A Follow Up Note on Qnexa and Obesity

First, in response to a few questions that folllowed my Qnexa post (also the associated post on my Psychology Today blog).

On Feb 22 the FDA Advisory Committee voted to recommend approval - which usually signals that approval will be granted; but the final decision is to be made mid April. In other words, as of now, Qnexa does not have FDA approval for obesity.

But these questions about approval stirred my curiosity about the level of buzz Qnexa has generated.

How can one gauge that?

Well here is what I did.

I decided to use a reputable medical meta-search engine and compare the number of hits for Qnexa with the number of hits for some other new medication for a different indication.

I've chosen Trip Database as my meta-search engine. Trip Database not only provides a very solid search tool but also presents the search results in a format that makes it easy to differentiate between the different types of  retrieved data (eg, original research, guidelines, textbooks or news). I then compared the search results for "Qnexa and obesity" with the search results for "asenapine and schizophrenia".

Why choose asenapine? Asenapine is neuroleptic that got FDA approval for the treatment of schizophrenia back in 2009. As such it's still a relatively new medication (for a fair comparison with the very new Qnexa) and at the same time it's been around for long enough to generate some news (or so you'd think).

Why choose schizophrenia? As, similar to obesity, it represents another major public health issue. In case you don't know the most recent global burden of disease data form the World Health Organization place schizophrenia at #9 on the top 20 causes of disability word-wide. For comparision sake I should also mention that obesity, while a major health issue in the US, doesn't even make it on the same world wide top 20 list.

What are the results?

In a couple of my prior posts I used the "asenapine and schizophrenia" example to discuss on how to search for the best evidence (Tripping for Evidence Part 1 and Part 2). So last night I just re-run the same search for "schizophrenia and asenapinelast" on Trip Database and I got 20 hits (search results as of March 12, 2012). The "Qnexa and obesity" search on the same site returned 32 hits total.

So we got thirty percent more hits (ie, publications) for a drug that is yet to get FDA approval.

But it gets even more interesting than this: from the 20 asenapine results about 15% (N=3) were news reports. For Qnexa 100% (N=32) of the hits are news results.

Granted, this are proxi measures at best. However, as a indirect measure of the buzz out there when it comes to different public health issues, in this case, schizophrenia and obesity, the results are pretty telling.

And the story they tell is that as a society we seems to be overinterested in issues related to weight and body image. That in itself might be part of the problem.

© Copyright Adrian Preda, M.D.

Tripping for Evidence - Part 1

Take a Trip!

You search Trip Database for "asenapine and schizophrenia".

One of the nice things about Trip is its color-coding of what it finds based on the quality of the evidence.

Green is best. This includes evidence based synopses, guidelines and systematic reviews. Why is this best? Because people who know what they do already reviewed the available evidence, graded it and summarized it - all in all, less work for you!

Blue is for original research, i.e. research that you need to directly review and asses according to "best evidence" criteria.

Red and brown is for textbook based evidence (otherwise known as background evidence), news etc. - evidence that maybe informative but it's harder to asses in terms of validity and bias.

You would hope that you will find evidence clustering towards blue. In this instance though Trip doesn't find any "best evidence". You find only 3 articles, all original research. From those, there is only one clinical trial comparing asenapine (Saphris) with risperidone (Risperdal) in schizophrenia (Potkin 2007).

Good try but you need to move to step 2: SUMSearch.

N.B. In the future, if you want to try your own "trips" from this blog, you can go under the "search this" box and simply click on Trip Database.

For Part 2 of Tripping for Evidence please go HERE.

References:

Potkin SG, Cohen M, Panagides J. Efficacy and tolerability of asenapine in acute schizophrenia: a placebo- and risperidone-controlled trial. J Clin Psychiatry. 2007 Oct;68(10):1492-500.

© Copyright Adrian Preda, M.D.