By Nicole Mackee
Liraglutide therapy coupled with lifestyle measures may curb the risk of type 2 diabetes in overweight and obese patients with prediabetes, say researchers in The Lancet.
In a randomised, double-blind controlled trial (the industry-funded SCALE obesity and Prediabetes trial), 2254 patients were randomised to either once-daily subcutaneous liraglutide (3 mg) or matched placebo, in conjunction with a reduced-calorie diet and increased physical activity. After three years of treatment, 2% of the liraglutide group and 6% of the placebo group had been diagnosed with diabetes. Patients in the treatment group lost 6.1% of their bodyweight (about 6 kg), compared with 1.9% (about 2 kg) in the placebo group.
Time to diabetes diagnosis was 2.7 times longer in the liraglutide group compared with placebo, which corresponded with a risk reduction of about 80%, the researchers said.
Professor Katherine Samaras, Laboratory Head, Clinical Obesity, Nutrition and Adipose Biology at the Garvan Institute of Medical Research, Sydney, welcomed the findings, but said they should be interpreted cautiously.
‘In this study, there was three times the weight loss in the liraglutide arm as there was on the placebo arm, so it appears that liraglutide may produce its reduction in the progression to overt diabetes through modest weight loss – while it is in use,’ said Professor Samaras, who is also Professor of Medicine at St Vincent’s Clinical School, University of NSW.
Professor Samaras pointed to the sharp return to baseline fasting glucose levels of 5.5 mmol/L in the 12 weeks after treatment cessation.
‘It does not appear to be an enduring effect,’ she said. ‘The fasting glucose level seems to rapidly return to baseline level within weeks of stopping the liraglutide, and that occurred in the fairly selected group of participants who were included in the study.’
Study participants were aged over 18 years with a stable body weight and a body mass index of at least 30 kg/m2 or at least 27 kg/m2 with comorbidities. They were all diagnosed with prediabetes, meeting at least one of the three American Diabetes Association criteria for this condition.
Professor Samaras said the study demonstrated the significant impact that modest weight loss could have in halting the progression to overt type 2 diabetes.
‘We know from prior studies that weight loss in this group will prevent the progression to type 2 diabetes, as we know that lifestyle plus metformin will also halt 50 to 60% of cases of prediabetes progressing to overt diabetes,’ Professor Samaras told Endocrinology Today.
‘Liraglutide is now another tool that we have in our armamentarium for managing patients with obesity and prediabetes, but it does not appear to be an enduring magic bullet.’
Lancet 2017; doi: 10.1016/S0140- 6736(17)30069-7.