Real-world medication persistence and outcomes associated with basal insulin and glucagon-like peptide 1 receptor agonist free-dose combination therapy in patients with type 2 diabetes in the US

Abstract

Background: Free-dose combination treatment with basal insulin and short-acting glucagon-like peptide-1 receptor agonists (GLP-1 RAs) reduces hyperglycemia via complementary targeting of fasting and postprandial blood glucose levels, however, in the real world, due to injection burden and clinical inertia, the full efficacy may not be able to translate into clinical and economic benefits.

Objective: The aim of the study was to evaluate treatment persistence and associated outcomes in patients with type 2 diabetes (T2D) treated with a GLP-1 RA in free-dose combination with basal insulin.

Methods: Claims data were extracted on US adults with T2D with ≥1 prescription claim for both a GLP-1 RA and a basal insulin from July 1, 2008 to June 30, 2013, and continuous health plan coverage for 6 months prior to (baseline) and 12 months after the index date (follow-up period). Outcomes analyzed for patients stratified by treatment persistence included glycemic control, hypoglycemia, and health care costs and resource utilization. Multivariate analyses were used to examine factors associated with persistence or hypoglycemia.

Results: The analysis included 7,320 patients, of whom 16.9% were persistent with free-dose combination treatment. The median time to treatment discontinuation was 133 days. Compared with nonpersistent patients, persistent patients had greater glycated hemoglobin A1c (A1C) reductions (-0.80% vs -0.42%; P=0.032), were more likely to achieve A1C <7.0% (39% vs 22%; P<0.001), and were less likely to experience hypoglycemia (9.5% vs 6.8%; P=0.002). Persistent patients also had significantly fewer hospitalizations and shorter hospital stays. While prescription costs were significantly higher (all-cause: $14,691 vs $10,791; P<0.001; diabetes-related: $8,142 vs $5,124; P<0.001), total medical charges were significantly lower (all-cause: $28,405 vs $40,292; P=0.001; diabetes-related: $11,114 vs $15,203; P=0.003) for persistent patients compared with nonpersistent patients.

Conclusion: This retrospective claims study of US patients with T2D showed that, although persistence with concurrent GLP-1 RA and basal insulin treatment is low, improved treatment persistence is associated with greater A1C reductions and lower total medical charges.

Keywords: GLP-1 receptor agonist; basal insulin; treatment persistence; type 2 diabetes.

Conflict of interest statement

This study was funded by Sanofi US, Inc. Melissa Lingohr-Smith and Jay Lin are employees of Novosys Health, under contract with Sanofi US, Inc. Tao Fan is an employee of Sanofi US, Inc. The authors report no other conflicts of interest in this work.

Figures

Figure 1

(A) Participant flow chart. (B) Schematic of study design. Notes: *The initiation of the second drug in the combination therapy (eg, insulin plus GLP-1, or GLP-1 plus insulin) is defined as the index event, with the corresponding date as the index date. To ensure that patients received combination therapy after the index date, they were required to have ≥14 days of overlap for both therapies in the 90 days after the index date. Abbreviations: T2D, type 2 diabetes; GLP-1, glucagon-like peptide-1.

Figure 2

Kaplan–Meier curve of median time to discontinuation of combination therapy.

Figure 3

All-cause (A) and diabetes-related (B) health care costs over the 12 months of follow-up. Abbreviation: ED, emergency department.