Cost-effectiveness of dapagliflozin as an adjunct to insulin for the treatment of type 1 diabetes mellitus in the United Kingdom

Aims To assess the cost-effectiveness of dapagliflozin, a sodium-glucose co-transporter-2 (SGLT2) inhibitor, as an adjunct to insulin in adults with type 1 diabetes mellitus (T1DM) inadequately controlled by insulin alone in the UK setting. Methods A cost-utility analysis was conducted to compare dapagliflozin (5 mg or 10 mg) added to insulin versus insulin monotherapy (standard of care) over a lifetime horizon. Treatment efficacy and safety data were obtained from 52-week results of the DEPICT-1 and DEPICT-2 trials and a network meta-analysis of SGLT2 inhibitors in T1DM. Direct healthcare costs, life-years, and quality-adjusted life-years (QALYs) were estimated from a UK payer perspective and discounted at 3.5% annually, using the Cardiff T1DM Model. Sensitivity analyses assessed uncertainty in estimated incremental cost-effectiveness ratios (ICERs). Results Dapagliflozin 5 mg was associated with gains of 0.23 life-years and 0.42 QALYs, at an additional cost of 4240 pound per person; corresponding to an ICER of 10 pound 143 versus standard of care. For dapagliflozin 10 mg, incremental life-years, QALYs and costs were 0.24, 0.49 and 2964 pound, respectively; corresponding to an ICER of 6103 pound versus standard of care. In probabilistic sensitivity analysis, ICER estimates fell below 20 pound 000/QALY in 78% to 90% of simulations. Cost-effectiveness results were sensitive to changes in baseline patient characteristics and treatment effects on glycated haemoglobin; however, ICERs remained below 20 pound 000. Conclusions At cost-effectiveness thresholds conventionally applied in the UK, dapagliflozin as an adjunct to insulin appears to be a cost-effective treatment option for people with T1DM inadequately controlled by insulin alone.