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.
Comparison of methotrexate 30 mg per week with placebo in chronic steroid-dependent asthma: a 12-week double-blind, cross-over study.
Methotrexate has been shown to have a steroid-sparing effect in chronic steroid-dependent asthmatics at a dose of 15 mg week-1. The aim of this study was to investigate the steroid-sparing activity and adverse events profile of methotrexate 30 mg week-1 in severe steroid-dependent asthma. Eighteen patients who had required 10-50 mg week-1 prednisolone for at least 6 months were asked to participate in a randomized, double-blind, placebo-controlled cross-over study lasting 24 weeks. Daily diary cards of symptoms, peak expiratory flow rate and medication requirements were kept and the patients attended for a chest X-ray, spirometry, lung volumes and gas transfer at commencement and after each 12-week treatment period. Every 3 weeks, adverse events were noted and blood taken for full blood count, urea and electrolytes and liver function tests. Twelve patients completed the trial. Withdrawals were due to non-compliance in two patients, pneumonia in two patients, depression in one patient (on placebo) and severe nausea in one patient. Adverse events were common, probably as a consequence of the higher dosage. Prednisolone requirements were not significantly reduced on methotrexate. Lung function improved on methotrexate with a significant rise in maximal mid-expiratory flow rate and a trend towards improvement in FEV1.