The hunt for new heart drugs is losing momentum as resources are switched to other areas, notably cancer research, where investors get a better bang for their buck.
Cardiologists fear the fight against heart disease could stall as a result, following major advances in recent decades marked by the advent of drugs to lower cholesterol and blood pressure and to prevent dangerous blood clots.
The disparity between advances in cancer and heart medicines is already stark. Since the beginning of 2012, 17 cancer drugs been approved by the Food and Drug Administration, compared with just three for heart disease.
"There is a clear move of R&D from cardiovascular to cancer and other areas," said Michel Komajda, a heart specialist at Pitie-Salpetriere Hospital in Paris and a former president of the European Society of Cardiology (ESC).
Like many of his colleagues gathered at the annual ESC congress this week in Amsterdam, Komajda is worried.
Despite the giant drugmakers' stand touting heart medicines at this week's meeting of some 30,000 doctors, investment in cardiovascular medicine is ebbing—prompting calls for an urgent rebalancing of research priorities.
"There is a view among some that because we have already made a lot of progress in cardiovascular medicine then maybe it doesn't make sense to invest any more," Komajda said. "But there are still some big areas where we need progress, including acute heart failure, which is a growing problem because of an aging population."
To some extent, cardiology is a victim of its own success. By any measure, the global war on heart disease to date has been successful, because of better drugs as well as prevention strategies such as anti-smoking campaigns.
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In Europe, the death rate from cardiovascular disease has been cut in half over the past 30 years, while the risk of dying within 30 days of a heart attack has been halved in just 20 years.
No. 1 killer
Yet cardiovascular disease remains the No. 1 killer worldwide, and doctors fear a renewed epidemic of problems in 20 to 30 years time as a new generation of overweight and obese youngsters reaches middle age.
"It's a huge concern," said Patrick O'Gara of Boston's Brigham and Women's Hospital, who is also president-elect of the American College of Cardiology. "We need to replenish the fuel that drives the engine."
Many patients remain at risk of clogged arteries, despite taking cholesterol-lowering statins, while heart failure—where the heart fails to pump blood adequately—remains a deadly disease that has seen little progress in treatment in 40 years.
Developing new heart drugs takes particularly heavy spending, with uncertain returns. Further, patent expirations mean many previously profitable heart drugs are now available as cheap generics, reducing drugmakers' revenue.