Pharmacoeconomic aspects of treatment with fixed combinations: dipeptidyl peptidase-4 inhibitors + metformin vs sulfonylurea + metformin in patients with type 2 diabetes: retrospective analysis of Russian national registry of diabetes registry data for 2010-2017

Aim. Evaluate pharmacoeconomic aspects at the start of drug therapy with fixed combinations dipeptidyl peptidase-4 inhibitors (iDPP-4) + metformin vs fixed combinations sulfonylurea (SU) + metformin in patients with type 2 diabetes in real-world clinical practice. Materials and methods. This study utilized the data from the National Registry of Diabetes (NRD). The following inclusion criteria was used: patients who received drug therapy with fixed combinations, which had been prescribed for the first time over the period 2010-2017. Subsequently, two comparison groups were created from the pool of selected patients, comparable by gender and age, with no complications at the start of treatment. The total number of patients with T2DM, whose data had been reviewed during the study, was 36 100 patients: n=18 080 in SU + metformin group and n=18 020 in iDPP-4 + metformin group. All the patients with the given characteristics who were on continuous treatment for the said period were analyzed for HbA-, levels and BMI at the start of treatment and overtime (2018). We established as the principal clinical and economic criterion for evaluating the selected treatment models, the lack of diabetic complications (% of patients without complications in each of the studied groups). Methods used for pharmacoeconomic analysis included: cost-effectiveness analysis, budget impact analysis and cost minimization analysis. Also, based on the cost-effectiveness analysis, a cost-effectiveness ratio (CER) was calculated. Results. The rate of complications recorded in iDPP-4 + metformin group was lower than in SU + metformin group: for eye-related complications (diabetic retinopathy and cataract) it was lower by 1.9 times (2.7% vs 5.2%; p<0.01) and for cardiovascular complications - by 1.8 times (3.0% vs 5.3%; p<0.01). As for lower limb complications (diabetic foot syndrome and amputation) there was no statistically significant difference between the groups (0.7% vs 0.7%; p>0.9). Taking into account the direct medical, direct non-medical and indirect costs related to treatment of diabetic complications, the cost of iDPP-4 + metformin treatment per patient per year was 32 776 rubles, which is 35% lower than that for SU + metformin (50 122 rubles). The calculation model used in budget impact analysis demonstrated that with an increase in the proportion of patients who start treatment with iDPP-4 + metformin instead of routinely prescribed SU + metformin from 13% to 50%, and factoring in the number of naive T2DM patients, the public spending would be reduced by 166 million rubles per year, or by 832 million rubles over 5 year period. Based on the cost-effectiveness analysis, the calculated CER value for iDPP-4 + metformin was 73 079 rubles compared to 66 954 rubles for SU + metformin. The average cost of SU + metformin therapy per year was 9313 rubles vs 38 786 rubles for iDPP-4 + metformin (>316%), and following costeffectiveness analysis the difference in favor of SU + metformin was only 9%. In iDPP-4 + metformin group, the CER values were within the range from 82 459 rubles to 57 337 rubles, in SU + metformin group - 66 954 rubles. Conclusion. The performed clinical and economic analysis of NRD database showed the lower rate of micro- and macro-vascular complications in patients on fixed combinations iDPP-4 + metformin compared with patients on SU + metformin, as well as better cost-effectiveness. Among the fixed combinations iDPP-4 + metformin with equivalent clinical efficacy, the lowest cost combination is alogliptin + metformin. Key words: iDPP-4, SU, Registry of Diabetes, cost analysis, cost-effectiveness analysis, budget impact analysis, cost minimization analysis. For citation: Bukharov K.G., Vikulova O.K., Galstyan G.R. et al. Pharmacoeconomic aspects of treatment with fixed combinations: dipeptidyl peptidase-4 inhibitors + metformin vs sulfonylurea + metformin in patients with type 2 diabetes: retrospective analysis of Russian national registry of diabetes registry data for 2010-2017. Consilium Medicum. 2020; 22 (4): 18-26. DOI: 10.26442/20751753.2020.4.200106

iDPP-4, SU, Registry of Diabetes, cost analysis, cost-effectiveness analysis, budget impact analysis, cost minimization analysis