Treatment of ocular symptoms of Behçet's disease with interferon alpha 2a: a pilot study

Abstract

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.

Figure 1

Patient no 4 (A) Reconstruction of fundus photographs before treatment. Optic disc oedema, circular peripapillar flame-shaped haemorrhages, no central reflexes. Greyish appearance of the macula because of oedema is seen at the posterior pole. In all four quadrants in the periphery there are white infiltrates of the inner retina with blurred rims partially associated with intraretinal haemorrhages. There is diffuse scattered vasculitis most pronounced along the lower temporal branch vein with lower temporal branch stasis and marked intraretinal haemorrhages. (B) 14 days after treatment with 6×10⁶ IU IFNα_2a/day. Retinal infiltrates have completely resolved, optic disc and macular oedema regressed. Haemorrhages have partially resolved. Vascular sheathing persisted especially at the lower temporal branch vein, but there is clearly visible reperfusion of the lower branch vein. (C) 28 days after treatment with 6×10⁶ IU IFNα_2a/day. The optic disc is still minimally blurred. Macular oedema has resolved but central reflexes are irregular. Haemorrhages have markedly resolved. Vascular sheathing has disappeared except at a small lower temporal peripheral venule which still shows persistent occlusion and non-perfusion in the fluorescein angiogram.

Figure 2

Patient no 5 (A) Optic disc and posterior pole of the left eye before treatment with 3×10⁶ IU IFNα_2a/day. Optic disc shows hyperaemia with flame-shaped haemorrhages and marked oedema inferiorly. There is vasculitis of several veins of the two lower retinal quadrants. The lower temporal veins are tortuous and less oxygenated. (B) 28 days after treatment peripapillar haemorrhages and oedema have resolved. Collateral vessels have formed to the occluded lower branch vein, which now shows almost normal perfusion.

Figure 3

Patient no 5 (A) Fluorescein angiography left eye mid transit (228 seconds) before treatment. There is irregular choroidal filling, delayed filling of the lower temporal branch vein, occlusive vasculitis leading to profound structural changes of the retinal vessels. (B) 8 weeks after initiation of treatment. There is relatively regular filling of the choroid and almost no delay of filling of the lower temporal vein partially due to the collateral vessels.