Potential for sustaining remission in ankylosing spondylitis patients upon netakimab discontinuation

Abstract

Introduction. Biological disease modifying drugs (bDMARD) in the treatment of ankylosing spondylitis (AS) have shown good results with the achievement and long-term preservation of remission. There is a discussion about the withdrawal of drugs without loss of effect in order to reduce the economic burden, drug load, adverse events, the possibility of interrupting therapy during surgical treatment.Aim. To evaluate the potential for sustaining the therapeutic effect of netakimab (NTK) after its discontinuation in patients with AS who have achieved remission.Materials and methods. A cohort of 11 patients diagnosed with ankylosing spondylitis (AS) who had achieved remission was included in this study. The patients were closely observed for 52 weeks after discontinuing NTK treatment. AS exacerbations, pain intensity, disease activity scores (BASDAI, ASDAS), enthesitis evaluations (MASES), functional impairments (BASMI and BASFI), C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) levels were documented, as well as radiographic and MRI assessments of the sacroiliac joints and spine were performed.Results. Out of the 11 patients, 5 (45.5%) experienced AS exacerbations within the 12-month observation period. Patients who developed flare-ups had higher baseline levels of BASDAI, ASDAS, BASMI, and CRP at the time of NTK discontinuation. They also had a longer disease duration and were older compared to patients without relapse (p < 0.05). The presence of flare-ups was significantly associated (p < 0.05) with a history of peripheral arthritis, previous treatment with IFN-alpha, and the number of comorbidities. By week 52 of the observation period, patients demonstrated a deterioration in both activity and functional limitations (p < 0.05). Elevated ASDAS-CRP levels were found to be correlated (p < 0.05) with higher radiographic stages of sacroiliitis, the presence of syndesmophytes, functional limitations based on BASMI at the time of drug discontinuation, and the absence of continuous NSAID use. Significant prolongation of remission was associated with a substantial decline in ASDAS-CRP under NTK treatment (rSp = 0.996; p < 0.05), especially among younger patients (rSp = 0.607; p < 0.05).Conclusions. Approximately half of the patients who discontinued NTK therapy after achieving clinical and laboratory remission were able to sustain it. Maintenance of remission for 1 year was more prevalent in younger patients with shorter duration of AS, achieving inactive disease status based on ASDAS-CRP, fewer functional limitations, absence of peripheral arthritis, and comorbidities. Nevertheless, regular patient monitoring is necessary to promptly identify disease recurrence.