The pathogenesis of rheumatoid arthritis (RA) is characterised by interactions between several types of immune cells, which are associated with the release of multiple inflammatory cytokines. Recently, numerous biologic treatments targeting classes of immune cells, cytokines or intra-cellular pathways of pro-inflammatory signals have been developed. Some of them are currently under research as potential therapeutic options for RA patients. This chapter reviews the available evidence regarding the safety and efficacy of new biologic agents targeting B cells, proinflammatory interleukins (IL), T helper 17 (Th17) pathway and intracellular enzymes. This chapter reviews the most relevant randomised controlled trials (RCTs) which have proven the efficacy of different biologic agents and small molecule inhibitors in controlling the inflammation associated with RA. The management of RA remains a dynamic and evolving field. The development of less expensive ‘biosimilar’ drugs, analogous to existing licensed biologic therapies, is an emerging area of research that deserves particular attention
