According to JAMA, one third of patients with juvenile idiopathic arthritis (JIA) starting receiving etanercept treatment demonstrated excellent responses. Etanercept, approved 10 years ago by the U.S. FDA and European Agency for the treatment of JIA, is linked to younger age at the onset of JIA, low measures of disability at study entry and fewer disease-modifying antirheumatic drug use before starting etanercept therapy. The study will be presented at the American College of Rheumatology/Association of Rheumatology Health Professionals Annual Scientific Meeting.
Background information in the article says:
“Since the development of biological agents, the pharmacological treatment approach of JIA is changing rapidly, and synthetic disease-modifying antirheumatic agents (DMARDs) are used earlier in the disease course, which seem to provide better long-term outcomes. As a result of these treatment successes, a treatment goal of reaching inactive disease now seems realistic. However, inactive disease is still not achieved in a substantial proportion of cases, and current approaches need to be optimized even more. The ability to identify patients who are more likely to respond to etanercept treatment would be an important step toward tailored patient-specific treatment and subsequently could improve current treatment approaches.”
Lead author Marieke H. Otten, M.D., M.Sc., of the Erasmus MC Sophia Children’s Hospital in Rotterdam, The Netherlands and her team decided to assess JIA disease activity after initiating etanercept treatment and to establish characteristics linked to responses in treatment. They utilized data from the Arthritis and Biologicals in Children Register, an ongoing prospective observational study since 1999 that contains all Dutch JIA patients who received biologic agents. The study included all biologically naïve, i.e. patients who had not previously received a biological agent, who started etanercept therapy before October 2009 and follow-up data to January 2011. The total number of 262 patients included 185 (71%) female patients and 46 (18%) with systemic-onset of the disease with an average age of 12.4 years at the start of etanercept treatment.
Researchers assessed the participants’ responses to the treatment 15 months after the start of treatment with etanercept. They defined ‘excellent response’ as inactive disease or discontinuation earlier due to disease remission, and ‘intermediate response’ as more than 50% improvement from baseline, but no inactive disease, whilst ‘poor response’ was defined as less than 50% improvement from baseline or discontinuation earlier due to ineffectiveness or intolerance.
After 15 months, researchers established that 85 (32%) of the total of 262 patients responded ‘excellent’, whilst 85 patients (32 percent) demonstrated ‘poor responders’ and the other 92 patients showed ‘intermediate response’. The findings revealed that those who demonstrated ‘excellent response’ were linked to lower scores on disability measures at study entry, a younger age at disease onset and a low number of DMARDs, including methotrexate before being introduced to etanercept compared with those who achieved intermediate or poor responses. They also established that poor response was linked to systemic JIA and females in comparison to those with intermediate or excellent response.
199 patients developed 1 or more adverse events, such as infectious, non-infectious or serious AEs. 37 of these patients were in the ‘excellent response’ group, with 36 in the ‘intermediate group’ and 46 in the ‘poor response group’. 53 patients reported at least 1 infectious adverse event or an infectious serious adverse event.
A total of 61% participants discontinued etanercept therapy within the first 15 months of treatment, of which 4 had an excellent response and 57 a poor response. All participants with intermediate response finished their treatment. The authors comment:
“In a secondary analysis of 262 patients with a median follow-up of 35.6 months after initiation of etanercept, a range of 37% to 49% of patients reached inactive disease. [Average] drug survival [i.e., average duration from start until first discontinuation due to ineffectiveness or adverse events] was 49.2 months for patients with an excellent response after 15 months, 47.5 months for patients with an intermediate response, and 17.4 months for patients with a poor response.”
During the overall etanercept treatment the researchers noted 31 serious, 99 infectious and 179 non-infectious adverse events.
Written by Petra Rattue