Background/Purpose: Secukinumab (SEC) and adalimumab (ADA) are approved for the treatment of patients with active AS. However, there are no head-to-head randomized controlled trials (RCTs) between SEC and ADA. In the absence of such trials, matching-adjusted indirect comparison (MAIC) can be used to generate comparative effectiveness data. MAIC adjusts for differences in baseline patient characteristics by using individual patient data (IPD) from trials of one treatment to match the population of a different therapy arm of another trial. The aim of this MAIC was to assess the relative effectiveness of SEC 150 mg and ADA 40 mg in patients with active AS.     

Methods: IPD from the pooled SEC 150 mg arms of MEASURE 1 (n=125) and MEASURE 2 (n = 72) were weighted to match the published baseline characteristics of the ADA 40 mg arm of ATLAS (n = 208); placebo arms were also matched. Logistic regression was used to determine weights for age, sex, BASFI, CRP and previous anti-TNF therapy. Recalculated SEC 150 mg outcomes (effective sample size [ESS] = 120; placebo ESS = 120) were compared with published aggregated ADA data at weeks 12, 16, 24 and 52. Placebo-adjusted results were valid only until week 12 as patients receiving placebo in ATLAS could switch to open label ADA (69% had switched by week 24). Therefore, all comparisons beyond week 12 were non-placebo adjusted. Imputation methods for missing data were matched between trials. NRI was available for all binary outcome data except for ADA at week 52 which was LOCF only and included placebo switchers. This was matched by including placebo switchers for SEC at week 52. Comparisons are presented as response rate (%) and pairwise comparisons using odds ratios (ORs).

Results: At week 12 there were no differences in placebo-adjusted response rates between SEC and ADA. At week 16, there was a higher ASAS 20 non-placebo adjusted response rate for SEC relative to ADA (OR [95% CI]: 1.60 [1.01–2.54], p = 0.047). At week 24, there were higher ASAS 20 and ASAS 40 non-placebo adjusted response rates for SEC relative to ADA (OR [95% CI]: 1.76 [1.11–2.79], p = 0.017 and OR [95% CI]: 1.79 [1.14–2.82], p = 0.012, respectively). At week 52, there were higher ASAS 20 and ASAS 40 non-placebo adjusted response rates for SEC relative to ADA (OR [95% CI]: 1.48 [0.98–2.22], p = 0.062 and OR [95% CI]: 1.54 [1.06–2.23], p = 0.023, respectively). A sensitivity analysis that included BASDAI score in the baseline matching showed similar findings.

Conclusion: This MAIC showed that SEC 150 mg was associated with higher (non-placebo-adjusted) ASAS 20 response rates at weeks 16, 24 and 52 and ASAS 40 at weeks 24 and 52 relative to ADA. No differences in placebo-adjusted response rates were evident at week 12. Substantial switching of placebo patients to active therapy in ATLAS precluded analysis of placebo-adjusted data beyond week 12. This exploratory analysis requires confirmation by a head-to-head RCT.

MAIC ASAS 20 and ASAS 40 response rates at weeks 12, 24 and 52