Age Does Not Influence Efficacy of Tiotropium Bromide in Adults With Asthma

In patients with asthma, age does not appear to influence the efficacy of once-daily tiotropium bromide when used as an add-on to inhaled corticosteroids (ICS) and ICS/long-acting beta-agonist (LABA) therapy, according to study results published in the Journal of Allergy and Clinical Immunology: In Practice.

The study was a post hoc analysis of 4 randomized, double-blind, phase 3 studies in adult patients with asthma. In 2 studies (PrimoTinA-asthma: ClinicalTrials.gov Identifier: NCT00776984 and ClinicalTrials.gov Identifier: NCT00772538), researchers compared once-daily 5 μg tiotropium (n=456) with placebo (n=456), whereas the other 2 studies (MezzoTinA-asthma: ClinicalTrials.gov Identifier: NCT01172808 and ClinicalTrials.gov Identifier: NCT01172821) compared once-daily 2.5 μg (n=519) or 5 μg tiotropium (n=517) with either twice-daily 50 μg salmeterol (n=541) or placebo (n=523).

The post hoc analyses examined several end points of efficacy at week 24, including trough and peak forced expiratory volume in 1 second (FEV₁), trough forced vital capacity, Asthma Control Questionnaire (ACQ) total score, and proportion of treatment responders. Analyses were performed with age as a continuous covariate as well as with age in defined categories (<40 years vs 40-60 years vs >60 years).

In the PrimoTinA-asthma and MezzoTinA-asthma trials, the mean ages of patients were 53.0 years and 43.1 years, respectively. Concerning trough FEV₁, efficacy was in favor of tiotropium in the continuum analyses. This efficacy end point was not influenced by age of participants. Additionally, age did not influence the effect of add-on 5 μg tiotropium to ICS or ICS/LABA therapy on mean ACQ in patients with moderate or severe asthma.

However, the investigators observed a slight influence of age on the ACQ responder analyses with continuous age in patients with moderate and severe asthma. A trend toward decreasing efficacy with increasing age was observed. Age did not have an effect on the overall frequencies of adverse events with tiotropium. Although the rates of asthma serious adverse events were slightly higher in the placebo groups, these rates were balanced across treatments.

Limitations of the analyses were the inclusion of patient subgroups with small sample sizes (particularly in the <40 years age category) as well as the lack of formal power for the comparison analyses.

The study findings demonstrated a lack of influence of age on tiotropium efficacy are particularly relevant to asthma care, considering “there is an increase in the aging population worldwide as well as increased prevalence of asthma in older individuals,” the researchers wrote.

Disclosure: This clinical trial was supported by Boehringer Ingelheim. Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.

Reference

Doherty DE, Bleecker ER, Moroni-Zentgraf P, Zaremba-Pechmann L, Kerstjens HAM. Tiotropium respimat efficacy and safety in asthma: relationship to age [published online April 19, 2020]. J Allergy Clin Immunol Pract. doi:10.1016/j.jaip.2020.04.013