ABSTRACT
BACKGROUND: The purpose of this study was to evaluate the long-term safety and therapeutic effects of IFN-alpha in patients with severe persistent uncontrolled asthma on long-term oral glucocorticoid (GC) treatment. PATIENTS AND METHODS: The study included 16 patients (2 male, 14 female; age 39 years [range: 24 - 63]) with severe persistent asthma. Diagnosis and severity classification of asthma were established according to the guidelines of the "Deutsche Atemwegsliga". Eight patients stopped the therapy within 7 months due to side effects (n = 3), costs not covered by health insurance (n = 2), non-compliance (n = 2), and change of residence (n = 1). 8 patients (8 female, age 49 years [range: 35 - 68], duration of disease 16 years [range: 5 - 24]) were treated for at least 12 months with IFN-alpha (9 microg) 3 times/week. All patients were on oral glucocorticoids (GCs) for more than 5 years (average dose 17.5 [range: 5.0 - 64.0] mg/d). Clinical signs, lung function, need for reliever medication, number of emergency visits and hospitalisations and diary were assessed prior to and after 12 months of treatment. Data are given as percent of normal or median [range]. RESULTS: IFN-alpha improved lung function after 12 months: FEV1 64 vs. 75 %; FEV1/IVC 76 vs. 89 %; RV 153 % vs. 129 %; Rtot 193 vs. 111 % and morning PEF by 50 - 190 L/min. IFN-alpha also significantly reduced the use of reliever medication (10 [2 - 20] vs. 1 [0 - 3] puffs/d), nocturnal awakening (11 [4 - 30] vs. 1 [0 - 5]/month), emergency visits (7 [2 - 15] vs. 0 [0 - 5]/month) and hospitalisations (4 [1 - 8] vs. 0 [0 - 5]/year). In 5 patients the asthma attacks and nightly disturbances disappeared completely. The improvements were achieved despite a tapering of the oral GCs in all patients from 17.5 (5.0 - 64.0) to 2 (0 - 16) mg/d. In 5 patients GC treatment could be discontinued. The number of blood eosinophils decreased from 0.46 to 0.28 Gpt/L. Adverse events were transient and usually decreased within 3 to 4 weeks. Two patients developed an autoimmune thyreoiditis. CONCLUSION: In severe persistent, uncontrolled, and GC-dependent asthma, treatment with IFN-alpha leads to sustained clinical improvement and allows the reduction or discontinuation of oral GCs. Severe side effects may occur in isolated cases.