Cost-Effectiveness of Once-Weekly Semaglutide 1 mg versus Canagliflozin 300 mg in Patients with Type 2 Diabetes Mellitus in a Canadian Setting

Abstract

Objective Our objective was to evaluate the long-term cost-effectiveness of once-weekly semaglutide 1 mg versus once-daily canagliflozin 300 mg in patients with type 2 diabetes mellitus (T2DM) uncontrolled with metformin from the healthcare payer and societal perspectives in Canada. Methods Head-to-head data from the SUSTAIN 8 randomised trial (NCT03136484) were extrapolated over 40 years using economic simulation modelling. The cost-effectiveness of once-weekly semaglutide 1 mg versus canagliflozin 300 mg for treating T2DM was estimated using the Swedish Institute for Health Economics-Diabetes Cohort Model (IHE-DCM) and the Economic and Health Outcomes Model of T2DM (ECHO-T2DM). Unit costs and disutility weights capturing treatments and key macro- and microvascular complications were sourced from the literature to best match the Canadian setting. A probabilistic base-case simulation and sensitivity analyses were conducted. Results Once-weekly semaglutide 1 mg was associated with reductions in macro- and microvascular complications, yielding incremental cost-effectiveness ratios (ICERs) of (Canadian dollars [CAD]) CAD16,392 and 18,098 per incremental quality-adjusted life-year (QALY) gained versus canagliflozin 300 mg for IHE-DCM and ECHO-T2DM, respectively, from a healthcare payer perspective. Accounting for productivity loss as well, ICERs were CAD14,127 and 13,188 per QALY gained for IHE-DCM and ECHO-T2DM, respectively, from a societal perspective. Sensitivity analyses confirmed that the base-case results were robust to changes in input parameters and assumptions used. Conclusions At a willingness-to-pay threshold of CAD50,000 per QALY gained, once-weekly semaglutide 1 mg was cost-effective over 40 years versus once-daily canagliflozin 300 mg for the treatment of T2DM in patients failing to maintain glycemic control with metformin alone. Supplementary Information The online version contains supplementary material available at 10.1007/s40258-022-00726-z.

A Systematic Review of Cost-Effectiveness Studies of Newer Non-Insulin Antidiabetic Drugs: Trends in Decision-Analytical Models for Modelling of Type 2 Diabetes Mellitus

“…Injectable semaglutide was found to be cost effective in all comparisons with empagliflozin [49,57,59] except one [59]. Injectable semaglutide was also found to be cost effective against canagliflozin [73]. Empagliflozin dominated liraglutide in all their comparisons [45,56,72,77].…”

“…The results of extracted data from included studies can be found in Table 1, which summarises the general characteristics of the studies. The majority of studies (n = 30) were conducted in Europe , of which many were conducted in the UK (n = 9) [37,38,40,45,46,48,51,57,62], and one-third of the studies were conducted in North America (n = 10) [64][65][66][67][68][69][70][71][72][73] and Asia (n = 8) [74][75][76][77][78][79][80][81]. Two studies were conducted outside these regions: one each from Colombia [82] and Iran [83].…”

“…The vast majority of modelling studies (n = 24) [36-43, 45-49, 51-53, 56-59, 61-63, 77] used IQVIA's CORE Diabetes Model (CDM) [84,85], followed by the Cardiff Diabetes Model [86] (n = 5) [34,50,54,75,82], the Swedish Institute for Health Economics Cohort Model for T2DM (IHE-DCM) [87] (n = 5) [35,44,60,68,81], the UK Prospective Diabetes Study (UKPDS) Outcomes Model 2 (UKPDS-OM2) [88] (n = 3) [64,76,79], the Chinese Outcomes Model for T2DM (COMT) [89] (n = 2) [74,78], and one study each with the Economic and Health Outcomes Model of T2DM (ECHO-T2DM) [90] and the Discretely Integrated Condition Event platform [91]. One study used both the IHE-DCM and the ECHO-T2DM to produce and compare their results [73]. Eight studies did not state the model name, of which three studies [71,80,83] used Markov state transition models, three used individual patient simulations [55,67,72], and one each used a state transition cohort model with a competing risk approach [70] and a decision tree [65].…”

“…Less frequently, a healthcare sector perspective (n = 10) [56,58,59,71,74,76,[78][79][80][81] and a societal perspective were used in six studies [35,43,44,53,54,68]. Two studies used both a payer's perspective and a societal perspective [60,73], while the perspective employed by one study was unclear [82].…”

“…In the majority of studies (n = 21), a willingness-topay (WTP) threshold similar to that used in the UK (GBP20-30,000/quality-adjusted life-years [QALYs] or equivalent value in Euros or local currency) was utilised [34, 36-40, 45-55, 57, 61-63], followed by the World Health Organisation (WHO)-recommended WTP threshold of one to three times the gross domestic product per capita (n = 14) [41,56,58,59,[74][75][76][77][78][79][80][81][82][83]. The remaining studies used a North American WTP threshold (n = 9) [64][65][66][67][68][69][70][71]73] or a Swedish threshold (n = 3) [35,60], and one study each used thresholds specific to The Netherlands [43] and Slovakia [42], while the last study did not state a threshold [72]. A total of 116 ICER estimates for base cases and reported scenarios were extracted from the included studies.…”