Glycemic Control Following GLP-1 RA or Basal Insulin Initiation in Real-World Practice: A Retrospective, Observational, Longitudinal Cohort Study

Introduction: Injectable therapies such as glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and basal insulin (BI) are well-established agents for people with type 2 diabetes (T2D). This study aimed to investigate real-world effectiveness of GLP-1 RAs or BI in adults with T2D poorly controlled on oral antihyperglycemic drugs (OADs).

Methods: This was a retrospective, observational, longitudinal cohort study of adults with T2D from the US Optum Humedica® database and UK Clinical Practice Research Datalink, who initiated either injectable between January 1, 2010 and June 30, 2016. Baseline characteristics, glycated hemoglobin (HbA1c) change, and cumulative percentage reaching HbA1c <7% in 24 months after initiation were analyzed in 4 patient cohorts.

Results: In the US and UK databases, respectively, 20,836 and 5508 patients initiated GLP-1 RAs, and 60,598 and 5083 initiated BI. Baseline mean HbA1c at initiation ranged between 8.8% and 10.3% across all cohorts. In all cohorts, a decrease of HbA1c occurred 3–6 months after initiation. The cumulative percentage of patients reaching HbA1c <7% showed the greatest probability in the first 12 months (15%–40% of patients across cohorts at 12 months), particularly in the first 6 months after initiation. The probability of reaching glycemic control diminished after the second quarter. The proportion of patients reaching HbA1c <7% in both GLP-1 RA and BI cohorts at 12 months was <25% if baseline HbA1c was ≥9%.

Conclusions: For adults with T2D inadequately controlled on OADs, this analysis reveals an unmet clinical need. Initiation of first injectable therapy did not occur until HbA1c was considerably above target, when control is harder to achieve. Results suggest that in individuals with baseline HbA1c ≥9.0%, only a minority are likely to achieve an HbA1c <7% with a GLP-1 RA or BI alone.