A worker gives a blood sample for a cholesterol check in 2010 in the Bronx borough of New York. In a new trial, experimental drugs showed promise for lowering LDL cholesterol.(Photo: Chris Hondros, Getty Images)
An experimental class of drugs shows promise as a new way to lower the "bad" cholesterol that can lead to heart attacks.
A man-made antibody - similar to the immune system proteins that fight
infections - lowered LDL cholesterol by about 70% when combined with a
statin, according to a small, early trial published Wednesday in The New England Journal of Medicine.
Many heart disease experts are enthusiastic about the drugs, which will
be featured prominently at the American Heart Association's Scientific
Sessions that begin Saturday in Chicago.
"This is a new era of
novel therapies," says William Zoghbi, president of the American
College of Cardiology, who wasn't involved in the study.
The drop in cholesterol is "significant" and "much more than we usually see" with other types of drugs, Zoghbi says.
The preliminary study involved 92 patients whose cholesterol wasn't
improving with statins. In addition to taking atorvastatin pills, sold
as Lipitor, patients got injections of the new drugs, known as
monoclonal antibodies, every two weeks.
Significantly, the new
drugs haven't yet been shown to actually reduce heart attacks or deaths,
says cardiologist Cam Patterson, a professor at the University of North
Carolina-Chapel Hill. And while the drugs caused few side effects in
this study, doctors will need to conduct larger trials to show they're
really safe, he says.
The intravenous drugs could also prove to
help people who can't tolerate statins because of side effects, such as
muscle pain, says Robert Eckel, past president of the American Heart
Association, who wasn't involved in the new research.
"This a
promising step forward, especially for the most difficult patients to
treat," says Eckel, a professor at the University of Colorado Anschutz
Medical Campus.
Unlike statins, which prevent the liver from
making cholesterol, the new drugs target the process by which the liver
takes LDL out of circulation, Patterson says.
An enzyme called
PCSK9 prevents the body from getting rid of LDL, leaving it in the
bloodstream, where it can damage the arteries, he says. The new
antibodies block this enzyme.
The study was funded by the drugs'
developers, Sanofi and Regeneron Pharmaceuticals. Amgen and Pfizer are
also developing similar drugs, Patterson says.
If successful, the drugs could be a boost for the drug industry, now that statins are available generically, Patterson says.
Although man-made antibodies are widely used in cancer, they haven't
previously had success in heart disease. Man-made antibodies used in
cancer, such as Erbitux and Avastin, cost several thousand dollars a
month.
USA Today