Background: The high insulin costs have associated with underuse and poor adherence among patients with types 2 diabetes (T2D) . Basaglar was approved by FDA in 2015 as a follow-on insulin to reference insulin Lantus. It presents an opportunity to reduce costs and improve adherence to insulin treatment. The study assessed the change in HbA1c after initiation of follow-on insulin (Basaglar) or reference insulin (Lantus) among patients with T2D. We also compared treatment adherence, safety events, and costs at 1-year after initiation of insulin.

Methods: Using claims data from a large U.S. health plan during 2016-2020, we identified adults with T2D who initiated either Basaglar or Lantus. Generalized linear regression modeling assessed the differences in outcomes between the groups. A 0.4% margin was used to determine non-inferiority for HbA1c .

Results: The study included 1,136 Basaglar users and 6,3Lantus users. The mean age was 54.0 years in Basaglar users and 56.3 years in Lantus users (p<0.001) . Both groups showed more than 1% reduction in HbA1c over 6 months and over 12 months. Reduction in HbA1c with Basalgar was similar (noninferior) to that with Lantus, with an adjusted difference of Basaglar to Lantus of 0.14% (95% CI -0.02 to 0.30, p=0.084) over 6 months and 0.17% (95% CI 0.02 to 0.32, p=0.024) over 12 months. Rates of adverse events were similar for both hypoglycemia and vascular events. The Basaglar group showed higher adherence in terms of proportion of days covered (adjusted difference 0.06, 95% CI 0.08, p<0.001) . Medical costs were similar, but the cost of Basaglar was lower (adjusted mean cost difference -$462, 95% CI -$556 to -$363, p<0.001) after adjustment.

Conclusions: Basaglar provided similar glycemic control compared to Lantus, had similar safety profile and more favorable adherence in patients with T2D. The findings highlight the potential that biosimilar/follow-on biologics offer in terms of expanding patient access and improving treatment affordability.


X.Chen: None. T.Pham: Employee; Anthem, Inc. J.J.Barron: None. R.A.Hart: None. J.Abarca: None. A.Devries: None.

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