Background The effectiveness of anti-tumor necrosis factor -alpha therapy (anti-TNF-α) is well known, but the discontinuation of this therapy is insufficiently studied.
Objectives To analyze consequences and safety of anti-TNF-α therapy after discontinuation in patients with ankylosing spondylitis (AS).
Methods 79 patients with AS were included in the research: 72 with axial AS and 7 with peripheral AS. All these patients discontinued anti-TNF-α therapy from 1 week to 54 weeks. The age of patients was from 18 years to 75 years. There were 74% men and 26% women. The remission was from 2 weeks to 6,5 years. The duration of current biological therapy was from 14 weeks to 9 years. The duration of disease was from 3 years to 46 years. 37 patients (86%) were HLA B27-positive and 6 patients (14%) HLA B27-negative among those who had done this test.
The following criteria were used for assessment of disease activity in the result of anti-TNF-α therapy discontinuation: BASFI, BASDAI, DFI, VAS, CRP, ESR. Clinical relapse was defined as: BASDAI≥4, BASFI≥4, DFI≥4, VAS≥6, increase in CRP and ESR.
Results The vast majority of patients who discontinued the anti-TNF-α therapy had clinical relapse. The mean time of relapse after the discontinuation of biological therapy was 14,1±12,2 weeks (p<0.05) for patients with axial AS and 8,5±4,6 weeks (p<0.05) for patients with peripheral AS. Relapse developed slower among patients who had a long remission. Patients with frequent discontinuations (4 and 5 times) were accompanied by faster developing of relapse in every subsequent break. There was only one patient with axial AS who continued to be in remission after long discontinuation (54 weeks). He was HLA B27 – positive, the duration of disease was 20 years, the duration of biological therapy by etanercept was 2,75 years.
There is the correlation between the duration of biological therapy's discontinuation and developing of relapse. Longer the break is, worse indexes BASDAI, BASFI, DFI, VAS, ESR and CRP indicators are.
83% patients who had uveitis after discontinuation of biological therapy had relapse in uveitis, 17% patients hadn't.
Conclusions The interruption of anti-TNF-α therapy in patients with ankylosing spondylitis is unsafe and in the majority of cases leads to clinical relapse. AS-therapy must be permanent and uninterrupted.
Disclosure of Interest None declared