Study Compares Efficacy of Inhaled Corticosteroids with Formoterol or SABA versus SABA Alone for Asthma Reliever Therapy

Asthma is a global disease characterized by airway inflammation and airflow obstruction. Medications like short-acting β agonists [SABA] and inhaled corticosteroids (ICS) are prescribed to relieve the symptoms either alone or in combination. Research recommends inhaled corticosteroids along with formoterol as the preferred reliever over SABA alone while certain organizations recommend ICS-SABA as the reliever inhaler. As there is ambiguity in the optimal asthma reliever researchers conducted a systematic review of various inhaled relievers to compare short-acting β agonists (SABA) alone with SABA combined with inhaled corticosteroids (ICS) and with the fast-onset, long-acting β agonist formoterol combined with ICS for asthma.

Using data from search engines like the MEDLINE, Embase, and CENTRAL databases data was extracted without language restrictions. Pairs of reviewers independently selected randomized clinical trials evaluating (1) SABA alone, (2) ICS with formoterol, and (3) ICS with SABA (combined or separate inhalers). Data extraction and bias assessment were done by two reviewers. Outcomes were synthesized using the Random-effects meta-analyses. The outcomes measured were Asthma symptom control, asthma-related quality of life, risk of severe exacerbations, and risk of serious adverse events by using various questionnaires.

Findings:

• About 27 randomized clinical trials were included.
• It was found that when compared with SABA alone, both ICS-containing relievers were associated with fewer severe exacerbations with high certainty.
• Asthma control was also improved with, both ICS-containing relievers when compared with SABA alone with high certainty.
• There were very few severe exacerbations of asthma when an indirect comparison with ICS-SABA, and ICS-formoterol was done with moderate certainty.
• Compared with SABA alone, ICS-formoterol was not associated with an increased risk of serious adverse events (high certainty), and ICS-SABA was not associated with an increased risk of serious adverse events (moderate certainty).

Thus, the study concluded that inhaled corticosteroids combined with formoterol and inhaled corticosteroids combined with short-acting β agonists were each associated with reduced asthma exacerbations and improved asthma control compared with short-acting β agonists alone in asthmatics.

Further reading: Rayner DG, Ferri DM, Guyatt GH, et al. Inhaled Reliever Therapies for Asthma: A Systematic Review and Meta-Analysis. JAMA. Published online October 28, 2024. doi:10.1001/jama.2024.22700.