Switching from an anti-TNF monoclonal antibody to soluble TNF-receptor yields better results than vice versa: An observational retrospective study of 72 rheumatoid arthritis switchers.

Objectives: To evaluate the benefits for rheumatoid arthritis (RA) patients of switching from one tumor necrosis factor inhibitor (TNFi) to another based on reason for change (primary failure, escape or intolerance) and molecule-switching order.

Methods: Between 2000 and 2008, 356 RA patients prescribed a TNFi (infliximab [IFX], etanercept [ETA] or adalimumab [ADA]) and undergoing standardized evaluation were included in this retrospective study. Detailed demographic, clinical and biological data were collected before first biologic use and ≤6 months later to evaluate response based on EULAR-criteria. Primary failure, escape or intolerance of first TNFi triggered switch to another TNFi, the response of which was evaluated 6 months later. Propensity score then measured any interaction with baseline variables.

Results: Of the 356 RA patients, 38 switched from IFX/ADA to ETA, 26 from ETA to IFX/ADA, and eight from one monoclonal antibody (mAb; IFX/ADA) to another. Clinical parameters for switchers and non-switchers were comparable. Switchers changed therapies because of primary failure (36.1%), escape (33.3%), or intolerance (30.6%), with no difference found in these subgroups. More switchers responded to the second TNFi than the first (P<0.01), respectively, regardless of switch (ETA to IFX/ADA: 50 vs. 23.1% [P<0.05]; IFX/ADA to ETA: 57.9 vs. 15.8% [P<0.001]) or reason for changing. In addition, DAS28 decreased more with the second antagonist (P<0.001) and regardless of molecules switched (P<0.01). Survival of the second TNFi was significantly longer with switch from mAb to the soluble receptor than vice versa (P<0.05).

Discussion: Overall, any switching from one TNFi to another, especially mAb to soluble receptor, was often beneficial for RA patients.