PsA Patients Sticking to Etanercept Therapy

Etanercept is a viable long-term treatment strategy for patients with psoriatic arthritis, and is both safe and effective when used in daily clinical practice, according to a new prospective long-term study. The PROVE study was a prospective, multi-center, open-label, observational study in patients with active psoriatic arthritis who had previously failed disease-modifying anti-rheumatic drugs. The study included 303 patients (264 polyarticular-type, 39 oligoarticular-type) who were treated with etanercept and monitored for more than 66 months. Previous longitudinal adherence studies have been of shorter duration and involved patients taking a range of tumor necrosis factor alpha (TNFα) inhibitors.  The researchers considered adherence to be high, with mean study duration of 4 years and more than half of patients remaining in the study for at least 5.5 years. The mean adherence to treatment time was 4.5 years. The main reasons for withdrawal, as in other studies, were non-response (36%) and adverse events. Treatment-related adverse events were reported in more than half (58.8%) of patients, and 17.6% of patients reported serious adverse events related to treatment. Men were more likely to adhere to treatment (5 years) than women (3.9 years), which also echoes the results from other studies. They noted that the greatest improvement in clinical symptoms occurred within the first 6 months, during which time very few patients withdrew due to non-response.  After 6 months, inefficacy became the main reason for withdrawal. Patients with a longer disease duration (4 or more years) stayed in the study longer than those with a shorter disease duration (less than 4 years), for an unknown reason. After 6 months, 49% of patients with active synovitis at the start of the study had zero joints with synovitis. At 66 months, this increased to 77.6%. Polyarticular-type patients showed 65% improvement in mean total Health Assessment Questionnaire score at 6 months, which was maintained at 66 months. Concomitant methotrexate made no significant difference in adherence, even among non-responders. “These results differ from the data obtained from other studies, which observed that patients receiving concomitant methotrexate were more likely to stick with TNF-α inhibitor treatment,” the researchers stated. They pointed out that over the 5½ years, etanercept was generally well-tolerated and the rate of adverse events and infections was comparable to previous psoriatic arthritis studies and published safety data in psoriatic arthritis patients.    

References:

de Vlam K, Boone C, The Prove Study Group A.

"Treatment adherence, efficacy, and safety of etanercept in patients with active psoriatic arthritis and peripheral involvement in Belgium for 66 months (PROVE study),"

Clinical and Experimental Rheumatology. 2015 Sep-Oct;33(5):624-31. Epub 2015 Jul 23.