Tapering versus steady-state methotrexate in combination with tocilizumab for rheumatoid arthritis: a randomized, double-blind trial

Objective. To explore whether tocilizumab + tapering MTX has comparable efficacy and safety vs tocilizumab + stable MTX in adult RA patients with inadequate response to MTX. Methods. This randomized, placebo-controlled non-inferiority study involved patients with severe active RA [28-joint DAS (DAS28) >5.1] who had initiated tocilizumab + MTX at the study start. Patients received open-label tocilizumab (8 mg/kg i.v. every 4 weeks) and open-label MTX. At week 24, patients achieving good/moderate EULAR response were randomized to group A (double-blind MTX taper) or group B (double-blind MTX maintenance); both arms continued open-label tocilizumab. Primary analysis was the proportion of patients maintaining good/moderate EULAR response from week 24 to 60. Results. The study stopped early due to low recruitment, although the predetermined non-inferiority criteria were still met; 427 patients were enrolled to the open-label phase at week 0. At week 24, EULAR good/moderate response was achieved in 272 individuals (64.4%) who were randomized, 136 in each arm (36% withdrew/were not eligible). Additionally, 45.0% achieved DAS28 43.2, 33.5% achieved remission (DAS28 <2.6) and 64.2% had a DAS28 change 51.2. After week 24 randomization, the proportion of patients maintaining good/moderate EULAR response to week 60 was significantly greater for MTX taper vs stable MTX (76.5 vs 65.4%; P = 0.036), and since the lower limit of the 95% CI was >0.9, the pre-determined criteria for non-inferiority was fulfilled despite reduced recruitment. Safety analysis revealed no unexpected tocilizumab safety signals. Conclusions. Tapering MTX in patients with RA receiving tocilizumab was non-inferior to continuing stable MTX in maintaining a good/moderate EULAR response. There were no unexpected safety signals; tocilizumab and MTX therapy was generally well tolerated in both groups.