NIH Stops Clinical Trial After Niacin Fails to Decrease Heart Disease

The National Heart Lung and Blood Institute (NHLBI), a division of the National Institutes of Health (NIH), has stopped the AIM-HIGH clinical trial 18 months ahead of schedule because niacin did not show any benefit for heart disease patients.  The AIM-HIGH (Atherothrombosis Intervention in Metabolic Syndrome with Low HDL Cholesterol/High Triglyceride and Impact on Global Health Outcomes) study was designed to test if extended-release niacin could decrease heart disease in patients when given in combination with simvastatin.  Simvastatin is used to lower LDL-cholesterol, which is also known as the bad cholesterol.  Elevated LDL-cholesterol levels cause plaque to form inside arteries which can then lead to heart attack and stroke.  HDL-cholesterol, which is also known as the good cholesterol, is involved in moving cholesterol from arteries to the liver for further metabolism.  Thus, it is believed that high HDL-cholesterol levels could be protective against heart attack and stroke by eliminating or lowering overall cholesterol levels.  Previous observational studies and small clinical trials have shown that low HDL-cholesterol levels carry an increased risk of heart attack and stroke.  Thus, medications that raise HDL-cholesterol could theoretically protect against heart attack and stroke.  Niacin is one of many drugs that have been shown to raise HDL cholesterol levels, but it has not been studied in a large clinical trial until the AIM-HIGH study.  The AIM-HIGH study was a five year study that enrolled 3,414 participants with a history of heart disease and low levels of HDL cholesterol.  The participants were randomly assigned to take simvastatin, or to take simvastatin and extended release niacin.  The participants were followed for a total of 32 months while taking the medications before it was stopped prematurely.  The combination treatment of simvastatin and niacin did not reduce fatal or non-fatal heart attacks, strokes, or hospitalizations due to cardiovascular disease.  As a result, the decision to stop the clinical trial was made by the study’s independent data and safety monitoring board.  It was concluded by the monitoring board that “high-dose, extended-release niacin offered no benefits beyond [simvastatin] therapy alone in reducing cardiovascular-related complications in this trial”.  In addition, it was also concluded that “the AIM-HIGH findings do not support the trial’s hypothesis that, in the population studied; adding extended-release niacin to simvastatin in participants with well-controlled LDL cholesterol can provide additional clinical benefit.”  Of the participants that took niacin with simvastatin, there were 28 strokes (1.6%) versus 12 stokes (0.7%) for those participants that took only simvastatin.  The investigators added that “previous studies do not suggest that stroke is a potential complication of niacin, and it remains unclear whether this trend in AIM-HIGH arose by chance, was related to niacin administration or some other issue”.  The Food and Drug Administration issued a statement regarding the results and stated that patients taking niacin should not stop taking it until consulting with their physician, and the AIM-HIGH data was analyzed further.  The study was funded by the NHLBI and Abbott Laboratories, the maker of Niaspan which is a brand form of niacin.  Immediately after release of the report by the NHLBI, the price of Abbott shares dropped by more than 2 percent on the New York Stock Exchange.  Niaspan, a blockbuster drug for Abbott, generated $927 million in revenue for the year of 2010.  One out of seven Americans has a cholesterol disorder which has been shown to be a risk factor for heart disease and stroke.  Cardiovascular disease kills over 830,000 Americans each year.  As a result of the AIM-HIGH data, it appears that Niaspan may not continue to be a blockbuster drug for Abbott, and niacin may not play a major role in the prevention of heart attack and stroke for Americans.

Tagged as: AIM-HIGH clinical trial, cardiovascular disease, HDL cholesterol, heart attack, LDL cholesterol, niaspan, stroke