Background Tumour necrosis factor (TNF) blockade is highly effective for the treatment of spondyloarthritis (SpA). Unfortunately, in axial SpA, anti-TNF therapy discontinuation leads to fast disease relapse in almost all patients. However, what happens upon discontinuation of anti-TNF therapy in peripheral SpA remains unknown.

Objectives The aim of this study was to assess persistent remission versus relapses after anti-TNF therapy discontinuation in peripheral SpA.

Methods Twenty six adalimumab-treated patients with peripheral SpA not fulfilling the criteria for ankylosing spondylitis or psoriatic arthritis¹ were included in this study. Patients had received either 12 (n=12) or 24 weeks (n=14) of adalimumab treatment before discontinuation of the anti-TNF therapy. After discontinuation patients were prospectively followed for 16 weeks and seen for a relapse visit upon worsening of symptoms. Relapse was defined as increase of ≥1 swollen joint, or ≥2 points in patient’s or physician’s global assessment of disease activity or Bath Ankylosing Spondylitis Disease Activity Index (BASDAI).

Results At baseline (defined as the moment of interruption of adalimumab), disease activity scores were low (Table 1). Eleven patients (42%)had reached a 66 swollen joint count (SJC66) of zero and 14patients(54%) an Ankylosing Spondylitis Disease Activity Score (ASDAS) inactive disease. After anti-TNF treatment discontinuation there was a significant increase in all disease activity parameters (Table 1). Nineteen patients (73%) experienced a relapse with a mean time to relapse of 10.0±3.2 weeks. Moreover, only 4 patients (16%) maintained a SJC66 of zero or ASDAS inactive disease over 16 weeks. Univariate analysis did not identify parameters (including treatment duration prior to discontinuation, disease activity parameters, and demographic or clinical characteristics) to be significantly associated with the occurrence of relapse. However, the time to relapse correlated with the duration of adalimumab treatment (R=0.722, p<0.001 by Pearson correlation test) and a low SJC66 at baseline (R= –0.585, p=0.002).

Conclusions More than 70% of the peripheral SpA patients show a rapid relapse within 16 weeks after interruption of successful TNF blockade.

References

1. Paramarta JE, De Rycke L, Heijda TF, et al. Efficacy and safety of adalimumab for the treatment of peripheral arthritis in spondyloarthritis patients without ankylosing spondylitis or psoriatic arthritis. Ann Rheum Dis 2012 [Epub ahead of print]

Disclosure of Interest None Declared