Interleukin-6: Pathophysiology and Clinical Implications in Rheumatoid Arthritis

Looking Ahead: Tackling the Challenges

According to Dr Curtis and Dr Singh, “presently, even with early aggressive combination therapy, only about one-third of patients meet the criteria for clinical remission of RA.”6

Clearly, there is a continuing need for the development of new, effective, and affordable therapies for RA. However, multiple challenges exist on this path.

One of them is the need to clarify the mechanisms that govern the persistent overproduction of IL-6 in RA and those that make IL-6 blockade efficacious.8 Furthermore, a better understanding of the effects of IL-6 inhibition on the predisposition to opportunistic infections is needed.29

Another major challenge is identifying those patients with RA who are most likely to benefit from treatment with a specific biologic agent. Predictive biomarkers of response to treatment have not been adopted in RA,30 which makes the therapeutic decision-making process largely empiric: those patients who fail to respond adequately to initial treatment are switched between therapies with the aim of achieving a response. This approach results in inadequately controlled disease in approximately 40% of patients.6

Finally, there are concerns about the cost of treating RA with biologics. One study estimated that the mean annual direct cost of treating patients with biologic agents is 3-times greater than the cost of treatment that did not include biologics.31 However, researchers warn that only a small number of cost-benefit analyses to date have looked at the long-term cost-effectiveness of biologics.6

“Importantly, improving outcomes with early treatment strategies may reduce healthcare costs and morbidity (eg, need for joint replacement, premature disability) in the long term, thereby offsetting the relatively high direct treatment costs associated with biologics,” Dr Curtis and Dr Singh emphasized, adding that “although biologics are more costly in the short term than conventional DMARDs, cost will clearly be influenced by factors such as dosing intervals and routes of administration, which vary between agents.”6

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