Michielsens CAJ, den Broeder N, Mulder MLM, et al. - Findings demonstrated T2T tapering of tumor necrosis factor inhibitor (TNFi) led to reduction of drug exposure and exerted no negative impacts on disease activity in psoriatic arthritis (PsA) and axial Spondyloarthritis (axSpA) patients relative to full dose continuation.

• This is a retrospective cohort analysis of PsA (n = 153) and axSpA (n = 171) patients doing well on TNFi and eligible for TNFi disease activity-guided dose optimization (DAGDO).

• Experts defined three different treatment spans: 1) full dose continuation period; 2) TNFi DAGDO period; 3) period with stable TNFi dose after DAGDO.

• A corrected difference in mean DAS28-CRP (Disease Activity Score 28-joint count C-reactive protein) was identified of 0.06 for the TNFi DAGDO period and 0.03 for the period with stable TNFi dose, vs full dose continuation span.

• For Bath Ankylosing Spondylitis Disease Activity Index, differences were 0.03 and 0.05 respectively.

• For the three treatment spans, the mean %DDD (mean percentage of the Daily Defined Dose) was for PsA 108%, 62% and 78%, and for axSpA 108%, 62%, and 72% respectively.