David B. Allison, Ph.D., distinguished professor and associate dean for science in the UAB School of Public Health.
More than one-third of adults in the U.S. are obese, which can lead to many related conditions, including heart disease, stroke, type 2 diabetes and certain types of cancer, according to the Centers for Disease Control and Prevention.
Lorcaserin is to be used in addition to a reduced-calorie diet and exercise
program in adults with a body mass index of more than 30 (obese) or for
those with a BMI of more than 27 (overweight) who also suffer from at
least one weight-related condition, according to the FDA.
Allison says orlistat and phentermine were the only other FDA-approved weight-loss drugs available, prior to lorcaserin's approval, but both have drawbacks of their own. Orlistat is very safe, but with modest efficacy, says Allison, and phentermine has slightly better efficacy but is not approved for long term use.
“An additional drug in the arsenal is very important because not everybody responds to drugs in the same way, so having another drug gives more options to try,” Allison explains.
As for why there are currently so few approved anti-obesity drugs, Allison points to a concern he says is legitimate.
“There is a worry that many non-obese persons who want to lose a modest amount of weight for cosmetic or social reasons will get access to these drugs,” Allison says. “This is a legitimate concern, but we should not let the fact that some people will use or try to use a medication outside it's appropriate use prevent us from getting that drug to patients who legitimately need and can benefit from it.”
W. Timothy Garvey, M.D., chair of the UAB Department of Nutrition Sciences, says the approval of a new anti-obesity drug has been a long time coming, as clinicians have faced a void for therapeutic options to offer patients in addition to lifestyle modification and bariatric surgery.
“While lifestyle modification is helpful, it’s not successful in long term weight loss. So the advent of medications is very exciting because it expands the options to offer patients and will help reduce the burden of patient suffering, the cost of obesity, and most importantly the progression to diabetes,” says Garvey.
Garvey warns that while anti-obesity drugs are useful tools in the fight against obesity, they can’t be viewed as the only tool.
“Many clinical trials have been done on this new drug where the placebo group undergoes a lifestyle intervention and the experimental group gets the drug and has a lifestyle intervention. There’s no data on how effective this medication is in the absence of lifestyle intervention; it is not a magic pill – people need to engage in lifestyle modification when taking this drug,” Garvey says.
Garvey and Allison have both also been involved in most of the clinical trials for another anti-obesity drug, a combination of topiramate and phentermine, which is up for FDA approval on July 17. This medication was recommended for approval by an FDA advisory committee in early 2012 and has shown in clinical trials to produce good weight-loss results in obese persons.
“We hope that scientists continue to work on the development of truly new anti-obesity treatments that have even greater efficacy and safety as well as alternative mechanisms of action to further increase the options for patients,” Allison says.
Garvey has received research support, has served on advisory boards for,
and also holds stock in the drug manufacturer of the phentermine and
topiramate combination, Vivus, Inc. Allison has received payments or other benefits from non-profit and for-profit organizations with interests in obesity, including the Frontiers Foundation; Vivus, Inc; Merck; Eli Lilly & Company; Pfizer; Jason Pharmaceuticals; Kraft Foods; Arena, Orexigen, University of Wisconsin; University of Arizona; Paul, Weiss, Wharton & Garrison LLP; and Sage Publications.