Troubled study at heart of therapy debate
Disciplined doctors, potentially deadly drug marred study of questionable treatment that cost taxpayers $30 million
Dr. Rajiv Chandra, standing, with three of his patients that received chelation therapy. (Jacob Langston/Orlando Sentinel)
Problems with TACT start with the most basic of all: There was little scientific reason to believe the study drug, edetate disodium, could help treat coronary artery disease.
In fact, far from helping, edetate disodium can rapidly strip calcium from the body, which can cause an electrolyte imbalance and interfere with the beating of the heart, sometimes fatally.
In the 1950s, doctors hypothesized that the drug could yank calcium from the plaques that clog arteries, helping break them down, like Drano for blood vessels. The therapy has been promoted over the years in books like "Bypassing Bypass: The New Technique of Chelation Therapy" and on practitioners' websites.
But in a document submitted as part of the grant application, Lamas acknowledged there was "little data to support the decalcifying hypothesis." He listed six other possible explanations for how chelation therapy could help, but none had been proved.
Scientists say it's fine to study a potential treatment without knowing exactly how it works — but there needs to be compelling evidence to suggest that it does work.
Chelation to treat coronary artery disease didn't have that either. Three randomized, double-blind clinical trials found no meaningful difference between chelation therapy and a placebo.
Dr. Edzard Ernst, a retired professor of complementary and alternative medicine at University of Exeter, summed up the evidence in a 2000 review published in the American Heart Journal. "The most striking finding is the almost total lack of convincing evidence for efficacy," Ernst wrote. "Given the potential of chelation therapy to cause severe adverse effects, this treatment should now be considered obsolete."
Lamas wrote in an email that the study had a plausible hypothesis that deserved to be tested. "TACT was supported by Congress, reviewed by multiple peer-review committees and approved," he wrote.
Dr. Clyde W. Yancy, chief of the cardiology division at the Northwestern University Feinberg School of Medicine, agreed with Lamas. "It's time to either prove this to be a reasonable treatment or put it to rest," Yancy wrote in an email.
Yet this is a question cardiac researchers were not clamoring to answer. Over a period of 30 years, the NIH's National Heart, Lung, and Blood Institute received just three chelation-related research grant applications amid tens of thousands, according to congressional testimony. They were not funded.
"If the science is invalid," said Woeckner, who advocates for the rights of clinical trial patients, "it is unethical to expose human beings to any risk whatsoever."
With scant compelling evidence that chelation therapy might be safe and effective for coronary artery disease, why did the government spend $30 million of taxpayer money studying it?
The answer begins with a powerful politician.
In 1999, Rep. Dan Burton, R-Ind., held a congressional hearing titled "Cardiovascular Disease: Is the Government Doing More Harm Than Good? EDTA Chelation Therapy."
An advocate of alternative medicine, Burton wanted to know why NIH wasn't spending more of its taxpayer dollars studying such treatments.
He brought the director of the National Heart, Lung, and Blood Institute, Dr. Claude Lenfant, before the committee and pressed him to explain why the institute had not yet studied chelation therapy for coronary artery disease.
Then he asked proponents of chelation therapy to talk about how effective it was and how the therapy had not been given a fair shake.