Researchers Test LAMA Monotherapy in Asthma Patients

While long-acting muscarinic antagonists (LAMA) are indicated only as an add-on therapy for asthmatic patients, many clinicians have concerns regarding monotherapy use of the treatment.

A team, led by Esme J. Baan, Department of Medical Informatics, Erasmus University Medical Center, presented new data during the European Respiratory Society Congress 2020 (ERS 2020) Virtual Conference, examining the prevalence of LAMA monotherapy and its potential link to severe asthma exacerbations in patients with asthma.

In the cohort study, the investigators used data from the IPCI primary care database involving 66,508 asthma patients between 6-50 years who used LAMA during the follow-up period between 2007-2017. Each respiratory prescription was retrieved from the electronic medical records based on ATC code.

The research team categorized asthma treatment periods as LAMA mono, double (LAMA-ICS), or triple therapy (LAMA + ICS + LABA) and collected patient characteristics such as age, sex, history of exacerbations, and comorbidities at the start of each treatment period.

The investigators used a Poisson regression analysis to calculate the relative rate (RR) of severe asthma exacerbations, adjusting for patient characteristics.

The researchers sought main outcome measures of the relative rate of severe exacerbations, measured by oral corticosteroid use, emergency department visits or hospitalizations for asthma.

A total of 3596 LAMA treatment periods were identified, 1390 (38.7%) of which were considered LAMA monotherapy, 553 (15.4%) of which were double therapy, and 1653 (46.0%) were triple therapy.

For all the patients using LAMA treatments, the relative rate of severe asthma exacerbations during monotherapy compared to double therapy was 1.58 (95% CI, 0.52-4.77; P = 0.18). After excluding patients who used triple therapy, the relative rate increased to 5.72 (95% CI, 1.39-23.62; P = 0.016).

In comparisons, for patients in the triple therapy group, the relative risk was 3.17 (95% CI, 1.09-9.16; P = 0.033).

“This observational study shows that LAMA is frequently prescribed as monotherapy (i.e. without concurrent ICS) which is associated with an increased risk of exacerbations,” the authors wrote. “This emphasizes the need to check for ICS use when prescribing LAMA to asthmatic patients.”

Recently, investigators found 1 way to reduce severe asthma exacerbation rates was dupilumab.

The investigators obtained data from the phase 3 QUEST and phase 2b studies to identify 3 subgroups of patients with baseline blood eosinophil count, inhaled corticosteroids dose, and number of severe exacerbations that matched the key inclusion criteria of clinical trials of anti-IL-5 biologics.

The team found dupilumab 200 mg and 300 mg every 2 weeks significantly reduced the annualized severe exacerbation rate in all 3 subgroups versus the standard of care. The exacerbation rate ratio for each subgroup was .26 (95% CI, .21-.33), .36 (95% CI, .29-.44), and .29 (95% CI, .23-.36), respectively, which represented a 64-74% relative exacerbation rate reduction.

The study, (in)Appropriate LAMA Prescribing in Asthma patients: a Cohort Analysis (the ALPACA study), was published online by ERS 2020.