Glucose-Lowering Effects and Low Risk of Hypoglycemia in Patients With Maturity-Onset Diabetes of the Young When Treated With a GLP-1 Receptor Agonist: A Double-Blind, Randomized, Crossover Trial

OBJECTIVE The most common form of maturity-onset diabetes of the young (MODY), hepatocyte nuclear factor 1 alpha (HNF1A diabetes: MODY3) is often treated with sulfonylureas that confer a high risk of hypoglycemia. We evaluated treatment with GLP-1 receptor agonists (GLP-1RAs) in patients with HNF1A diabetes. RESEARCH DESIGN AND METHODS Sixteen patients with HNF1A diabetes (8 women; mean age 39 years [range 23-67 years]; BMI 24.9 +/- 0.5 kg/m(2) [mean +/- SEM]; fasting plasma glucose [FPG] 9.9 +/- 0.9 mmol/L; HbA(1c) 6.4 +/- 0.2% [47 +/- 3 mmol/mol]) received 6 weeks of treatment with a GLP-1RA (liraglutide) and placebo (tablets), as well as a sulfonylurea (glimepiride) and placebo (injections), in randomized order, in a double-blind, crossover trial. Glimepiride was up-titrated once weekly in a treat-to-target manner; liraglutide was up-titrated once weekly to 1.8 mg once daily. At baseline and at the end of each treatment period a standardized liquid meal test was performed, including a 30-min light bicycle test. RESULTS FPG decreased during the treatment periods (-1.6 +/- 0.5 mmol/L liraglutide [P = 0.012] and 22.8 +/- 0.7 mmol/L glimepiride [P = 0.003]), with no difference between treatments (P = 0.624). Postprandial plasma glucose (PG) responses (total area under the curve) were lower with both glimepiride (2,136 +/- 292 min x mmol/L) and liraglutide (2,624 +/- 340 min x mmol/L) compared with baseline (3,127 +/- 291 min x mmol/L; P < 0.001, glimepiride; P = 0.017, liraglutide), with no difference between treatments (P = 0.121). Eighteen episodes of hypoglycemia (PG <= 3.9 mmol/L) occurred during glimepiride treatment and one during liraglutide treatment. CONCLUSIONS Six weeks of treatment with glimepiride or liraglutide lowered FPG and postprandial glucose excursions in patients with HNF1A diabetes. The glucose-lowering effect was greater with glimepiride at the expense of a higher risk of exclusively mild hypoglycemia.