Weight Reduction Drugs: Slow Progression and Innovation

There have been a total of seven drug approvals for weight reduction since 1996 (click on Obesity.graffle). Between May 1996 and April 1999, there were three NME (new molecular entity) drug approvals for weight reduction, i.e., Redux (dexfenfluramine), Meridia (sibutramine) and Xenical (orlistat), the first two of which have been withdrawn from the market due to toxicity concerns.

It would take another 13 years and 2 months until the next NME drug approval for weight reduction, i.e., Belviq (lorcaserin), in June 2012. Since then there have been three additional drug approvals for weight reduction, but none of these involved NME drug approvals. One of these three, Saxenda (glucagon-like peptide-1 receptor agonist), was originally approved as Victoza “as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus”, and the other two involved combination products of previously approved drugs, one with one active constituent in the same therapeutic class, i.e., Qsymia (phentermine + topiramate), and one with neither active constituent previously approved in this therapeutic class, i.e., Contrave (buspirone + naltrexone). Note that phentermine is one of the origninal “old” norepinephrine releasers, and topiramate is an approved antiepileptic drug (Topamax). All of these latest four drug approvals have the indication “as an adjunct to a reduced-calorie diet and increased physical activity for chronic weight management in adults”.

Considering approved weight reduction drugs, with early approvals around 1960 involving the original norepinephrine releasers as appetite suppressors and intended for short-term use, both progression and innovation in this therapeutic class since then appears slow when compared with numerous other classes. One noteworthy recent development involves the introduction of combination products of previously approved drugs; it will be interesting to see if this becomes a trend in this class. One thing seems clear: there is a need for innovative treatment approaches and options to address obesity and obesity-associated morbidity.

Refer to page 18 of Progression of Modern Therapeutics (2014 Report) available under Reports on this website; this report also includes the methodology used. Note the non-NME drug approvals not included in the report are included in this post.