COST-EFFECTIVENESS ANALYSIS OF SECOND LINE TREATMENTFOR PATIENTS WITH ULCERATIVE COLITIS

De la Puente C,Hurtado V

Ministry of Health, Chile, Universidad de La Frontera,Universidad Pompeu Fabra, Barcelona.

OBJECTIVES: To evaluate the incremental cost-effectiveness ratio (ICER) of infliximab versus adalimumab and golimumab for second line treatment in adult patients diagnosed with moderate to severe ulcerative colitis with inadequate response or refractory to treatment with immunomodulators, in the Chilean context.

METHODS: A cost-effectiveness analysis based on a Markov model and a literature review of mathematical models for the pathology was conducted to inform the model structure.The Markov model comprised five health states:1.moderate to severe ulcerative colitis; 2.mild ulcerative colitis; 3.post-surgery; 4.specific death and 5.other causes of death. The effectiveness was expressed in quality adjusted life years (QALY), while the costs were expressed in Chilean pesos (CLP) 2017. A public health payer perspective and an undifferentiated discount rate for costs and effects of 3% were adopted. A cohort from age 18 to Chilean life expectancy 80 years old, was modelled. A probabilistic sensitivity analysis was performed for utility values, costs, transition probabilities and discount rates within a range of 0 and 6%.

RESULTS: The base case ICER for infliximab versus adalimumab was $59.751.286 CLP (USD 94.904) per quality adjusted life year (QALY) gained. Golimumab presented extended dominance. Only two parameters presented significant uncertainty:discount rate and cost of adalimumab, however it does not change the results.

CONCLUSIONS: Infliximab delivers more QALYs than adalimumab and golimumab, but it is not a cost-effective option. The ICER is above the cost-effectiveness threshold of 1 gross domestic product (GDP) per capita for 2017 in Chile. More long-term effectiveness studies are need it in order to decrease uncertainty of the Markov model results.