Abstract
BACKGROUND: Adalimumab, an anti-TNF-α biologic agent, has emerged as a principal treatment option for patients with non-infectious uveitis. The influence of adalimumab anti-drug antibodies (AAA) on the efficacy of adalimumab therapy is not yet fully understood. We aim to understand their clinical implications in the context of therapeutic drug monitoring and the factors contributing to the formation of these antibodies. METHODS: We conducted a retrospective analysis of 114 patients with non-infectious uveitis who developed AAA while undergoing adalimumab therapy. RESULTS: Among the 114 AAA-positive uveitis patients, a significant correlation was observed between AAA levels and reduced adalimumab serum levels (r = -0.58, p < 0.001). The mean time to AAA detection was 2.1 years (range 0.1-11.9 years), with 45.6% of cases identified through routine testing. If AAA levels were initially low, subsequent measurements for AAA were more likely to become negative during treatment (r = 0.63, p < 0.001). Higher AAA concentrations were associated with a shorter time to detection (r = -0.27, p = 0.01) and younger age (r = -0.21, p = 0.03). There was a trend, though no significant influence, of concomitant immunosuppression with prednisolone ≤ 7.5 mg or methotrexate on antibody formation (p = 0.18). No significant difference was observed in AAA levels between uveitis subtypes. CONCLUSIONS: Higher AAA concentrations are associated with lower adalimumab serum levels in uveitis patients. Routine clinical testing is essential for optimal therapeutic drug monitoring to prevent early loss of effectiveness.