Azathioprine for Non-infectious Ocular Inflammation

Abstract

Purpose: : To evaluate the effectiveness of azathioprine as a sole immunosuppressive agent in patients with non-infectious ocular inflammatory diseases.

Methods: : All patients with a diagnosis of non-infectious ocular inflammatory diseases who initiated treatment with azathioprine_but no other non-corticosteroid immunosuppressive drug_were identified at five tertiary uveitis services. Medical records of participants were reviewed, and response to therapy, dose of prednisone, history of previous immunosuppressive drugs, and reasons for discontinuation of azathioprine therapy were recorded over time.

Results: : Among the 209 patients (376 eyes with ocular inflammation) initiating treatment with azathioprine, 11%, 18%, and 38% had anterior, intermediate and posterior or panuveitis respectively; 14% had scleritis; 16% had mucous membrane pemphigoid; and 3% had other inflammatory diseases. By Kaplan-Meier estimation, 39% (95%CI, 31-48%) of patients with active disease experienced an improvement of inflammation within ≤6 months to ‘inactive’ or ‘slightly active,’ sustained over ≥2 visits spanning ≥28 days; 24% (95%CI, 18-32%) maintained complete control of inflammation while tapering prednisone to 10 mg daily or less within 6 months of initiating azathioprine therapy. Over the median follow-up of 210 days (interquartile range, 63-608), 133 patients (64%) discontinued azathioprine: 23% due to side effects, 15% due to failure to control inflammation, 11% due to remission of disease, and 15% due to unspecified causes. The most common side effect leading to discontinuation was gastrointestinal upset, with an occurrence rate of 0.06/PY.

Conclusions: : Using these criteria for success, azathioprine was modestly effective for control of intraocular inflammation. However, results were substantially better using less stringent success criteria. Therapy was well-tolerated by the large majority of patients, and the observed side effects were typically reversible with dose adjustment or discontinuation of therapy.

Keywords: uveitis-clinical/animal model • clinical (human) or epidemiologic studies: outcomes/complications • drug toxicity/drug effects