To assess the cost-effectiveness of interleukin (IL)-17A inhibitor secukinumab vs the currently licensed biologic therapies in ankylosing spondylitis (AS) patients from a Canadian healthcare system perspective.
A decision analytic model (semi-Markov) evaluated the cost-effectiveness of secukinumab 150 mg compared to certolizumab pegol, adalimumab, golimumab, etanercept and etanercept biosimilar, and infliximab and infliximab biosimilar in a biologic-naïve population, over 60 years of time horizon (lifetime). The Bath Ankylosing Spondylitis Disease Activity Index (BASDAI 50) response rate was used to assess treatment response at week 12. Non-responders or patients discontinuing initial-line of biologic therapy were allowed to switch to subsequent-line biologics. Model input parameters (short-term and long-term changes in BASDAI and Bath Ankylosing Spondylitis Functional Index [BASFI], withdrawal rates, adverse events, costs, resource use, utilities, and disutilities) were obtained from clinical trials, published literature, and other Canadian sources. Benefits were expressed as quality-adjusted life years (QALYs). Cost and benefits were discounted with an annual discount rate of 1.5% for all treatments.
In the biologic-naïve population, secukinumab 150 mg dominated all comparators, as patients treated with secukinumab 150 mg achieved the highest QALYs (16.46) at the lowest cost (CAD 533,010) over a lifetime horizon vs comparators. In the deterministic sensitivity analysis, results were most sensitive to changes in baseline BASFI non-responders, BASDAI 50 at 3 months and discount rates. Probabilistic sensitivity analysis showed that secukinumab 150 mg demonstrated higher probability of achieving maximum net monetary benefit vs all comparators at various cost thresholds.
This analysis demonstrates that secukinumab 150 mg is the most cost-effective treatment option for biologic-naïve AS patients compared to certolizumab pegol, adalimumab, golimumab, etanercept and etanercept biosimilar, and infliximab and infliximab biosimilar for a lifetime horizon in Canada. Treatment with secukinumab translates into substantial benefits for patients and the healthcare system.