BACKGROUND:
Tumor necrosis factor (TNF)-alpha is produced by macrophages and other cells, and is believed to participate in granulomatous inflammation. Targeted antagonism of TNF-alpha has been proposed as a novel treatment strategy for sarcoidosis. Etanercept is a dimeric fusion protein that binds specifically to TNF-alpha, rendering it biologically inactive.
OBJECTIVE:
To assess whether etanercept has potential efficacy in the treatment of progressive pulmonary sarcoidosis.
DESIGN:
Prospective, open-label, phase-2 treatment trial.
SETTING:
Mayo Clinic, Rochester, MN.
PATIENTS:
Stage II or III progressive pulmonary sarcoidosis.
INTERVENTION:
Etanercept, 25 mg subcutaneously twice weekly.
MEASUREMENTS:
Pulmonary function, chest radiographs, dyspnea, and TNF-alpha levels in serum and BAL fluid.
RESULTS:
The study was terminated after the enrollment of 17 patients due to an early-stop clause of the pretrial study design related to excessive treatment failures. Neither absolute levels of TNF-alpha nor TNF-alpha activity in the serum, BAL fluid, or alveolar macrophages were able to predict which patients would respond to etanercept.
CONCLUSIONS:
In patients with progressive stage II or III pulmonary sarcoidosis, etanercept was frequently associated with early or late treatment failure. These data would not support the design of a large multicenter randomized trial comparing etanercept with conventional corticosteroid therapy.