Fix the Blind Spot in Drug Trials Says Every Major Obesity Group

Closed EyesIt is time to translate words into action and fix the blind spot in drug trials and labeling for people with obesity. Every major obesity group in the U.S. issued this united call to action on Tuesday. This includes the ASMBS, Obesity Action Coalition, Obesity Medicine, Obesity Society, and STOP Obesity Alliance. It comes as proceedings of a major FDA workshop on the subject were published in the Journal of Clinical Pharmacology. Obesity Action Coalition CEO and President Joe Nadglowski explained the need for action now:

Proceedings of a workshop organized in part by FDA scientists dealing with this subject were published this month. This tells us FDA is fully aware of the issue. Everyone deserves to know the drugs they use are safe and effective. The FDA and drug companies need to take action now.”

The call to action has two major components.

1. Close the Gaps

For drugs that people living with obesity will need for purposes other than treating obesity, FDA is not currently requiring they be tested for safety and effectiveness in people living with obesity. In fact, drug trials – either implicitly or explicitly – often exclude these people who represent 42% or more of the population that will need these drugs.

This is a huge mistake. Because, as proceedings of the FDA workshop show in great detail, obesity can have a big effect on how these drugs affect people.

2. Update Drug Labels Now

A number of prescription drugs are already on market with dosing instructions that are simply wrong for people with obesity. This is the legacy of the gap in drug testing and approval.

But the good news it that this is an easy problem to fix in many cases.

For example, brexpiprazole (Rexulti) has dosing instructions that will cause the drug not to work in many people with obesity. Scientists have identified dosing regimens that will work. But until FDA requires the company to put those directions in the package insert, most doctors won’t know and won’t prescribe the right dose.

Another example is posaconazole (Noxafil), which hangs around longer in the bodies of people with obesity. This creates a danger of drug interactions that can be life-threatening. Again, the fix is simple. Update the labeling for the drug so that doctors have this information.

Why Is This Happening?

Obesity Society President Elect Jamy Ard explains that excluding people with obesity from clinical trials is essentially a convenient shortcut for industry:

“Drug companies have an interest in reducing inter-subject variability, because in narrower subsections, drugs are more likely to perform as expected, thereby increasing the odds of getting approved. Unfortunately, variation in body size is easy to identify and as a result, drug companies often structure clinical trials to exclude people with obesity.”

Obesity Medicine Association President Angela Fitch says this is not OK:

“We must ensure drugs are safe and effective and labeled correctly for everyone for whom they are intended. Drug companies don’t get a pass on people with obesity.”

The action needed here is neither hard nor unreasonable. FDA and industry should fix this blind spot in drug trials and labeling. Now.

Click here for the joint statement and here for the OAC press release about it.

Closed Eyes, painting by Odilon Redon / WikiArt

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November x, 2023