The Cost-effectiveness of Initial Immunomodulators or Infliximab Using Modern Optimization Strategies for Crohn's Disease in the Biosimilar Era.

BACKGROUND: Treatment cost, efficacy, and safety are integral considerations when optimizing management of Crohn's disease (CD). This study assessed the cost-effectiveness of initial immunomodulator and anti-tumor necrosis factor (anti-TNF) agents for the treatment of CD from a US third-party perspective, incorporating current treatment algorithms, optimization strategies, and reduced costs availed by biosimilars. METHOD: A 1-year Markov model was developed to simulate the cost and quality-adjusted life-years (QALYs) of initial azathioprine, infliximab, and combination therapy for moderate to severe CD. Treatment was changed based on tolerability and clinical disease activity at 3-monthly intervals. Efficacy data were based on published literature. RESULTS: Initial azathioprine had the lowest cost and utility ($35,337 and 0.63 QALYs), whereas combination therapy was the costliest yet conferred the highest health benefits ($57,638 and 0.67 QALYs). The incremental cost-effectiveness of infliximab and combination therapy compared with azathioprine were both in excess of $500,000 per QALY gained. Initial azathioprine remained the most cost-effective treatment on sensitivity analysis compared with infliximab and combination therapy, with 90% reductions in anti-TNF therapy costs and a 5-year time horizon, although combination therapy had an acceptable cost-effectiveness when costs were reduced in the extended model. Initial infliximab, ustekinumab, and vedolizumab were dominated by combination therapy. CONCLUSIONS: In the biosimilar era, initial azathioprine with escalation to infliximab appeared more cost-effective in the short term compared with infliximab or combination therapy, although initial combination therapy yields acceptable ICERs in the long term with continued reductions in anti-TNF therapy costs and will likely be the preferred treatment strategy in the future.