July 2, 2008

Experts Voice Concerns Over Diabetes Drug Testing Standards

Speaking before a U.S. advisory panel, Cleveland Clinic cardiologist Steven Nissen said higher standards of testing should be enforced to ensure that new proposed diabetes medicines do not damage patients' hearts.

"We have to rule out some level of harm prior to approval," Cleveland Clinic cardiologist Steven Nissen told the panel of experts that advises the Food and Drug Administration.

Some experts claim that stricter regulation may require longer clinical testing periods, which could slow the development of beneficial drugs.

Nissen's statement came in light of two new studies that found some drugs increased diabetics' risk of death.

Nissen co-authored an analysis last year that found patients who took GlaxoSmithKline's pill Avandia had a higher chance of having a heart attack.

Another government-funded study found diabetics given intensive therapy to lower blood sugar died at a higher rate than others who were allowed a higher blood sugar level. It said no one drug was to blame.

Currently, the FDA requires drug makers to prove only that the medicines control blood sugar.

The FDA, criticized for its oversight of Avandia and other drugs, is asking the panel of outside experts how much data to demand on cardiovascular effects for new and already approved diabetes drugs.

Recommendations are expected from the panel on Wednesday. The agency usually follows its panels' advice.

Experts say that blood-sugar control among diabetics helps reduce health risks such as damage to vital organs. However, no conclusive evidence exists that any diabetes drug reduces heart disease, the top killer of diabetics, FDA officials said.

Hylton Joffe, lead medical officer in the FDA's diabetes drug group, said the agency will request a long-term trial on heart risks if mid- and late-stage testing raises concern.

However, some experts still debate the need for all diabetes drugs to undergo testing to prove they actually benefit the heart rather than harm it, a requirement which would "set a very high hurdle that would affect the availability of new drugs," Joffe said.

Nissen said he hopes the FDA will make require companies to collect enough data to rule out a certain level of cardiac harm before approval. The FDA also should mandate that companies start a long-term study of heart-related effects before they can sell a new medicine, he said.

"We can still get drugs to patients in a speedy fashion," he said.

Diabetes affects about 24 million Americans. Type 2 diabetes, the most common form, is linked to obesity, poor diet and lack of exercise.

U.S. sales of leading diabetes drugs exceeded $6 billion in 2007, according to healthcare information company IMS Health.

Top drugs include Glaxo's Avandia and Takeda Pharmaceutical Co's rival Actos.

Glaxo has said Avandia's safety is comparable to similar pills. The company agreed to add a strong warning, however, that the drug might increase heart attack risk with a note that the data is inconclusive. Studies of cardiac effects are continuing.


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