Appetite suppressant lorcaserin shrinks probability of incident diabetes

Lorcaserin, an appetite suppressant approved for chronic weight management in 2012, reduced overweight patients’ risk for developing type 2 diabetes (T2D) and improved remission of hyperglycemia in a study of more than 12,000 Massachusetts residents, researchers reported.

The study, presented at this year’s European Association for the Study of Diabetes conference in Berlin, and published simultaneously in the Lancet, randomized thousands of participants to treatment with 10 milligrams of lorcaserin twice a day or placebo between February 2014 and November 2015. Patients were followed for an average of three years and assessed for a primary endpoint of incident diabetes. 

Lead investigator Erin A. Bohula, MD, and colleagues with the TIMI Study Group in the Division of Cardiovascular Medicine at Brigham and Women’s Hospital in Boston, said the trial aimed to evaluate the efficacy of lorcaserin, a selective serotonin 2C receptor. Specifically, the researchers wanted to study the drug's ability to improve glycemic control for patients prone to T2D—control those patients need to avoid cardiovascular complications, chronic kidney disease and death.

“Pharmacological weight loss agents are guideline-recommended adjuncts to lifestyle modification for long-term weight management and for the prevention of prediabetes and diabetes,” Bohula et al. wrote. “Predominantly short-term studies (typically one year in length) of pharmacological weight loss agents have shown improvements in glycemic parameters, but few long-term data from large, randomized trials are available.”

Of Bohula and colleagues’ research population, 57 percent presented with diabetes at baseline, the authors said. Another third had been diagnosed with prediabetes, and 10 percent registered with healthy blood sugar levels.

A year after the launch of CAMELLIA-TIMI 61, Bohula and co-authors said patients with baseline diabetes, prediabetes and normoglycemia saw net weight losses of 2.6 kg, 2.8 kg and 3.3 kg, respectively. All results were statistically significant, they said.

Lorcaserin also affected patients in the following ways:

  • Reduced the risk of diabetes by 19 percent in patients with prediabetes
  • Increased the rate of remission of hyperglycemia by 21 percent in patients with diabetes
  • Reduced the risk of a composite of microvascular events by 21 percent in patients with diabetes
  • Reduced glycated hemoglobin by 0.3 percent in patients with diabetes

In patients with diabetes at baseline, severe hypoglycemia with serious complications was more common with lorcaserin, Bohula et al. wrote, but as a whole it was rare. 

While Bohula’s team touted their results, Xabier Unamuno and Gema Fruhbeck, both endocrinologists at the University of Navarra in Pamplona, Spain, said in a related editorial clinicians should take the trial with a grain of salt.

“Among the strengths of the study are the large sample size and a long study period,” Unamuno and Fruhbeck wrote. “However, from the endocrinologist’s point of view, both the design of the study and its results are somewhat puzzling—namely, in terms of the magnitude of the effect of lorcaserin and the anti-diabetes management of the patients. Although significant, [the net weight loss achieved] after one year of treatment with lorcaserin is moderate and might not be clinically significant.”

They said for some physicians, the resulting weight loss they’ll see from prescribing lorcaserin “might be disappointing”—especially if the drug fails to further lower the risk of CVD or other chronic conditions in patients.

The editorialists said physicians might be more comfortable prescribing lorcaserin on a temporary basis, suggesting somewhere between a 6- and 12-month regimen. Patients who respond well to the treatment and might benefit from continuation would be easily identified within a few months.

“It is difficult to quantify the risk of chronic use versus meaningful clinical improvement,” Unamuno and Fruhbeck said. “Treatment on an intermittent basis, to maximize the benefits of the first months, might be considered.”