De novo manifestations during adalimumab treatment in Behçet's syndrome.

Objectives: Treatment response may be variable across organ manifestations of Behçet's syndrome (BS). We aimed to determine the frequency of de novo manifestations during adalimumab treatment.

Methods: We conducted a chart review of all BS patients who received adalimumab in our centre between 2008 and 2023. Demographic data, reasons for initiating adalimumab, concurrent medications, previous treatments, and outcomes were recorded. We defined de novo manifestations as new BS manifestations that occurred for the first time during treatment with adalimumab. For patients with vascular involvement, a new vascular event at another vessel was also considered as a de novo manifestation.

Results: Among the 335 patients, a de novo manifestation developed in 14 (4%) patients. De novo manifestations were vascular involvement in five patients, arthritis in three, anterior uveitis in two, nervous system involvement in two, gastrointestinal involvement in one, and epididymitis in one patient. The primary reasons for adalimumab treatment were vascular involvement in five patients, uveitis in four, arthritis in three, mucocutaneous involvement in one, and epididymitis in one patient. Upon the development of de novo manifestation, adalimumab was switched to another biologic in four patients, dose was intensified in three, colchicine, conventional immunosuppressives and/or glucocorticoids were added in five, and topical eye drops were added in two patients, leading to remission of de novo manifestations in all patients.

Conclusion: De novo manifestations were infrequent (4%) among BS patients treated with adalimumab. Of these, 57% were major organ involvement, mainly vascular involvement. None of the patients developed posterior uveitis.