Principles: Current asthma management employing inhaled corticosteroids (ICS) and longacting b2-agonists (LABA) aims to rapidly achieve and then maintain overall asthma control including symptoms with minimal medication. This study compared self-guided adjustable maintenance dosing with budesonide/formoterol in a single inhaler with fixed dosing.
Methods: In an open-label, parallel-group, multicentre study, 127 asthmatic patients, well controlled on ICS and LABA, were treated with budesonide/formoterol (Symbicort) Turbuhaler) 200/6 mg (equivalent to 160/4.5 mg delivered dose) 2 inhalations bid for 4 weeks, and were then randomised to budesonide/formoterol adjustable dosing (n = 69) (guided self-adjustment of dose: 1 inhalation bid or 2 inhalations at night with interim step ups to 2 inhalations bid and if not sufficient up to 4 inhalations bid for 14 days) or fixed dosing (2 inhalations bid) (n = 58) for 12 weeks.
Results: Patients used adjustable dosing effectively; >50% used a decreased maintenance dose on >50% of the days. Seventy-two percent (50/69) from the adjustable-dosing group reduced their maintenance dose within the first 2 treatment weeks. Thirteen adjustable-dose patients (18.8%) never reduced their dose and 4 (5.8%) stepped up their dose. Symptom severity (NHLBI severity grade) decreased in both groups; however, the decrease was only statistically significant (p = 0.004) in the adjustable-dosing group. Treatment failures occurred in 17% and 24% of patients (adjustable and fixed dosing, respectively p = 0.35). Nocturnal awakenings (0.057 vs. 0.067/night, p = 0.006) and rescue medication use (0.15 vs. 0.23 inhalations/day, p <0.0001) were significantly less frequent with adjustable dosing, and the average daily medication dose was significantly reduced (3.0 vs. 3.9, p <0.0001) compared with fixed dosing. Lung function measurements (FEV1 and PEF) were not significantly different between groups during the study. There were no asthma-related hospital admissions.
Conclusion: Asthma patients on adjustable maintenance dosing with budesonide/ formoterol maintained control of symptoms using significantly less medication overall than fixed dosing. Thus, adjustable maintenance dosing achieved guideline goals of effective asthma control at an appropriately low maintenance dose. However, larger studies on adjustable maintenance dosing are needed.