Is the patient's baseline inhaled steroid dose a factor for choosing the budesonide/formoterol maintenance and reliever therapy regimen?

OBJECTIVE: Baseline inhaled corticosteroid (ICS) dose may be a factor for prescribers to consider when they select a budesonide/formoterol maintenance and reliever therapy regimen for symptomatic asthmatics.

METHODS: A 6-month randomized study compared two maintenance doses of budesonide/formoterol 160/4.5 µg, 1 × 2 and 2 × 2, plus as needed, in 8424 asthma patients with symptoms when treated with ICS ± an inhaled long-acting β(2)-agonist (LABA). In the total study population, 1339 (17%) were high-dose ICS (HD) users (≥ 1600 µg/day budesonide). This HD stratum was compared with the rest of the study population, divided into low-dose (LD; 400 µg/day) and medium-dose strata (MD; 401-1599 µg/day) with regard to severe asthma exacerbations and mean changes in five-item Asthma Control Questionnaire (ACQ(5)) scores from baseline.

RESULTS: In all three strata there were fewer exacerbations in the 2 × 2 treatment groups (yearly rates 0.268, 0.172 and 0.094) than in the 1 × 2 treatment groups (yearly rates 0.232, 0.138 and 0.764). In no stratum was the difference between the treatment groups statistically significant. There was no statistically significant difference in time to the first severe exacerbation between the treatments 2 × 2 and 1 × 2 in the HD group (hazard ratio 0.944, p = 0.75). The adjusted mean changes in ACQ(5) scores in the HD, MD and LD strata were -0.89, -0.61 and -0.65, respectively, with 1 × 2 treatment and -0.90, -0.74 and -0.76, respectively, with 2 × 2 treatment. In the MD and LD strata, the difference between doses was significant in favour of 2 × 2 (MD p < 0.0001; LD p = 0.004), but not in the HD stratum (p = 0.870). No difference in serious adverse events was seen.

CONCLUSION: Compared with the LD and MD strata, the HD stratum patients had more exacerbations and a shorter time to first exacerbation. However, there were no differences in response between the 1 × 2 and 2 × 2 groups in any of the strata. This indicates that patients using budesonide/formoterol maintenance and reliever therapy, irrespective of baseline ICS dose, can be switched to 1 × 2 with its lower steroid load. ACQ(5) scores improved more in the HD stratum than in the MD and LD strata indicating, among other things, that HD patients were not overtreated at baseline.