Efficacy, safety and tolerability of using abatacept for the treatment of rheumatoid arthritis

The objective is to provide an update on the clinical efficacy, safety and tolerability of the use of abatacept for treating rheumatoid arthritis. A systematic review (up to June 2011) followed by meta-analyses was performed. Randomized controlled clinical trials comparing abatacept at a dose of 10 mg/kg with a placebo, both with concomitant methotrexate, were used. Only high- or moderate-quality studies were included. The efficacy was evaluated based on changes in the ACR, DAS and HAQ; safety was assessed based on serious adverse events, serious infections, malignancies and deaths; tolerability was evaluated based on the withdrawals due to adverse events, serious adverse events and lack of efficacy. All these parameters were evaluated within one year of treatment. Nine studies met the inclusion criteria, comprising 4,219 patients. For all of the efficacy parameters, the abatacept group had better results than the placebo group, except in the case of HAQ improvement >0.3, which presented no statistically significant difference. None of the safety parameters presented a significant difference between the groups. The tolerability parameters were also similar between groups, with the exception of withdrawals due to lack of efficacy. For this criterion, the abatacept group presented favorably compared to the control group. Abatacept showed a higher efficacy compared to placebo without significant differences between the abatacept and control group in terms of safety