Abbott Laboratories has received approval from US regulators for Simcor, the latest combination drug to be given the go-ahead as a treatment for cholesterol.

Simcor combines Abbott’s Niaspan (extended-release niacin) and simvastatin, the active ingredient in Merck & Co’s Zocor which came off-patent last year. It targets high-density lipoprotein or ‘good’ cholesterol, as well as low-density lipoprotein ‘bad’ cholesterol plus triglycerides in a single pill.

The green light from the US Food and Drug Administration is based on data from more than 640 patients which demonstrated that patients treated with Simcor enjoyed LDL reductions of 12% and 21% HDL increase compared to a 7% decrease in LDL and an 8% rise in HDL with simvastatin alone. Also the new drug combo reduced triglycerides by 27% compared to 15% with simvastatin alone.

Simcor was generally well tolerated but 6% of patients discontinued therapy due to facial flushing, the most commonly reported side effect of niacin-based therapies. Abbott noted that flushing can be minimised by taking aspirin or a non-steroidal anti-inflammatory drug 30 minutes prior to taking the medication at bedtime. Flushing may subside over several weeks of consistent Simcor, the firm added.

Abbott has predicted peak sales of the drug to be around $500 million a year and noted that results from its AIM-HIGH study, which is looking at the effects of niacin extended-release and simvastatin in reducing cardiovascular events in patients with existing heart disease, should be reported in 2011.

The timing of the Simcor approval could be beneficial for Abbott as it is hitting the market before Merck & Co’s potential competitor Cordaptive (extended-release niacin/laropiprant). Merck claims that its combo, which could possibly be approved in the second quarter, is effective in reducing flushing.