Background There are a few evidence on the dosage reduction of biological therapy in patients with axial Spondyloarthritis in clinical remission (1-4) and there are no studies on the factors that would predispose to relapse in these patients.
Objectives Our objective was to assess the differences in baseline characteristics between patients who relapsed and patients who remained in remission or low disease activity, LDA, at one year after dosage reduction of biological therapy in axial Spondyloarthritis.
Methods In a first phase we performed a prospective, observational study, of 12 months of follow-up, evaluating the percentage of patients who remained in clinical remission or LDA (BASDAI<4) and percentage of patients who relapsed (BASDAI≥4) at 12 months after dosage reduction of biological therapy in axial Spondyloarthritis according to an established protocol (Etanercept 50 mg every 10 days or 25 mg every week, Infliximab 3mg/kg every 8 weeks and Adalimumab 40 mg every 3 weeks).
In a second phase we assessed the differences in baseline characteristics between patients who relapsed and patients who remained in remission or LDA, at 12 months after dosage reduction of biological therapy.
Baseline characteristics analysed were: age, sex, number of: smokers, patients with Ankylosing Spondylitis diagnosis, HLAB27 positivity, peripheral involvement, previous uveitis, combined therapy with synthetic disease-modifying antirheumatic drugs (sDMARD), high CRP and ESR levels before biological therapy (CRP>0,6mg/dl and ESR>20mm/hour), with structural damage in spine, mean duration of clinical remission (months), mean duration of disease (years) and mean duration of biological treatment (months).
The differences in baseline characteristics between both groups of patients were evaluated by Student's t-test for quantitative variables and Chi-Square test for categorical variables.
Results - At 12 months of follow-up after dosage-reduction 76,2% of the patients remained in clinical remission or LDA (32) and 23,8% relapsed (10 patients).
- We detected a shorter duration of clinical remission, statistically significant, in the group of patients who relapsed comparing to the group who remained in clinical remission or LDA, at 12 months after dosage reduction of biological therapy (17,7±11,9 vs 30,6±18,9 months, p=0,049).
- We did not detect statistically significant differences in the other baseline characteristics between both groups of patients.
Conclusions When baseline characteristics between the group of patients with axial Spondyloarthritis who relapsed were compared to the group who remained in remission or LDA at one year after dosage reduction of biological therapy, a statistically significant shorter duration of remission was detected in the group of patients who relapsed and required the previous dose of treatment.
Navarro-Compán V. et al, Clin Rheumatol 2011;30:993-6.
Paccou J. et al, J Rheumatol 2012;39:1418-23.
De Stefano R. et al, Clin Rheumatol 2013 Sep 6.
Cantini F. et al, Biologics 2013;7:1-6.
Disclosure of Interest None declared