Fixed-Ratio Combinations.

Combination treatment with basal insulin and a glucagon-like peptide-1 (GLP-1) receptor agonist targets different aspects of the pathophysiology of type 2 diabetes to achieve glycemic control. In November 2016, the U.S. Food and Drug Administration approved two titratable fixed-ratio combinations (FRCs) of basal insulin and a GLP-1 receptor agonist: insulin glargine/lixisenatide 3:1 ratio (iGlarLixi [Soliqua]) and insulin degludec/liraglutide 1:0.036 ratio (IDegLira [Xultophy]) (1,2). Both agents are indicated to improve glycemic control in adults with type 2 diabetes inadequately controlled on basal insulin or the respective GLP-1 receptor agonist along with diet and exercise (1,2). Use of these agents is not recommended for patients with type 1 diabetes, diabetic ketoacidosis, gastroparesis, or a history of pancreatitis. Additionally, these agents should be avoided in patients using another GLP-1 receptor agonist or prandial insulin (1,2). Insulin glargine and insulin degludec improve glycemic control through stimulation of glucose uptake in the body and inhibition of glucose production in the liver (1,2). Lixisenatide and liraglutide mimic the action of GLP-1 through stimulation of glucose-dependent insulin release, suppression of glucagon production, and slowing of gastric emptying (1,2). A main advantage of FRCs, as single daily injections of two glycemic control medications, is regimen simplification to promote treatment adherence with less potential for clinical inertia. Greater efficacy in glycemic control is …