Background Two phase 3 clinical trials, MEASURE 1 and 2, demonstrated the efficacy of secukinumab for active ankylosing spondylitis (AS). However, there is limited data comparing the efficacy of secukinumab with established AS treatments.
Objectives The objective of this study was to compare relative efficacy between adalimumab and secukinumab, estimate the number needed to treat (NNT), and evaluate the incremental cost per responder (CPR) for the treatment of active AS.
Methods An indirect comparison was conducted using individual patient data from the adalimumab clinical trial (ATLAS)1 and published data from the secukinumab trials (MEASURE 1 and 2).2 Only dosages approved by the European Medicines Agency (adalimumab 40mg and secukinumab 150mg) were included in the analysis. To adjust for the cross-trial differences, individual patients in ATLAS were re-weighted to match the mean baseline characteristics in the MEASURE trials.3,4 Specifically, age, weight, gender, duration of AS, baseline methotrexate use, baseline sulfasalazine use, presence of positive HLA-B27, BASDAI score and total back pain score were included in the baseline matching. The ASAS20, ASAS40 and ASAS 5/6 response rates relative to placebo at the end of the trial period (adalimumab: 12 weeks, secukinumab: 16 weeks) were compared. NNTs to achieve one additional ASAS20, ASAS40 and ASAS 5/6 responder and the corresponding incremental CPRs were also calculated. Drug costs in terms of 2015 Euros were obtained from the Lauer Taxe.5
Results After matching, mean baseline characteristics were balanced across the ATLAS and MEASURE 1 and 2 populations. Compared to secukinumab (n=197), adalimumab (n=204) demonstrated similar efficacy in ASAS20/40 and ASAS 5/6. The mean differences (95% confidence interval) between adalimumab and secukinumab in relative ASAS20, ASAS40 and ASAS 5/6 response rates were 2.3% (-12.8%, 17.5%), -0.4% (-14.1%, 13.4%), and -3.1% (-17.3%, 11.2%), respectively. The NNTs to achieve one additional responder were also comparable between adalimumab and secukinumab: 2.9 vs 3.1 in ASAS20, 3.7 vs 3.7 in ASAS40, and 3.1 vs 2.8 in ASAS 5/6. Incremental CPRs relative to placebo were lower for adalimumab compared to secukinumab across all efficacy measures (Figure 1).
Conclusions In the absence of head to head trials comparing adalimumab and secukinumab, the current indirect comparison reduced cross-trial differences and provides timely and reliable evidence for physicians and payers. After adjusting for cross-trial differences in baseline characteristics, adalimumab demonstrated similar efficacy as secukinumab in terms of ASAS20, ASAS40 and ASAS 5/6 responses and was associated with lower incremental CPR compared with secukinumab over the trial period among patients with active AS.
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http://www.lauer-fischer.de.Accessed December 2015.
Disclosure of Interest K. Betts Consultant for: AbbVie, M. Mittal Shareholder of: AbbVie, Employee of: AbbVie, J. Song Consultant for: AbbVie, M. Skup Shareholder of: AbbVie, Employee of: AbbVie, A. Joshi Shareholder of: AbbVie, Employee of: AbbVie