Adding a long-acting β-agonist (LABA) did not improve time to asthma exacerbation compared with adding tiotropium among black adults with asthma treated with inhaled corticosteroids, according to a multisite study that enrolled black adults with moderate to severe asthma. Patients received ICS plus either once-daily tiotropium (n=532) or twice-daily LABAs (n=538) and were followed-up for up to 18 months. Researchers found:

• The was no difference between LABA + ICS vs tiotropium + ICS in time to first exacerbation (RR=0.90).

• There was no difference in change in spirometry (FEV1) at 12 months, and at 18 months.

• There were no differences in Asthma Control Questionnaire (ACQ) scored at 18 months.

• Arg16Gly ADRB2 alleles were not associated with differences in the effects of tiotropium + ICS vs LABA + ICS. (HR 0.84 for time to first exacerbation).

Citation: Wechsler ME, Yawn BP, Fuhlbrigge AL, et al. Anticholinergic vs long-acting β-agonist in combination with inhaled corticosteroids in black adults with asthma: The BELT randomized clinical trial. JAMA. 2015;314(16):1720-1730. doi: 10.1001/jama.2015.13277.

Commentary: LABAs are effective bronchodilators, but there has been a question as to whether LABAs have less effect and are less safe in certain populations, particularly African Americans. This uncertainty raises the question of whether a long-acting anticholinergic such as tiotropium might be more effective and safer in combination with an ICS than a LABA. This is particularly relevant now that tiotropium, in the form of Spiriva Respimat, is FDA approved for the long-term, once-daily treatment of asthma in patients aged 12 years and older. This study shows that both LABAs and tiotropium are beneficial in the treatment of asthma in combination with an ICS, and both seem equally effective and safe. —Neil Skolnik, MD