Background
Effective amelioration of symptoms and induction of remission are goals in treatment of rheumatoid arthritis (RA).
Objectives
Data from a Phase II study for RA treatment with abatacept, a selective co-stimulation modulator, showing induction of remission (DAS-28 score < 2.6) are presented.
Methods
Patients on background methotrexate (MTX) who met ACR criteria for active RA with ≥ 10 swollen joints (66 joint count) and ≥ 12 tender joints (68 joint count) were randomly assigned to receive 10 mg/kg abatacept (n = 115) or placebo (n = 119) treatment for 1 year. DAS-28 scores and serum cytokine levels were assessed at days 1, 90, 180 and 360.
Results
Abatacept-treated patients showed a progressive increase in remission rates up to 1 year (analysis not prespecified) compared with placebo (P < 0.001; Fig. 1). Abatacept treatment also decreased serum levels of proinflammatory cytokines. In particular, levels of serum IL-6, a multifunctional cytokine that contributes both to acute phase response and to pathological B cell activation, were reduced by 67% at 180 days and by 73% at 360 days (P < 0.05). Placebo-treated patients showed no reduction. Abatacept was generally safe and well tolerated.
Figure 1. Abatacept increases the remission rate in RA patients refractory to MTX treatment.
Means and 95% confidence intervals are shown.
Conclusions
In patients with active RA who were receiving MTX, abatacept treatment significantly improved RA symptoms and produced a progressive increase in remission rates for over one-third of the treatment group, which was sustained at 1 year. In addition, abatacept decreased serum IL-6 levels. The results of this phase II study suggest that abatacept may have potential as therapy for patients with active RA despite MTX treatment.
Acknowledgement
Study supported by Bristol-Myers Squibb.



