Objective: The purpose of this study was to evaluate the feasibility of switching to once-daily (qd) administration of flunisolide in patients with asthma that was controlled by twice-daily (bid) dosing of this inhaled steroid.
Methods: Three hundred sixty-six adults and children with bronchial asthma that was controlled with inhaled steroids were recruited for this prospective, double-blind, parallel-group study. After a 4-week, stable baseline period of flunisolide administration, 2 inhalations (500 microg) twice daily, each patient was randomized into one of four 12-week flunisolide treatment groups: group 1, 2 inhalations (500 microg) bid; group 2, 4 inhalations (1000 microg) qd in the morning; group 3, 4 inhalations (1000 microg) qd in the evening; or group 4, 2 inhalations (500 microg) qd in the morning. Outcome measures included morning and evening asthma symptoms (scale of 0 to 3), daytime and nighttime albuterol use, morning and evening peak expiratory flow rate (PEFR), FEV1, and methacholine PC20. In addition, a subset of patients in each group had 24-hour urinary cortisol levels measured before and after randomization.
Results: Outcome measures in the four groups were not significantly different at baseline before randomization. The three groups that received maintenance therapy with flunisolide, 1000 microg daily, did not show significant changes from baseline values and remained comparable in all outcome areas. Asthma control in the group randomized to flunisolide 500 microg qd, however, deteriorated significantly: morning symptoms increased by 0.21 units (48%), evening symptoms increased by 0.15 units (31%), daytime albuterol use increased by 0.42 inhalations per day (37%), nighttime albuterol use increased by 0.48 inhalations per night (91%), morning PEFR decreased by 17.1 L/min (4%), and evening PEFR decreased by 12.6 L/min (3%). There were no significant changes in PC20 or 24-hour urinary cortisol levels in any group.
Conclusions: For patients with asthma that was stabilized by 2 inhalations of flunisolide (500 microg) bid, switching to 4 inhalations (1000 microg) qd in either the morning or evening is effective in maintaining asthma control. Reducing the dose to 2 inhalations (500 microg) qd in the morning, however, leads to a deterioration in asthma control.