Drug to prevent heart attack

A new drug can prevent heart attacks and strokes by radically lowering cholesterol levels, scientists have found. The first tests of the drug, known as evolocumab, found that it significantly reduced the chances that a high-risk patient would have a heart attack or stroke after exhausting all other options.

The results of a large international trial on 27,000 patients found that those who took the drug saw their bad cholesterol levels fall by about 60 per cent on average.

About 80 per cent of the patients involved in the study had already had a heart attack and the rest had a stroke or pain in their legs and feet from narrowed arteries and were taking statins (drugs used to reduce bad cholesterol — low-density lipoprotein cholesterol — in the blood). Patients were eligible for participation in the trial if they were aged between 40 and 85 and had clinical evidence of a heart condition.

A total of 13,784 patients were given the drug and the other 13,780, a placebo. All patients continued taking their statins but half were told to inject themselves with evolocumab, also known as Repatha, and the rest were given a placebo.

Results from the two-year study (from February 2013 to June 2015) showed that those who took evolocumab injections saw bad cholesterol levels in their blood fall even further and were also less likely to suffer a heart attack or stroke than those who took the placebo.

LEADING CAUSE OF DEATH

The study cost about $1 billion (Sh103.1 billion), which was paid for by the maker of the drug, Amgen.

The results were published in The New England Journal of Medicine and presented at the annual meeting of the American College of Cardiology. The drug can make cholesterol reduce to levels almost never seen naturally in adults, or even in people taking cholesterol-lowering drugs.

“We have seen cholesterol levels lower than we have ever seen before in the practice of medicine,” said Prof Peter Sever, from Imperial College London. Prof Sever added: “This is one of the most important trials of cholesterol lowering since the first statin trial, published 20 years ago. Our results suggest this new, extremely potent class of drug can cut cholesterol dramatically, which could provide great benefit to a lot of people at risk of heart disease and stroke.”

Cardiovascular diseases are the leading cause of death globally with an estimated 17.5 million people dying in 2012, representing 31 per cent of all global deaths. Of these deaths, an estimated 7.4 million were due to coronary heart disease and 6.7 million were due to stroke. Bad cholesterol clogs up blood vessels, which fatally starves the heart or brain of oxygen.

To prevent this from happening, millions of people take drugs called statins to reduce the amount of bad cholesterol in their vessels. “While statins have had a significant impact in reducing the risk of heart disease for millions of people, they are not tolerated by everyone and only reduce cholesterol by a certain amount,” said Prof Sir Nilesh Samani, medical director at the British Heart Foundation.

From the study, patients had 15 per cent reduction in the combined risk of having a heart attack or stroke or dying from cardiovascular disease, being hospitalised for worsening chest pain or having a stent inserted to open a blocked artery (1,344 evolocumab patients versus 1,563 placebo patients).

Participants in the study, who used the drug for more than two years, were 20 per cent less likely to die from heart disease, have a heart attack or suffer a stroke (816 patients taking evolocumab had one of those outcomes compared to 1,013 taking the placebo). The absolute reduction in the risk of a heart attack or stroke was 1.3 per cent at two years, and two per cent at three years.

Although it is too soon to know if the drug is saving lives, the study showed that one heart attack or stroke was prevented for every 74 patients taking the drug in the trial. 

Evolocumab changes the way the liver works to also cut bad cholesterol. It is an antibody, just like the weapons used by the immune system to fight infection. However, it has been designed to target a protein in the liver known as PCSK9. The antibody is given by injection into the skin every two to four weeks.