Cost-effectiveness of metformin plus vildagliptin compared with metformin plus sulphonylurea for the treatment of patients with type 2 diabetes mellitus: a Portuguese healthcare system perspective.
OBJECTIVE
To evaluate the cost-effectiveness of vildagliptin plus metformin vs generic sulphonylurea plus metformin in patients with type 2 diabetes mellitus, not controlled with metformin, from a Portuguese healthcare system perspective.


METHODS
A cost-effectiveness model was constructed using risk equations from the UK Prospective Diabetes Study Outcomes Model with a 10,000-patient cohort and a lifetime horizon. The model predicted microvascular and macrovascular complications and mortality in yearly cycles. Patients entered the model as metformin monotherapy failures and switched to alternative treatments (metformin plus basal-bolus insulin and subsequently metformin plus intensive insulin) when glycated hemoglobin A1c >7.5% was reached. Baseline patient characteristics and clinical variables were derived from a Portuguese epidemiological study. Cost estimates were based on direct medical costs only. One-way and probabilistic sensitivity analyses were conducted to test the robustness of the model.


RESULTS
There were fewer non-fatal diabetes-related adverse events (AEs) in patients treated with metformin plus vildagliptin compared with patients treated with metformin plus sulphonylurea (6752 vs 6815). Addition of vildagliptin compared with sulphonylurea led to increased drug acquisition costs but reduced costs of AEs, managing morbidities, and monitoring patients. Treatment with metformin plus vildagliptin yielded a mean per-patient gain of 0.1279 quality-adjusted life years (QALYs) and a mean per-patient increase in total cost of €1161, giving an incremental cost-effectiveness ratio (ICER) of €9072 per QALY. Univariate analyses showed that ICER values were robust and ranged from €4195 to €16,052 per QALY when different parameters were varied.


CONCLUSIONS
The model excluded several diabetes-related morbidities, such as peripheral neuropathy and ulceration, and did not model second events. Patients were presumed to enter the model with no diabetes-related complications.


CONCLUSIONS
Treatment with metformin plus vildagliptin compared with metformin plus sulphonylurea is expected to result in a lower incidence of diabetes-related AEs and to be a cost-effective treatment strategy.
Novartis Farma SA , Porto Salvo , Portugal.
Daniel
D
Viriato
Frederico
F
Calado
Jean-Bernard
JB
Gruenberger
Siew Hwa
SH
Ong
Davide
D
Carvalho
José
J
Silva-Nunes
Sukhvinder
S
Johal
Ricardo
R
Viana
D000218:Adamantane / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000191:economics; D003198:Computer Simulation; D003362:Cost-Benefit Analysis; D048909:Diabetes Complications / Q000191:economics* / Q000517:prevention & control; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000188:drug therapy* / Q000191:economics*; D054873:Dipeptidyl-Peptidase IV Inhibitors / Q000008:administration & dosage / Q000191:economics; D004359:Drug Therapy, Combination / Q000191:economics; D005260:Female; D006801:Humans; D007004:Hypoglycemic Agents / Q000008:administration & dosage / Q000191:economics; D008297:Male; D008687:Metformin / Q000008:administration & dosage / Q000191:economics* / Q000627:therapeutic use; D008875:Middle Aged; D018803:Models, Economic; D009570:Nitriles / Q000008:administration & dosage / Q000191:economics*; D011174:Portugal; D011446:Prospective Studies; D011759:Pyrrolidines / Q000008:administration & dosage / Q000191:economics*; D019057:Quality-Adjusted Life Years; D012307:Risk Factors; D013453:Sulfonylurea Compounds / Q000008:administration & dosage / Q000191:economics*; D000077597:Vildagliptin
D054873:Dipeptidyl-Peptidase IV Inhibitors; D007004:Hypoglycemic Agents; D009570:Nitriles; D011759:Pyrrolidines; D013453:Sulfonylurea Compounds; D008687:Metformin; D000077597:Vildagliptin; D000218:Adamantane
Cost-effectiveness; Diabetes mellitus; Metformin; Portugal; Sulphonylurea; Vildagliptin