Mo1331 The Cost-Effectiveness of Infliximab Is Different in Ulcerative Colitis and Crohn's Disease: Markov Model in a Population-Based Incident Patient Cohort

Abstract

BACKGROUND: Biologic drugs were shown to improve patient outcomes in inflammatory bowel diseases. Despite their known ability to reduce hospital admissions and surgery, these savings may not be sufficient to offset their high acquisition price, as was shown in several mathematical models. We sought to investigate the impact of infliximab (IFX) on healthcare costs and quality-adjusted life-expectancy in a real-world patient cohort. AIM: To determine direct healthcare costs, quality-adjusted life years (QALYs) and incremental cost-effectiveness ratios (ICERs) of IFX given in UC and CD as episodic (on demand) therapy or as 1 year or 10 year maintenance treatment. METHODS: The patients comprised a pre-IFX-era, population-based, multi-national incident cohort of ulcerative colitis (UC) and Crohn's disease (CD). The patients had received standard (non-biologic) treatment for 10 years and their economic data and transition states were reported (Gastroenterology 131: 719, Aliment Pharmacol Ther 31: 735) The cohort was modeled in a Markov analysis with a 10 year horizon to allow patients to receive IFX whenever entering corticosteroid-immunomodulator-resistant or need-for-surgery transition states, by current clinical criteria. Costs, QALYs and ICERs were computed. Each patient was run in all 4 arms of the study: standard therapy, episodic IFX, 1 y maintenance IFX and 10 y maintenance IFX; the data were compared. In a scenario analysis IFX base-price of 100% was reduced to 80% and 50%; decay rate of IFX use was varied as 20%, 50% and 80%. RESULTS: There were 339 UC (mean age at onset 40.5 ± 14.8 years, 50.4% male) and 212 CD (34.4 ± 14.5 y, 49.9% male) patients in the study. CD patients had about double the costs, but lower QALYs, than UC (Table 1). A longer maintenance period engendered higher cost, but increased the QALYs. Episodic IFX treatment improved QALY's and had lower costs than standard therapy in UC and CD, and was thus dominant. In UC, I y maintenance IFX dominated episodic therapy (Table 2), but 10 y maintenance was not cost-effective except when the drug acquisition price was lowered to 50%. In CD, maintenance IFX (1 y and 10 y) produced ICERs in the range 486,806 to 48,120 Euros/QALY gained. The 10 y ICERs were lowest but still not costeffective. The price of IFX was the principal determinant of cost of treatment and magnitude of the ICERs even when the rate of decay was raised to 50% and 80%. CONCLUSIONS. In our model, standard therapy had higher costs and less favorable patient outcomes and was dominated by episodic IFX in both diseases. At current drug prices, maintenance IFX in CD patients did not provide good value for money when compared with episodic therapy, but was dominant over episodic therapy in UC when restricted to 1 year of treatment. Table 1. Mean 10 y costs and QALYs per patient