The weight loss drug lorcaserin shows promise for reducing the risk of diabetes and aiding patients with the disease, according to a recent study by Brigham researchers.

Approved by the U.S. Food and Drug Administration in 2012 for adults with obesity – and those who are overweight and have weight-related medical problems – lorcaserin controls a patient’s appetite by triggering feelings of fullness. Investigators from the Thrombolysis in Myocardial Infarction (TIMI) Study Group led a clinical trial to test the effects of lorcaserin, manufactured by the trial’s sponsor, Eisai Inc., in 12,000 overweight or obese patients at risk for a heart attack or stroke. At the start of the trial, more than half of participants had diabetes and another third had prediabetes.

Erin Bohula

During this year’s European Association for the Study of Diabetes and in a simultaneous publication in The Lancet, the research team reported that taking lorcaserin decreased risk for diabetes, induced diabetes remission and reduced risk of diabetes complications in obese and overweight patients.

These latest findings build on a related discovery the same team of Brigham investigators reported earlier this year on the cardiovascular safety and weight loss effectiveness of lorcaserin.

“We recently presented findings showing that use of lorcaserin resulted in modest but sustained weight loss among obese and overweight patients without increasing risk of heart attack and stroke,” said co-lead author Erin Bohula, MD, DPhil, a cardiovascular medicine and critical care specialist in the Division of Cardiovascular Medicine and a staff investigator for the TIMI Study Group. “Now we report that, when added to lifestyle interventions, lorcaserin significantly reduced incidence of diabetes, increased rates of diabetes remission and reduced the risk of diabetic microvascular complications.”

Benjamin Scirica

Researchers found that lorcaserin reduced risk of diabetes by 19 percent in prediabetic participants. Among those with diabetes, 21 percent saw a reduced risk of diabetic microvascular complications, which affect small blood vessels and lead to issues in the kidney (persistent microalbuminuria), eyes (diabetic retinopathy) or nerves (diabetic neuropathy).

“Lorcaserin provides another tool, beyond diet and exercise, for patients hoping to achieve and maintain weight loss. And, happily, even relatively modest weight loss can improve the diabetes control in those with diabetes and reduce the development of diabetes in those at risk,” said co-lead author Benjamin Scirica, MD, also of Cardiovascular Medicine and a senior investigator for the TIMI Study Group.

Hypoglycemia, or dangerously low levels of blood sugar, could be a negative side effect of taking lorcaserin for patients already on medications to lower blood sugar. For example, among participants taking insulin or a sulfonylurea (a medication to treat Type 2 diabetes), researchers reported more events of severe hypoglycemia requiring hospitalization or considered to be life-threatening – recording 12 events with lorcaserin versus four events with a placebo. The authors note that this finding highlights the importance of carefully adjusting agents known to increase risk of hypoglycemia, especially while a patient is working to lose weight.

“Given the global prevalence of obesity and its association with Type 2 diabetes and complications that can cause death or greatly diminish quality of life, we need therapeutic strategies that can be added to lifestyle modification to prevent and control diabetes,” said Scirica. “This rigorous and large-scale randomized study demonstrates the potential for improving glycemic control when adding a weight loss agent to a treatment plan.”