Aim: To study long term effects of interferon alpha 2a (IFN alpha 2a) on panuveitis in seven patients with Behçet's disease in a prospective, open clinical trial.
Methods: Seven patients were treated with IFN alpha 2a for a mean of 23.6 months (14-37 months). They received an initial dose of IFN alpha 2a of 6 x 10(6) IU/day, followed by 3 x 10(6) IU/day after 1 month and 3 x 10(6) IU every other day after 3 months. Two patients received low dose prednisolone (between 0.2 and 0.4 mg/kg/body weight) additionally at the beginning of the therapy. Complete cessation of IFN alpha 2a was possible in three patients (observation period 22, 6, and 4 months).
Results: Marked improvement occurred in six patients who had ocular manifestations of Behçet's disease for the first time or with minor damage during their course of chronic relapsing panuveitis. In one patient with advanced ocular Behçet's disease, new relapses were prevented. Retinal infiltrates resolved within 2 weeks; vasculitis, macular oedema, infiltration of the anterior chamber and vitreous resolved within 4 weeks. Mean posterior uveitis score before treatment (nine affected eyes) was 6.6, 4 weeks after IFN it was reduced to 0.4. The mean observation period is 27.6 months, ranging from 14 to 42 months.
Conclusion: Treatment of ocular symptoms of Behçet's disease with IFN alpha 2a alone or in combination with low dose steroids led to complete remission of ocular vasculitis in all patients treated in this open, uncontrolled trial. Treatment with IFN alpha 2a may prevent permanent retinal or optic nerve damage due to vascular occlusion. No severe side effects occurred. Controlled randomised studies are warranted in order to prove the efficacy of IFN alpha 2a in ocular Behçet's disease and to compare it with other, established treatments such as azathioprine or cyclosporin A.