Certolizumab Pegol Compared to Natalizumab in Patients with Moderate to Severe Crohn's Disease: Results of a Decision Analysis

A significant proportion of patients with Crohn's disease (CD) lose response to antibodies directed against tumor necrosis factor alpha (TNF). Prior TNF-antagonist failure is associated with lower rates of response to subsequent TNF-antagonist therapy. In patients failing two anti-TNF agents, a choice exists between using a third-anti-TNF therapy or natalizumab (NAT), an alpha-4 integrin inhibitor. A cost-effectiveness analysis comparing these competing strategies has not been performed. A decision analytic model was constructed to compare the performance of certolizumab pegol (CZP) versus NAT in patients with moderate to severe CD. Previously published estimates of efficacy of third-line anti-TNF therapy and NAT were used to inform the model. Costs were expressed in 2010 US dollars. A 1-year time frame was used for the analysis. In the base case estimate, use of NAT was only marginally more effective [0.71 vs. 0.70 quality adjusted life-years (QALYs)] than CZP but was expensive with an incremental cost-effectiveness ratio (ICER) of $381,678 per QALY gained. For CZP 2 months response rate of at least 24%, NAT had an ICER above the willingness-to-pay (WTP) threshold. The model was sensitive to the costs of both therapies; for all CZP costs below $2,300 per dose, NAT had higher ICER than the WTP threshold. Substituting adalimumab for CZP resulted in similar ICER estimates and thresholds for NAT use. In patients with moderate to severe CD failing two TNF-antagonists, using a third TNF-antagonist therapy appears to be a cost-effective strategy without significantly compromising treatment efficacy.