Introduction: In some steroid refractory patients with active ulcerative colitis (UC), treatment with immunosuppressive agents, such as cyclosporin, azathioprine or 6-mercaptopurin is effective. However, there are patients who fail to respond to these treatment options or who cannot tolerate them. Application of natural interferon-beta (nIFN-beta) may offer an alternative. Following our positive results with nIFN-beta in a previously published open-labeled study, the present study was designed as an extension with the hypothesis that administration of higher dosage of nIFN-beta (1.0 vs. 0.5 MIU) could result in fewer relapse events.
Patients and methods: 46 steroid refractory patients with active UC and a mean clinical activity index (CAI) of 13.2 +/- 3.7 (range 9-23) were treated with nIFN-beta in addition to existing basic medication (5-ASA/SASP plus corticosteroids). During an induction period of eight weeks, 18 patients (group A) received 0.5 MIU nIFN-beta daily and 28 patients (group B), 1.0 MIU nIFN-beta daily intravenously as a bolus injection. Patients who achieved complete remission (decrease of CAI to < or = 4) during the induction period received maintenance therapy with nIFN-beta at the same dose level three times a week and corticosteroids were withdrawn. Remissions and maintenance of remissions were evaluated.
Results: In both groups, a comparable number of complete remissions occurred during the induction period: in 16 / 18 patients (89 %) in group A and in 24 / 28 patients (86 %) in group B. Duration of maintenance treatment was 60.0 +/- 90.0 weeks in group A and 52.7 +/- 9.6 weeks in group B. Under this treatment, relapses (increase of CAI to > or = 6) occurred in 5 / 16 patients (31 %) vs. 1 / 24 patients (4 %) (p < or = 0.05). Hence, regarding maintaining remissions, the 1.0 MIU group outscored the 0.5 MIU group. Apart from known flu-like side effects, the therapy was well tolerated by all patients in both groups.
Conclusion: nIFN-beta may be a safe and effective alternative to induce and maintain remissions in patients with steroid refractory active UC. To validate the presented results, its effect has to be investigated in a randomized, placebo-controlled dose-finding trial.