Translating co-stimulation blockade into clinical practice.

Currently available information from clinical trials and open-label extensions suggest that abatacept is a good alternative to other biologicals in rheumatoid arthritis. Although at first glance the efficacy of all biologicals appears to be the same, in routine practice one might expect there to be differences in effectiveness, safety profiles and specific patient-centered outcomes. These patient-centered outcomes, as well as safety, deserve further attention in follow-up registries, but also in prospective studies, if we are to optimize patient care. After failing a first tumor necrosis factor blocker, patients have several treatment options - starting a second tumor necrosis factor blocker, or rituximab or abatacept - but no formal randomized studies are available to indicate what is the optimal strategy. Potential differences between treatments with biologicals with different modes of action in very early disease also require more study. It is difficult to determine how co-stimulation blockade will influence Crohn's disease or psoriatic arthritis as well as other diseases characterized by a specific role of the adaptive immune system, such as systemic lupus erythematosus and multiple sclerosis. It is clear, however, that every additional targeted therapy creates new opportunities for treatment in many different patient populations.