OBJECTIVES: To evaluate the cost per ACR70 response rate of biologic disease-modifying antirheumatic drugs (bDMARDs) in the treatment of patients with active rheumatoid arthritis (RA) and inadequate response to traditional DMARDs (DMARD-IR) from the perspective of the Portuguese public health service. METHODS: A systematic literature review considering randomized, controlled, double-blind, multicentric clinical trials that evaluated the efficacy of bDMARDs’ - abatacept, adalimumab, etanercept, golimumab, infliximab and tocilizumab – in combination with DMARDs in the treatment of patients with active RA and DMARD-IR, was performed, and 22 clinical trials were identified. ACR70 response rates in each trial were adjusted for a placebo reference rate, which incorporated the placebo response rates observed in all the trials. Odds ratio between the placebo group and the placebo reference group was thus assumed to reflect the baseline differences between each trial results and a global reference population. Meta-analyses were then performed to obtain the adjusted ACR70 response rate for each bDMARD. The analysis considered drug and administration costs, obtained from Portuguese official sources, and a 6-month time horizon. RESULTS: The highest adjusted ACR70 response rate was obtained with tocilizumab (31,3%) followed by adalimumab (25%), golimumab (20,2%), infliximab (19,6%), etanercept (15,5%) and abatacept (11,7%), which is in line with earlier published evidence. Treatment costs were lower with infliximab (4.577€) followed by tocilizumab (5.366€), etanercept (5.695€), golimumab (5.921€), adalimumab (6104€) and abatacept (7.764€). The lowest mean treatment cost to achieve an ACR70 response was obtained with tocilizumab (17.143€) followed by infliximab (23.354€), adalimumab (24.414€), golimumab (29.311€), etanercept (36.743€) and abatacept (66.356€). CONCLUSIONS: Due to the higher predicted ACR70 response rate, using tocilizumab for the treatment of adult RA DMARD-IR patients provides the lowest cost per 70% or higher improvement in disease activity among bDMARDs.