Budesonide/formoterol superior to terbutaline in mild asthma
The combination of the inhaled corticosteroid (ICS) budesonide and the LABA* formoterol administered on an as-needed (PRN) basis was superior to the SABA** terbutaline for symptom control and exacerbation risk reduction in patients with mild asthma, according to SYGMA 1*** results presented at ATS 2018.
SYGMA 1 comprised 3,849 patients with physician-assessed mild asthma who were randomized 1:1:1 to receive twice-daily placebo either with budesonide/formoterol 200/6 μg PRN or terbutaline 0.5 mg PRN, or a budesonide maintenance regimen comprising twice-daily budesonide 200 μg plus terbutaline 0.5 mg PRN, for 52 weeks. [ATS 2018, abstract A7655]
In terms of symptom control (electronically-recorded well-controlled asthma weeks), budesonide/formoterol was superior to terbutaline (odds ratio [OR], 1.14, 95 percent confidence interval [CI], 1.00–1.30; p=0.046) but inferior to budesonide maintenance (OR, 0.64, 95 percent CI, 0.57–0.73).
Compared with terbutaline, budesonide/formoterol reduced the rate of moderate-to-severe and severe exacerbations (risk ratio [RR], 0.40, 95 percent CI, 0.32–0.49; p<0.001 and RR, 0.36, 95 percent CI, 0.27–0.49; p<0.001, respectively), while no significant difference in these outcomes was observed between patients on budesonide/formoterol and budesonide maintenance (RR, 0.95; p=0.66 and RR, 0.83; p=0.28, respectively).
Despite the inferiority of budesonide/formoterol to budesonide maintenance in terms of symptom control, both regimens were comparable in preventing exacerbation, the researchers pointed out.
Budesonide/formoterol also improved the time to first severe exacerbation vs terbutaline (hazard ratio [HR], 0.44, 95 percent CI, 0.33–0.58; p<0.001) but was not significantly different from budesonide maintenance (HR, 0.90, 95 percent CI, 0.65–1.24; p=0.52).
Differences in change from baseline favoured budesonide/formoterol over terbutaline for ACQ-5# (mean difference, -0.15, 95 percent CI, -0.20 to -0.11) and prebronchodilator FEV1## (mean difference, 53.8 mL, 95 percent CI, 29.1–78.5).
Adverse event rates were similar between all treatment groups (43, 38, and 40 percent in the terbutaline, budesonide/formoterol, and budesonide maintenance groups, respectively).
SYGMA 2 also demonstrated noninferiority of budesonide/formoterol 200/6 μg PRN to budesonide maintenance in terms of annualized severe asthma exacerbation rate (rate ratio, 0.97, 95 percent CI, NA–1.16) [ATS 2018, abstract A7654]
Both budesonide/formoterol and budesonide maintenance groups also had similar rates of severe exacerbations requiring emergency department visits (1.2 percent vs 1.7 percent) or hospitalizations (0.8 percent for both), as well as time to first severe asthma exacerbation (HR, 0.96, 95 percent CI, 0.78–1.17; p=0.66).
Addressing ICS underutilization
Despite guideline recommendations favouring ICS for asthma maintenance therapy, there is poor adherence to ICS as patients prefer SABAs for symptom relief despite its inability to protect against exacerbations or address airway inflammation. [J Asthma Allergy 2010;3:169-176; Global Strategy for Asthma Management and Prevention 2018, http://ginasthma.org/, accessed 24 May 2018; Eur Respir J 2017;50:1701103; Ann Allergy Asthma Immunol 2012;109:403-407]
“[Our results show that] a combination of fast-acting β2-agonist and ICS taken only ‘as needed’ for rapid symptom relief may address underuse of ICS and reduce exacerbations for patients with mild asthma,” said the researchers.