Methotrexate may have a small steroid sparing effect in adults with asthma who are dependent on oral corticosteroids. However, the overall reduction in daily steroid use is probably not large enough to reduce steroid-induced adverse effects. This small potential to reduce the impact of steroid side-effects is probably insufficient to offset the adverse effects of methotrexate.
Lack of benefit of methotrexate in severe, steroid-dependent asthma. A double-blind, placebo-controlled study.
To determine the effect of low-dose methotrexate in asthmatic patients on steroid use, asthma symptom scores, pulmonary function, airway reactivity, blood cellular components, and immunoglobulin E levels.
                A randomized, double-blind, parallel, placebo-controlled, 13-week clinical trial with follow-up of patients in an open trial of methotrexate at the conclusion of the double-blind study.
                An asthma care outpatient clinic.
                From February 1988 to March 1990, 19 patients with severe, steroid-dependent asthma were enrolled in the study. Two of these patients were excluded from analysis.
                Patients were administered methotrexate or placebo intramuscularly, to assure complete absorption, once weekly during the 13-week study.
                Patients on methotrexate and placebo both significantly decreased their steroid dose by 39.6% (95% CI, 25.1% to 54.1%, P = 0.001) and 40.2% (CI, 17.9% to 67.4%, P = 0.003), respectively. Pulmonary function did not differ significantly between the methotrexate and placebo groups. In addition, airway reactivity and symptom scores were unchanged on methotrexate or placebo. No significant toxicities were seen during the course of the 13-week blinded study, but one patient on methotrexate and prednisone in the follow-up period developed Pneumocystis carinii pneumonia and died. Despite continuing methotrexate for up to 1 year, and increasing methotrexate to 30 mg weekly, no significant benefit of methotrexate on asthma control could be shown.
                Our study does not support the use of methotrexate in the treatment of severe asthma.