A new class of experimental medicines can dramatically lower cholesterol, raising hopes of a fresh option for people who cannot tolerate or do not get enough help from statins.
The first large studies of the drugs were presented over the weekend at an American College of Cardiology conference in Washington, where they generated a lot of interest.
Several companies are developing these potential treatments, called monoclonal antibodies. Three studies of Amgen’s version, called evolocumab, found it reduced low-density lipoprotein (LDL) by 55-66% from baseline levels compared with others who took a placebo.
Evolocumab is an investigational fully human monoclonal antibody that inhibits proprotein convertase subtilisin/kexin type 9 (PCSK9), a protein that reduces the liver’s ability to remove LDL-C from the blood
However, given the strong track-record of statins, researchers are also seeking evidence that the new class will lead to fewer heart attacks and deaths, as well as simply lowering cholesterol.
New studies are under way to test this, but Amgen said it would seek US approval for its drug this year based on cholesterol-lowering alone.
Hopes are high that the new drug and others like it will do better than previous treatments touted as successors to statins, such as ezetimibe (Zetia or Ezetrol). Use of ezetimibe has declined since 2008, when research showed it failed to help prevent heart attacks even though it cut cholesterol.
Nearly all current cholesterol medicines − fibrates, niacin and top-selling statins − are decades old. Statins curb cholesterol production, while ezetimibe, which came out about a decade ago, helps block the absorption of cholesterol from the intestine.
The new drugs block PCSK9, a substance that interferes with the liver’s ability to remove cholesterol from the blood.
They do have drawbacks, however. For example, the new drugs are proteins which tend to be very expensive to make. They must also be given as shots every two weeks or once a month.
Patients can give the shots to themselves with a pen-like device. The companies developing the new medicines have not said what they might cost.
This compares to statins that are easy to take pills and many of which are now generic and therefore very cheap.
Dr Michael Koren, from the Jacksonville Centre for Clinical Research in Florida, helped lead two of the studies on the new drugs.
“We were very, very pleased” about how well patients accepted the shots, and if they offer better results, especially for those with inherited conditions, “people will accept it,” he said.
The three Amgen studies − MENDEL-2, DESCARTES and RUTHERFORD-2 − involved about 2,000 patients in all and were presented at the conference on Saturday. A further two studies – GAUSS-2 and LAPLACE-2 – were also presented on the drug on Sunday.
They were tested in people with high cholesterol not taking other medicines, as a long-term (one-year) treatment in people already taking various medications and in combination with statins and other drugs in people with an inherited cholesterol disorder.
In general, side-effect rates were about the same for evolocumab versus placebo or ezetimibe. In some studies, muscle aches, nausea and a few other problems were a little higher with the experimental drug.