Minimum effective dosages of anti-TNF in rheumatoid arthritis: a cross-sectional study.

Objective: To evaluate the modified dosages of anti-TNF in controlling disease activity in rheumatoid arthritis (RA) measured by DAS28-ESR.

Methods: Cross-sectional study: RA patients treated with etanercept (ETN), adalimumab (ADA) or infliximab (IFX), at standard or modified doses. Methods: dosage, concomitant disease modifying drugs (DMARDs), DAS28-ESR.

Results: 195 RA patients included (79% women, mean age 58.1 years): ETN=81, ADA=56, IFX=58. Mean disease duration and time to first biological treatment was higher in IFX group (P=.01). Patients distribution by dosage: standard: ETN (72.8%), ADA (69.6%), IFX (27.6%); escalated: IFX (69%), ADA (5.4%), ETN (0%); reduced: ETN (27.1%), ADA (25%), IFX (3.4%). Concomitant DMARDs use was lower in ETN (58.2%) than ADA (66.07%) and IFX (79.31%). Higher proportion of responders (DAS28 ≤3.2) in ADA (65.3%) and ETN (61.7%) than IFX (48.3%).

Conclusions: RA clinical control can be preserved with modified anti-TNF dosages. Controlled prospective studies should be performed to define when therapy can be tailored and for which patients.