At the beginning of last month we announced that the new
weight loss pill named Belviq©, from Arena
Pharmaceuticals, was going to be able to be prescribed soon to obese and
overweight patients in the United States. Since then, many criticisms have
accompanied its debut. One in particular was made by Consumer Reports.
The article gives two main reasons as to why Consumer
Reports do not recommend taking the pill. First of all, they claim that studies
show that patients who take it for a year are expected to lose only a slight
percentage of their body weight (from 3 to 3.7%). Second, the side effects
might be quite severe.
Another article, published in the Los Angeles Times, also
heavily criticises the drug, saying that patients who decide to take it must
take it for their whole life in order to keep the weight off. They also mention
that long-term side effects are not predictable and that quick-fix pills are simply
not effective at resolving a complex problem such as obesity.
While some of the criticisms may be valid, it is really up
the doctor and patient to decide what is appropriate. It is true that some
patients do not lose very much weight – this is the case with other weight loss
medications as well. The low responders (as we call them) can usually be
identified early (within a couple of months) and they should probably stop
being prescribed further courses as the risk of side effects may outweigh any
potential benefit from the marginal weight loss.
We have to concede that the average weight loss is not impressive
and it probably should only continue being prescribed on a patient by patient
basis if they are losing reasonable levels of weight. 3% over the course of 12
months is really not sufficient to justify continuing prescribing.
Belviq contains Lorcaserin as the active ingredient. The
application for a license to have Lorcaserin prescribed in the EU was recently
withdrawn as Arena Pharmaceuticals was not going to be in a position to answer
all of the outstanding questions with the European Medicines Agency. We would
expect a further application to be made in due course.