New Medications for Obesity – US Only?

Following yesterday’s announcement of the recognition of obesity as a “disease” by the American Medical Association, I speculated on what impact this may have on access to treatments.

While in the US, the FDA has recently approved two new medications for obesity (and is considering a third), not much is happening in other jurisdictions.

In an article we just published in Nature Reviews Endocrinology, Christian Rueda-Clausen, Raj Padwal and I review the available data on these drugs.

As we note in the article,

“Lifestyle and behavioural interventions aimed at reducing calorie intake and/or increasing energy expenditure have limited long-term effectiveness due to complex and persistent hormonal, metabolic and neurochemical adaptations that defend against weight loss and promote weight regain.”

This leaves a substantial therapeutic gap for those not eligible for or not wanting bariatric surgery – a gap that can theoretically be filled with medications (as we have for hypertension, diabetes, dyslipidemia, gout and countless other “diseases”).

In this paper we review the available data on the efficacy and safety of these three medications (lorcaserin, phentermine-topiramate controlled release and naltrexone sustained release-bupropion) and discusses future perspectives and challenges related to pharmacological weight management

While not everyone will respond to or tolerate these medications – they do represent a step forward in our ability to better treat a condition for which we have very little to offer.

Thus, we note that,

“The FDA approval of lorcaserin and phentermine–topiramate CR and the pending FDA decision on naltrexone SR–buproprion SR, are developments that address important therapeutic gaps in the management of obesity. Given both the poor long-term outcome of lifestyle interventions and the risks and limited availability of bariatric surgery, use of antiobesity medications in conjunction with lifestyle modification can lead to clinically meaningful weight loss in the range of 5–10%.”

However, we also caution that,

“…despite clinically significant improvements in metabolic and cardiovascular risk profiles seen with these agents, benefits have yet to be demonstrated in terms of improvements in ‘hard’ cardiovascular outcomes, for example, myocardial infarction, stroke and death. Results from large outcome trials investigating these new medications are expected to be completed in the coming 3–5 years.”

Unfortunately, so far access to these medications is limited to the US – hopefully, this will not remain the case for long.

@DrSharma
Edmonton, AB

Disclaimer: I have received honoraria for speaking and consulting from the makers of these medications (Arena, Vivus, Orexigen).

Rueda-Clausen CF, Padwal RS, & Sharma AM (2013). New pharmacological approaches for obesity management. Nature reviews. Endocrinology PMID: 23752772

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