OBJECTIVES

Sodium-glucose cotransporter (SGLT) 2 inhibitors (and combined SGLT1/2 inhibitors) decrease renal glucose reabsorption, promoting glucose excretion in the urine (glucosuria). They have been shown to improve glycemic control in patients with type 2 diabetes with no increase in hypoglycemia. The aim of the present study was to use a modern model of type 1 diabetes to conduct a cost-utility analysis of adding SGLT inhibitors to basal-bolus insulin therapy in the US.

METHODS

The PRIME Diabetes Model (PRIME) was used to evaluate the cost-utility of adding SGLT inhibitors to basal-bolus insulin, adopting the perspective of a comprehensive US healthcare payer over a 60-year time horizon. Treatment effects were taken from a recent meta-analysis, and cohort characteristics were based on an SGLT1/2 inhibitor trial including data collected at 33 US sites. Quality of life utilities and US-specific costs were identified from the literature and the IBM Micromedex^® RED BOOK^® database, with costs expressed in 2018 US dollars (USD). Future costs and effects were discounted at 3% per annum and one-way and probabilistic sensitivity analyses were conducted.

RESULTS

Adding SGLT inhibitors to basal-bolus insulin improved quality-adjusted life expectancy by 0.10 quality-adjusted life years (QALYs) to 12.26 QALYs, accompanied by an increase in lifetime costs of USD 5,363, yielding an incremental cost-utility ratio of USD 52,774 per QALY, fractionally over a willingness-to-pay (WTP) threshold of USD 50,000 per QALY, the lowest WTP threshold used by the Institute for Clinical and Economic Review.

CONCLUSIONS

The analysis was extensively tailored to the US setting, with the model itself based in part on US clinical data, populated with US-specific drug cost, complication cost and mortality data. Based on data from a recent meta-analysis, addition of SGLT inhibitors to basal-bolus insulin in patients with T1D would be borderline cost-effective from a comprehensive US healthcare payer perspective.