LOS ANGELES – Once-daily tiotropium bromide inhalation spray as long-term, add-on maintenance therapy in patients with poorly controlled symptomatic asthma is similarly effective in both allergic and nonallergic asthma, according to Dr. Donald P. Tashkin.
In a series of analyses presented at the annual meeting of the American Academy of Allergy, Asthma, and Immunology, he and his coinvestigators showed that tiotropium bromide inhalation spray (Spiriva Respimat) given as add-on maintenance therapy resulted in significantly improved lung function, enhanced asthma symptom control, and fewer asthma exacerbations. The important new finding in these post hoc analyses was that the medication was similarly effective across the full range of baseline serum IgE and blood eosinophil levels, said Dr. Tashkin, director of the pulmonary function laboratories at the University of California, Los Angeles.
Last fall, the Food and Drug Administration approved an expanded indication for tiotropium bromide inhalation spray as long-term, add-on maintenance therapy of asthma in patients aged 12 and up who remain symptomatic despite taking other maintenance therapies. The once-daily medication had already been approved in the fall of 2014 for maintenance therapy of chronic obstructive pulmonary disease. Spiriva Respimat delivers a once-daily 2.5-mcg dose of tiotropium bromide via two 1.25-mcg puffs in a slow-moving, propellant-free mist designed to get the drug into the distal lungs independent of a patient’s skill in using a conventional metered-dose inhaler.
Dr. Tashkin and his coinvestigators presented a series of post hoc analyses combining data on 3,012 participants in the two prospective PrimoTinA-asthma and two MezzoTinA-asthma clinical trials. These phase III, double-blind, placebo-controlled trials defined participants’ allergic phenotype on the basis of the conventional cut points of a serum IgE level above or below 430 mcg/mL or a blood eosinophil count above or below 600 cells/mcL.
“The question is, are these appropriate cut points? Can we be sure that somebody below those cut points doesn’t have atopy? To answer that question, we looked at the whole spectrum of eosinophils in the blood from 5/mcL to 2,000/mcL and serum IgE levels from 2 mcg/mL to 2,000 mcg/mL. We found that the efficacy was similar across the entire spectrum of these measures of allergy,” he said in an interview.
Thus, these new findings support the use of this novel maintenance therapy without any need for lab tests to determine whether an individual patient’s asthma is T helper 2–cell dominant or not, Dr. Tashkin added.
The PrimoTinA-asthma trials were 48-week studies of add-on Spiriva Respimat or placebo conducted in patients with symptomatic asthma despite treatment with an inhaled corticosteroid plus a long-acting beta-agonist. The MezzoTinA-asthma studies were 24 weeks long and focused on patients who remained symptomatic despite at least moderate-dose inhaled corticosteroid therapy. Key endpoints included improvement in asthma symptom control as measured by the seven-question Asthma Control Questionnaire, improved peak and trough forced expiratory volume in 1 second, and time to a first severe asthma exacerbation.
Dr. Tashkin reported serving as a paid speaker on behalf of Boehringer Ingelheim, which markets Spiriva Respimat and sponsored the studies.