A new class of drug cut the risk of repeat heart attacks by a quarter in a trial that opens another front in the fight against one of Britain’s biggest killers.

Medicine targeting the body’s natural inflammatory response to illness has been shown to protect heart patients from further life-threatening complications.

Doctors said that the “incredibly important” and long-awaited results would save lives by opening a new era in heart disease treatment that gave extra protection on top of existing care.

Almost 200,000 Britons a year suffer a heart attack and they are given medicines such as cholesterol-lowering statins and blood-thinning drugs to protect them. However, a quarter suffer a second heart attack within five years.

Scientists have believed for years that the inflammation that forms part of the body’s immune response to an attack may increase this risk, by breaking up fatty plaques in a way that makes them more likely to block arteries, for example.

Until now, however, it had never been shown that reducing inflammation could prevent heart attacks. Canakinumab costs £40,000 per patient per year as an arthritis treatment.

While cost could delay widespread use of the medicine alongside statins — which have an annual cost of only £20 per patient — experts said the proof of principle in yesterday’s results could open the door to development of a completely new class of heart drugs.

Paul Ridker, of Brigham and Women’s Hospital at Harvard University, who led the trial, said: “For the first time we’ve been able to show definitively that lowering inflammation independent of cholesterol reduces cardiovascular risk.

“This has far-reaching implications. It tells us that by leveraging an entirely new way to treat patients — targeting inflammation — we may be able to improve outcomes significantly.”

Dr Ridker recruited 10,000 patients who had had a heart attack and were being treated with statins and other medicine. They were given either a placebo or doses of canakinumab.

Those given three-monthly injections of 150mg of canakinumab were 15 per cent less likely to suffer heart problems, including fatal heart attacks and strokes, in the next four years. Those who had the biggest reduction in inflammation cut their risk of such problems by 27 per cent.

Heart attacks were down by 24 per cent. This meant that each year 1.9 per cent of patients on the drug had a heart attack, compared with 2.4 per cent in the control group.

Canakinumab patients were also a third less likely to need surgery, according to results presented at the European Society of Cardiology Congress and published in the New England Journal of Medicine.

Dr Ridker said: “I’ve seen three broad eras of preventative cardiology. In the first we recognised the importance of diet, exercise and smoking cessation. In the second we saw the tremendous value of lipid-lowering drugs such as statins. Now we’re cracking the door open on the third era.”

Trials are already looking at much cheaper drugs that have similar effects.

Analysis
Doctors already have several ways to protect the heart: medicines that reduce blood pressure, prevent clots or cut cholesterol.

The long-term significance of yesterday’s findings is that they can now do something else entirely — reduce inflammation.

Canakinumab is already being talked of as a blockbuster medicine but even if it does live up to the hype, the more important hope is that it paves a way for others that do the same thing.

There are two key obstacles: First, cost. Novartis is likely to cut the £40,000 cost if it is licensed as a heart treatment but it would have to be a dramatic discount to compare with generic statins at £20 a year. Second, side-effects. Other anti-inflammatories have been implicated in fatal bleeding and more investigation will be needed.