Cost–utility analysis of second-line therapy with rituximab compared to tumour necrosis factor inhibitors in rheumatoid arthritis

Abstract

Objective

To compare direct costs and treatment utility associated with the second-line therapy with rituximab and tumour necrosis factor inhibitors (TNFis) (adalimumab, etanercept, and infliximab) in patients with Rheumatoid Arthritis (RA) using data from a prospective registry.

Methods

Health Assessment Questionnaire Disability Index (HAQ-DI) scores and RA-related healthcare resource utilization data (biologic agents and visits to rheumatologists) were extracted from a registry (Quebec, Canada) for patients with RA (n = 129) who had to discontinue a first-line TNFi and were treated with rituximab, adalimumab, etanercept, or infliximab as the second-line therapy between January 2007 and May 2016. A decision analytic model followed patients for 1 and 6 years. Treatment utility was measured as quality-adjusted life-years (QALYs) gained, which were calculated from HAQ-DI scores observed over the follow-up time. Quebec 2020 unit costs (Canadian Dollars, $) were used to value healthcare resource consumption. A probabilistic sensitivity analysis was performed with 10,000 Monte Carlo simulations to assess uncertainty around point-estimates of cost-utility.

Results

Over 1-year, rituximab and etanercept resulted in the effectiveness of 0.80 QALYs gained at the cost of $14,291and $18,880, respectively, and were dominant (i.e. associated with lower costs and more QALYs gained) compared to adalimumab (0.79 QALYs, $18,825) and infliximab (0.76 QALYs, $20,158). Over 6-years, rituximab (4.42 QALYs, $82,402) was dominant compared to adalimumab (4.30 QALYs, $101,420), etanercept (4.02 QALYs, $99,191), and infliximab (3.71 QALYs, $100,396). In the probabilistic analysis, rituximab was dominant over adalimumab, etanercept, and infliximab with the probability of 0.51, 0.62, and 0.65, respectively.

Conclusion

Real-world data revealed differences between alternative biologic agents used as the second-line therapy in terms of both treatment costs for the healthcare system and utility of treatment for patients. Therefore, new guidelines on the order of selecting and switching biologic agents should be explored.

Keywords:

• Arthritis;
• rheumatoid;
• economics;
• pharmaceutical;
• biological therapy;
• registries

Transparency

Declaration of funding

This is no funding to declare for this study. RHUMADATA receives yearly unrestricted operational grants from AbbVie Canada, Amgen Canada, Eli Lilly Canada, Gilead, Novartis Canada, Pfizer Canada, Sandoz Canada, and Sanofi Canada.

Declaration of financial/other relationships

Authors declare no financial supporter(s) of the study and no financial support or other benefits from commercial sources for the work reported on in the manuscript, or any other financial interests that any of the authors may have, which could create a potential conflict of interest or the appearance of a conflict of interest with regard to the work. Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Ethical approval

The authors have obtained the required ethical approvals –ethics approval for the study was received from the Conjoint Health Research Ethics Board at the University of Calgary (REB16-0831). The authors have given necessary attention to ensure the integrity of the work and agree to bear the applicable publication charges if their manuscript is accepted for publication.