Niacin extended-release/lovastatin: Combination therapy for lipid disorders

The new combination of niacin extended-release (ER) and lovastatin (Advicor™, Kos pharmaceuticals), is a powerful lipid modifying agent and takes advantage of the different mechanisms of action of its two components. Niacin decreases hepatic atherogenic apolipoprotein (apo) B production whereas lovastatin increases apoB removal. Whereas niacin potently increases high density lipoprotein (HDL) levels by decreasing hepatic removal of antiatherogenic apoA-I particles, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors ('statins') appear to increase production of apoA-I. Although there is no outcome data with this combination product, each component has been independently associated with a reduction of cardiovascular event risk by ∼ 25 - 35%. The results of a long-term trial in 814 patients, where > 600 had been treated for 6 months and > 200 for 1 year, found reductions of 45 and 42% in low density lipoprotein cholesterol and triglycerides, respectively, at the maximum dose (niacin ER 2000 mg/lovastatin 40 mg). HDL cholesterol increased by 41%. In addition, the combination decreased lipoprotein (a) by 25% and C-reactive protein by 24%. The niacin ER/lovastatin combination was generally well-tolerated. Flushing was the most common side effect, with ∼ 10% of patients intolerant to niacin ER/lovastatin. Hepatotoxicity in this study was 0.5% and myopathy did not occur. Recent studies indicate that niacin can be used safely in diabetic patients who have good glucose control (HbA < 9%). Once-daily niacin ER/lovastatin exhibits potent synergistic actions on multiple lipid risk factors and represents an effective new agent in the clinical management of dyslipidaemia. Outcome studies are needed to evaluate if combination therapy would result in additive effects on morbidity and mortality.