- Fecal Incontinence
|Proactive Vs Reactive Therapeutic Drug Monitoring of Infliximab in Crohn
Negoescu DM1, Enns EA2, Swanhorst B1, Baumgartner B1, Campbell JP3, Osterman MT4, Papamichael K5, Cheifetz AS5, Vaughn BP3. Inflamm Bowel Dis. 2019 Jun 10. pii: izz113. doi: 10.1093/ibd/izz113. [Epub ahead of print]
1 Department of Industrial and Systems Engineering, University of Minnesota College of Science and Engineering, Minneapolis, MN.
2 Division of Health Policy and Management, University of Minnesota School of Public Health, Minneapolis, MN.
3 Division of Gastroenterology, Hepatology and Nutrition, University of Minnesota Medical School, Minneapolis, MN.
4 Division of Gastroenterology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA.
5 Center for Inflammatory Bowel Disease, Beth-Israel Deaconess Medical Center, Harvard Medical School, Boston, MA.
BACKGROUND: Therapeutic drug monitoring (TDM) is increasingly performed for Infliximab (IFX) in patients with Crohn's disease(CD). Reactive TDM is a cost-effective strategy to empiric IFX dose escalation. The cost-effectiveness of proactive TDM is unknown. The aim of this study is to assess the cost-effectiveness of proactive vs reactive TDM in a simulated population of CD patients on IFX.
METHODS: We developed a stochastic simulation model of CD patients on IFX and evaluated the expected health costs and outcomes of a proactive TDM strategy compared with a reactive strategy. The proactive strategy measured IFX concentration and antibody status every 6 months, or at the time of a flare, and dosed IFX to a therapeutic window. The reactive strategy only did so at the time of a flare.
RESULTS: The proactive strategy led to fewer flares than the reactive strategy. More patients stayed on IFX in the proactive vs reactive strategy (63.4% vs 58.8% at year 5). From a health sector perspective, a proactive strategy was marginally cost-effective compared with a reactive strategy (incremental cost-effectiveness ratio of $146,494 per quality-adjusted life year), assuming a 40% of the wholesale price of IFX. The results were most sensitive to risk of flaring with a low IFX concentration and the cost of IFX.
CONCLUSIONS: Assuming 40% of the average wholesale acquisition cost of biologic therapies, proactive TDM for IFX is marginally cost-effective compared with a reactive TDM strategy. As the cost of infliximab decreases, a proactive monitoring strategy is more cost-effective.