Effect of biologic disease-modifying anti-rheumatic drugs targeting remission in axial spondyloarthritis: systematic review and meta-analysis

Objectives: To assess the efficacy of biologic DMARDs (bDMARDs) in achieving Assessment of Spondyloarthritis International Society partial remission (ASAS-PR) and/or Ankylosing Spondylitis Disease Activity Score inactive disease (ASDAS-ID), as remission-like surrogates, in axial SpA (axSpA).

Methods: Data from randomized controlled trials (RCTs), including long-term extensions, were included. A systematic literature review was performed using the MEDLINE database (first search May 2018, updated February 2020) and PICO criteria according to Patients-adults with radiographic or non-radiographic axSpA; Intervention-any bDMARD; Comparator-placebo and/or any different drug; Outcomes-ASAS-PR and/or ASDAS-ID as primary or secondary endpoints. Meta-analysis was performed after assessment of the homogeneity of study designs, populations and outcomes.

Results: After screening 155 references, a total of 22 RCTs and 28 long-term extensions were retrieved. ASAS-PR was the dominant remission-like definition used. Concerning TNF inhibitors, 14/17 RCTs provided evidence of efficacy in reaching remission at different time points: 12, 16, 24 and 28 weeks (ASAS-PR in 16-62% of patients and ASDAS-ID in 24-40% of patients). With a limited number of studies available, IL-17A inhibitors exhibited remission rates of 15-21% for ASAS-PR and 11-16% for ASDAS-ID at week 16. A meta-analysis regarding ASAS-PR was performed considering RCTs with a similar duration (12, 16 or 24 weeks). The relative risk for achieving remission was 3.864 (95% CI 2.937, 5.085).

Conclusion: bDMARDs have a clear impact in axSpA remission evaluated by ASAS-PR. Nevertheless, these data show an unmet need for improved reporting of remission-like outcomes.