Waiting for Gateau: Will a New Weight Loss Drug Let Us Eat Again?

by Barbara Berkeley, MD

This week saw the approval of a new weight loss medication by the FDA.  It is the first time in 13 years that  a drug for obesity has been green-lighted.  Lorcaserin (lor cah SAYR' in), which will be marketed as "Belviq" (which sounds like birth control pill or a hearing aid to me), clawed its way to an FDA go ahead after initial rejection on safety grounds.  The door may now be open for other hopefuls like Contrave and Qnexa.  Investors certainly hope so, because with obesity dogging one in three Amercans, weight loss drugs can explode out of the gate with a consumer market like no other.  It wouldn't be a stretch to imagine that a reasonably effective weight loss pill could become the best selling drug of all time.

An understanding of this dynamic is what has led the FDA to be circumspect in its consideration of new meds.  It has already been necessary to unring the bell with Phen-Fen and Meridia and the huge potential distribution of any new anti-fat pill means that millions are immediately exposed to any unknown risks.  In fact, the FDA has asked Arena Pharmaceuticals to conduct a number of studies on heart and stroke risk after the drug is in use.  Those who take these drugs should be aware that they are essentially part of a huge, ongoing clinical trial.

Having said this, there is a risk to any new drug.  As we know so well, medications that seemed safe in pre-market testing and later enjoy years of use can turn out to be bad actors.  This was true of the anti-inflammatory Vioxx and the widely prescribed diabetes drug Avandia, both of which were pulled from the market due to heart risks. 

But let's get to the heart of the matter shall we?  Can diet drugs work and should we take them?

Like most questions that involve obesity, the answer is complicated.  

If we assume that a safe drug could be developed, we are still left with a central problem: treatment with medication for obesity is based on a concept that (in my opinion)  is wrong.  The principle? That weight loss itself is the endpoint.  Weight loss interventions that target only the acute state (weighing too much) are useless.  Obesity represents a metabolic dysfunction or dysregulation that occurs when a susceptible person eats the modern diet.  This dysfunction is not eliminated or even made better by loss of weight.  The formerly heavy personfeels better, but this state is temporary since the problem remains and quickly reasserts itself.  Thus, the need for books, blogs, and an ever-increasing focus on weight maintenance.  This seems obvious to me, and probably to you as well (since you are reading a maintenance blog), but it is not obvious to anyone else. 

Weight maintenance, and not weight loss, remains the true problem for our country.  Yet we continue to devote millions to the development of drugs that promote weight loss.  It's nonsensical.  Even treatments that last beyond the initial loss like surgery, lose effectiveness when the ability to eat the modern diet returns. 

You will note that Belviq, like other weight drugs before it, will carry the restriction that it be used only in those who have a BMI of greater than 30 or of 27 with co-morbid conditions.  This means that it cannot be used in those who successfully lose weight.  If the drug is the primary intervention, the reward for exposing oneself to medication risk is very likely to be regain. 

Drugs are not meant to work as social agents which block the consequences of behaviors that are harmful to us.  We could, for example, try to develop drugs that mitigate the harm of smoking so that we could keep on puffing away if we wanted to.  But no one suggests that.  There are so many potential harms to smoking that a single drug that protects us would be unlikely.  More to the point, it seems senseless to try to make a bad habit healthier.   We can extend this to weight loss medications.  No single drug is likely to protect us from the consequences of eating a diet to which we are intolerant.  Yet this is what we all seem to be seeking: a pill that both lets us have our cake and stop worrying about it. 

Belviq is a minimally useful agent for weight loss if studies prove to be correct.  It's not going to be the magic bullet.  Yet it might have been a useful drug for solidifying a year or two of weight maintenance, perhaps cutting appetite enough to allow maintainers to establish new habits during a treatment phase.  Unfortunately, the drug is already being heralded as yet another way to shrink without thinking.  

As if that were enough.