Chelation therapy trial continued despite risks

With $30 million of taxpayer money, researchers set out to conduct one of the largest studies ever of an alternative medical treatment. The question: Does intravenous chelation therapy to expel metals from the body improve symptoms of coronary artery disease?

The Trial to Assess Chelation Therapy was designed to test a remedy that has been used by tens of thousands of Americans. TACT had the support of a powerful congressman and funding from two branches of the National Institutes of Health. One of them, the National Center for Complementary and Alternative Medicine, was leading the project.

But the trial was marred by problems from the start.

The scientific foundation for chelation was weak, based on decades-old ideas about plaque in the arteries that have never been proved. The treatment was so out of step with mainstream medicine that it was difficult to recruit patients willing to take part. Researchers made confusing statements about the drug being tested, giving volunteers the false impression that it was safer than it was. Several doctors involved in the trial ran into disciplinary problems, and two were convicted of crimes.

Perhaps most troubling: The drug, edetate disodium, turned out to be so risky that theU.S. Food and Drug Administrationwithdrew its approval. Yet the study was not halted, and the volunteers were not immediately told.

The NIH "is the nation's premier medical research facility," says Liz Woeckner, president of Circare, a Philadelphia-based nonprofit that advocates on behalf of people enrolled in clinical trials. "For them to conduct a trial that is unethical and unscientific — and to continue to conduct it? It is just mind-boggling."

Dr. Josephine Briggs, head of NCCAM since 2008, declined to discuss the study in detail because it is now overseen by the National Heart, Lung and Blood Institute, which is also part of the NIH. But Briggs says that such research is difficult to conduct because "physicians are highly polarized in what they believe."

Dr. Susan Shurin, acting director of the NHLBI, said in a written statement that a well-designed, sufficiently large clinical trial of chelation therapy was needed. "The lack of compelling evidence to support a widely practiced therapy is an argument FOR doing a randomized trial, not against it," she wrote.

TACT's principal investigator, Dr. Gervasio Lamas, said in a written statement that researchers are committed to ensuring the highest level of patient safety.

"We are serious scientists trying to provide needed evidence to define whether chelation therapy for coronary heart disease should be part of the standard clinical armamentarium, or whether the risks of chelation outweigh any possible benefit," wrote the cardiologist, who is chairman of medicine at Mount Sinai Medical Center in Miami Beach, Fla.

Decalcifying theory

In the 1950s, doctors hypothesized that edetate disodium could strip calcium from the plaques that clog arteries, helping break those plaques down. It would be like Drano for blood vessels, they figured.

In fact, edetate disodium can rapidly extract calcium from the entire body, which can cause an electrolyte imbalance and interfere with the beating of the heart, sometimes fatally.

In a document submitted as part of a grant application, Lamas acknowledged there was "little data to support the decalcifying hypothesis." What's more, three randomized, double-blind clinical trials found no meaningful difference between chelation therapy and a placebo.

With scant 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 Rep. Dan Burton (R-Ind.). An advocate of alternative medicine, Burton wanted to know why NIH wasn't spending more of its taxpayer dollars studying such treatments. So in 1999, he brought the director of the National Heart, Lung, and Blood Institute before a congressional committee and pressed him to explain why the institute had not yet conducted a study like TACT.

Burton left NIH officials with an unambiguous message: "We are going to be hauling them before this committee on a regular basis — they will get sick of seeing my face before this is over — to make sure that we are not blocking something that is going to save lives."

TACT was underway a few years later.

More than 2,300 heart attack survivors older than 50 would be randomly assigned to one of four groups, according to the study protocol. Some would receive 40 infusions of a chelation solution plus either high or low doses of supplements. Others would receive 40 infusions of a placebo with either high or low doses of supplements. The study would be double-blinded, meaning neither volunteers nor researchers would know who got the treatment and who got the placebo.

Among the collaborators were many fine doctors who enrolled volunteers and ran study sites out of their own clinics. But 13 of them have run afoul of state medical boards or health departments for actions unrelated to the chelation study. Two physicians had their medical licenses revoked. Two others paid fines for placing misleading ads about the benefits of chelation therapy. One was issued two administrative complaints for allegedly running a clinic with unsanitary conditions linked to a hepatitis C outbreak.