Weight Loss Drug Helped Prevent Diabetes in Overweight People

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BERLIN -- In overweight and obese patients with type 2 diabetes, lorcaserin (Belviq) helped improve blood glucose levels, according to the CAMELLIA-TIMI 61 trial.

After 1 year of 10 mg, twice-daily treatment, patients saw a significant 0.33% (95% CI 0.29-0.38%, P<0.0001) drop in mean HbA1c level compared with those receiving placebo, reported Erin Bohula, MD, DPhil, of Brigham and Women's Hospital in Boston, and colleagues.

There was also a 19% risk reduction seen for incident type 2 diabetes among those who had prediabetes at baseline (HR 0.81, 95% CI 0.66-0.99, P=0.038), as well as a 23% risk reduction among those free of diabetes at baseline (HR 0.77, 0.63-0.94, P=0.012).

"We can't say for sure there's more than one potential mechanism [behind the glycemic benefit], although my suspicion is that much of it is related to weight loss," Bohula stated during a press conference of the findings at the annual meeting of the European Association for the Study of Diabetes (EASD). The results were also simultaneously published in The Lancet.

Lorcaserin was originally FDA approved back in 2012 for chronic weight management as an adjunct therapy to lifestyle modification, although the drug is not available in Europe.

In the multicenter trial, lorcaserin only somewhat helped those with prediabetes achieve a normal glucose range, although this did not reach significance (HR 1.20, 0.97-1.49, P=0.093).

Not surprisingly, the patients who received lorcaserin also had a significant amount of weight loss compared with placebo, seen across all groups of diabetes status (P<0.0001 for all):

• Diabetes: loss of 5.7 lb (95% CI 5.1-6.4 lb) [2.6 kg, 2.3-2.9 kg]
• Prediabetes: loss of 6.2 lb (95% CI 5.5-7.1 lb) [2.8 kg, 2.5-3.2]
• Normoglycemia: loss of 7.3 lb (95% CI 5.7-8.8 lb) [3.3 kg, 2.6-4.0 kg]

A total of 12,000 adults age 40 and older were included in the trial: 6,816 patients with diabetes, 3,991 who were identified as having prediabetes -- defined as an A1c between 5.7% to <6.5% -- and 1,193 with normoglycemia. All participants had a body mass index of 27+ at baseline with established atherosclerotic cardiovascular disease or other cardiovascular-related risk factors. All patients were encouraged to be involved in a weight management program that was freely available to them, but there was no further treatment given beyond the drug. The participants were then followed for a median 3.3 years.

Questions about Clinical Significance

In an accompanying commentary, Xabier Unamuno, MSc, and Gema Frühbeck, MD, PhD, of the University of Navarra in Pamplona, Spain, were somewhat wary of the findings: "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 there was statistically significant net weight loss seen across all groups, it was only moderate at best and "might not be clinically significant."

Unamuno and Frühbeck said that ultimately, clinicians may find this weight loss "disappointing, especially if it does not lower the risk of cardiovascular disease," as was seen in the trial's previously reported cardiovascular outcomes, presented earlier this year at European Society of Cardiology.

The commentary noted that because not everyone will respond to lorcaserin, physicians may instead consider initially prescribing it only on a temporary basis of around 6-12 months in order to distinguish responders from non-responders. "It is difficult to quantify the risk of chronic use versus meaningful clinical improvement. Treatment on an intermittent basis, to maximize the benefits of the first months, might be considered."

During the press conference, Bohula also noted that the renal outcomes -- microalbuminuria, eGFR, and chronic kidney disease progression -- from the trial will be presented later this year at the American Heart Association (AHA) meeting in November.