin monotherapy and had a lipid panel within 3 months demonstrating LDL-C of <100 mg/dL and HDL-C of <50 mg/dL for men and <55 mg/dL for women.

For the primary endpoint of CIMT, subjects in the niacin arm achieved a greater change over 14 months (P = .003), showing significant regression of both mean CIMT (P = .001) and maximal CIMT (P <= .001).

Paradoxically, among ezetimibe subjects, reductions of LDL-C with ezetimibe were associated significantly with CIMT progression (P < .001).

Incidence of major cardiovascular events was lower for subjects receiving niacin versus subjects receiving ezetimibe (1.3% vs 5.8%; P = .029).

Dr. Taylor concluded, "ARBITER 6-HALTS provides a clear and undeniable statement on the superior clinical effectiveness of niacin over ezetimibe."

The AHA-appointed commentator on the study, John Kastelein, MD, PhD, Academic Medical Center, University of Amsterdam, Netherlands, was less enthusiastic. While supporting the accuracy of the findings, he noted that the study was small and that the use of niacin has significant practical, clinical problems. "Because of the side effects of niacin -- notably flushing -- virtually no one in Europe uses niacin. This is a real practical problem."

Mariel Jessup, MD, University of Pennsylvania, Philadelphia,  and chairperson of the program committee for the Annual Scientific Sessions, added that her objections to Dr. Taylor's presentation were not over the findings but over the strength of the conclusions. "I think people are distressed in particular about the post hoc analysis that looked at the relationship between ezetemibe's lowering of LDL and the actual increase in intimal wall thickness. They think that was an unwise thing to do in a small trial."

Funding for this study was provided by Abbott.

[Presentation title: ARBITER 6-HALTS: The Effect of Extended-release Niacin or Ezetimibe Added to Chronic Statin Therapy on Carotid Intima Media Thickness. Abstract 09-LBCT-19941-AHA]

Taylor AJ, Villines TC, Stanek EJ, et al. Extended-release niacin or ezetimibe and carotid intima-media thickness. N Engl J Med 2009;Nov 15:[Epub ahead of print].