IMPORTANCE One-third of patients with rheumatoid arthritis show inadequate response to tumor necrosis factor α (TNF-α) inhibitors; little guidance on choosing the next treatment exists. OBJECTIVE To compare the efficacy of a non-TNF-targeted biologic (non-TNF) vs a second anti-TNF drug for patients with insufficient response to a TNF inhibitor. DESIGN, SETTING, AND PARTICIPANTS A total of 300 patients (conducted between 2009-2012) with rheumatoid arthritis, with persistent disease activity (disease activity score in 28 joints-erythrocyte sedimentation rate [DAS28-ESR] Ն 3.2 [range, 0-9.3]) and an insufficient response to anti-TNF therapy were included in a 52-week multicenter, pragmatic, open-label randomized clinical trial. The final follow-up date was in August 2013. INTERVENTIONS Patients were randomly assigned (1:1) to receive a non-TNF-targeted biologic agent or an anti-TNF that differed from their previous treatment. The choice of the biologic prescribed within each randomized group was left to the treating clinician. MAIN OUTCOMES AND MEASURES The primary outcome was the proportion of patients with good or moderate response according to the European League Against Rheumatism (EULAR) scale at week 24. Secondary outcomes included the EULAR response at weeks 12 and 52; at weeks 12, 24, and 52; DAS28ESR, low disease activity (DAS28 Յ3.2), remission (DAS28 Յ2.6); serious adverse events; and serious infections. RESULTS Of the 300 randomized patients (243 [83.2%] women; mean [SD] age, 57.1 [12.2] years; baseline DAS28-ESR, 5.1 [1.1]), 269 (89.7%) completed the study. At week 24, 101 of 146 patients (69%) in the non-TNF group and 76 (52%) in the second anti-TNF group achieved a good or moderate EULAR response (OR, 2.06; 95% CI, 1.27-3.37; P = .004, with imputation of missing data; absolute difference, 17.2%; 95% CI, 6.2% to 28.2%). The DAS28-ESR was lower in the non-TNF group than in the second anti-TNF group (mean difference adjusted for baseline differences, −0.43; 95% CI, −0.72 to −0.14; P = .004). At weeks 24 and 52, more patients in the non-TNF group vs the second anti-TNF group showed low disease activity (45% vs 28% at week 24; OR, 2.09; 95% CI, 1.27 to 3.43; P = .004 and 41% vs 23% at week 52; OR, 2.26; 95% CI, 1.33 to 3.86; P = .003). CONCLUSIONS AND RELEVANCE Among patients with rheumatoid arthritis previously treated with anti-TNF drugs but with inadequate primary response, a non-TNF biologic agent was more effective in achieving a good or moderate disease activity response at 24 weeks than was the second anti-TNF medication.