Objective: To evaluate safety and efficacy of longterm etanercept treatment in patients with disease modifying antirheumatic drug (DMARD) refractory rheumatoid arthritis (RA).
Methods: Safety results are reported for 714 patients who received etanercept in one of 7 initial trials or a longterm extension. Efficacy results are reported for 581 patients who enrolled in the extension.
Results: Of the 714 patients enrolled in the initial trials, 581 (81%) enrolled in the extension, and 388 (54%) patients are continuing to receive etanercept therapy. The longest individual treatment was 8.2 years, with 3139 total patient-years of etanercept exposure. Rates of serious adverse events (overall rate=14.8 events/100 patient-yrs), serious infections (overall rate=4.2 events/100 patient-yrs), cancer (overall rate=1.0 events/100 patient-yrs), and deaths (overall rate=0.7 events/100 patient-yrs) were stable each year, through 8 years of etanercept exposure. For 356 patients who completed 6 years of etanercept treatment, response rates were ACR20=73%, ACR50=52%, ACR70=27%, DAS28 CRP good response=52%, and DAS28 CRP remission=37% of patients. Similar responses occurred in 167 patients who completed Year 7. Doses of concomitant methotrexate or corticosteroids were reduced in many patients who maintained clinical responses.
Conclusion: The safety profile of etanercept was consistent over time, with rates of adverse events similar to those reported for patients with RA in general. Durable clinical responses were observed in some patients for 7 years or more. The benefit-to-risk ratio for longterm etanercept treatment remains highly favorable.