OBJECTIVES: To evaluate the cost-effectiveness of Secukinumab (SEC), a fully human monoclonal antibody that selectively neutralizes interleukin (IL)17A, versus currently licensed biologic therapies in patients with Ankylosing Spondylitis (AS) from a Canadian healthcare system perspective.
METHODS: A decision analytic semi-Markov model evaluated the cost-effectiveness of SEC 150mg compared to adalimumab (ADA), certolizumab pegol (CER P), etanercept (ETN), ETN biosimilar, golimumab (GOL), infliximab (INF), and INF biosimilar in a biologic-naïve population and a mixed population of biologic-naïve and experienced patients, over a lifetime horizon (60 years). The response to treatments was evaluated at week 12 by Bath AS Disease Activity Index (BASDAI 50) response rates. Non-responders or patients discontinuing initial-line of biologic therapy were allowed to switch to subsequent-line biologics. Model input parameters (short term changes in BASDAI, short- and long-term changes in Bath AS Functional Index (BASFI), withdrawal rates, adverse events, costs, resource use, utilities, and disutilities) were collected from clinical trials, published literature, and other Canadian sources. Benefits were expressed as quality-adjusted life-years (QALYs). Costs were reported in 2016 Canadian dollars (CAD). An annual discount rate of 1.5% was applied to costs and benefits.
RESULTS: In the biologic-naïve population, SEC dominated all therapies. Patients treated with SEC achieved the most QALYs (16.09) at the lowest cost (CAD 1,106,529) over a lifetime horizon compared to all other drugs. Similarly, in the mixed population biologic-naïve and biologic experienced), SEC dominated all treatments as it generated more QALYs (14.59) at lower costs (CAD 1,141,452). Across all comparators, deterministic sensitivity analyses indicated that the results were most sensitive to variation in BASDAI 50 response, change in BASFI score, and withdrawal rates.
CONCLUSIONS: SEC is dominant versus all licensed biologics and INF, ETN biosimilars for the treatment of active AS in biologic-naïve and mixed populations in Canada.
