Addition of Dulaglutide for a High-Dose Insulin Requiring Patient with Type 2 Diabetes Mellitus: A Remarkable Response

Abstract

Despite the availability of several new classes of antidiabetic medications, a large proportion of patients with diabetes mellitus fail to achieve optimal glycemic control. Adding glucagon-like peptide-1 receptor agonists (GLP1 RAs) to basal insulin regimens has shown to improve glycemic control in type 2 diabetes mellitus (T2DM). We present a patient with T2DM who had marked improvement in glycemic control accompanied by weight loss and a decrease in insulin requirement after adding weekly dulaglutide to U500 regular insulin. A 56-year-old man with T2DM, class III obesity (weight 314 pounds, body mass index 46.4 kg/m2), and hyperlipidemia had uncontrolled glycemia with a hemoglobin A1c (HbA1c) of 9.7% (83 mmol/mol) despite using high-dose insulin therapy and metformin. Physical examination was unremarkable except for obesity. His HbA1c remained high despite increments in insulin dosage up to 400 units per day. A few months after adding dulaglutide to his regimen, the patient's HbA1c declined to 6.3% (45 mmol/mol) despite significant reduction in daily insulin dosage to 20 units (94% decrease), which was accompanied by a 20-pound weight loss. The patient had a dramatic decrease in HbA1c, weight, and insulin requirement after treatment with dulaglutide. In the literature we could only find 1 study where a GLP1 RA (liraglutide) was successfully used in 15 patients receiving U500 insulin (average dose 197 ± 72 units/day). However, their reductions in weight and HbA1c were markedly less than observed in our patient. GLP1 RAs should be considered in patients with T2DM who require high-dose insulin therapy.