As a culture we don’t plan for a sudden halt in scientific advancements. Our tendency is to expect progress to be rapid and continuous. My prediction is that in certain areas of medical science we are likely to see not only a halt in progress but a slipping backward. In particular, the realm of medical weight management is in complete disarray at this time. Two new drugs designed to induce weight loss have been shot down by the FDA in the last few months. The first is Qnexa, developed by Vivus Inc. Interestingly, Qnexa combines two drugs already approved for use in the U.S. One of the drugs is phentermine which is a medication used for decades as an appetite suppressant. The other is a common drug used to treat seizures with the brand name Topamax (topiramate) which also induces weight loss. The drug performed admirably in clinical trials with most participants losing over 10% of body mass. The FDA cited excessive risks of the drug in its statement of rejection. One wonders why the drugs are still being marketed separately if they are so dangerous.

The latest drug to be rejected by the FDA is Lorgess (lorcaserin), developed by Arena Pharmaceuticals. This drug, not as effective as Qnexa, produced 5% body mass loss in about half of participants in clinical trials. Lab animals showed a tendency to develop breast tumors when exposed to the medication, adding to the FDA’s decision to reject the drug application based on safety concerns.

I am a strong advocate of drug safety and regulation. On the other hand we know obesity, and with it Type 2 diabetes, is epidemic in the U.S. I regard weight loss as the “holy grail” when treating type 2 diabetes and yet it is the most difficult goal to achieve. Any drug which could assist in weight loss is highly desirable in the treatment of Type 2 diabetes. Not only does blood sugar improve with weight loss but also blood pressure and cholesterol readings show declines. All three of these parameters are known to be prime contributors to the main cause of death in diabetics, cardiovascular disease.

It has already been 10 years since the last drug was approved specifically for a weight loss indication. The failure of these two latest medications to achieve approval is certain to cause the pharmaceutical industry to severely curtail if not abandon further investment in this type of drug development.

Why is the FDA so reluctant to approve a weight loss pill? This is a complex issue but requires an answer. A new weight loss inducing medication is certain to be highly anticipated and widely prescribed. Therefore, from the very first day of approval the FDA must take responsibility for the well being of millions of people who are likely to take the medication. We are a society which demands our medications deliver miraculous cures with no side-effects. If someone perceives they have been injured by a medication our legal system is primed to unleash brutal retribution on everyone remotely involved in the approval process. Abuse and injury with a medication designed to cause weight loss is almost a certainty. This is a no-win situation for the administration of the FDA.
I predict it will be at least another 10 years before a medication for weight loss is approved by the FDA. Unless there is a change in the climate of litigation in this country it will take longer than that. In the meantime the only new developments in weight loss drugs will be the result of exploiting appetite suppressant effects which are the “side-effect” of medications approved for other purposes.

Gary Pepper, M.D.
Editor-in-Chief, Metabolism.com