A Randomized, Placebo-Controlled, Double-Blind Pilot Study of Pioglitazone Hydrochloride in Severe, Refractory Asthma

Overview

Background: \- Individuals who have severe asthma that is not easily controlled by current treatments are in need of new treatments to prevent potentially life-threatening asthma attacks. Experiments in mice have found that a medication called pioglitazone hydrochloride (Actos ), which is used to treat patients with diabetes, may be effective for treating severe asthma. Researchers are interested in determining whether Actos is effective in improving the quality of life in subjects with severe asthma who continue to have symptoms despite maximum standard medical therapy. Objectives: \- To assess the effectiveness of pioglitazone hydrochloride as a treatment for patients with severe asthma that is not controlled by standard treatments. Eligibility: \- Individuals between 18 and 75 years of age who have been diagnosed with and treated for severe asthma for at least 1 year. Design: * Potential participants will have a screening visit to determine eligibility for the study. The visit will involve breathing tests, chest x rays, heart and lung monitoring, and blood tests. * Eligible participants will have a full medical history and will answer a series of questionnaires about their quality of life with asthma. * Phase 1: Patients will record lung function and asthma symptoms morning and evening for 4 weeks. At the end of this period, patients will be evaluated with breathing, allergy, and blood tests, as well as questionnaires. Patients will also provide a sputum sample. * Phase 2: Patients will receive regular doses of either pioglitazone hydrochloride or a placebo for 16 weeks. Patients will return to the National Institutes of Health every 4 weeks for tests. * Phase 3: Wash-out period without study drugs for 4 weeks, similar to Phase 1. * Phase 4: Patients will receive regular doses of either pioglitazone hydrochloride or a placebo for 16 weeks. Patients who received placebo will be given the study drug, and vice versa. Patients will return to the National Institutes of Health every 4 weeks for tests. * Phase 5: Medications will be stopped, and patients will return to the National Institutes of Health 4 weeks later for final tests.

New therapies are needed for patients with asthma who are sub-optimally controlled by standard measures. Pioglitazone hydrochloride (Actos ) is a highly selective and potent agonist for the peroxisome proliferator-activated receptor-Gamma (PPAR Gamma). Studies in murine models of allergic asthma have shown that PPAR Gamma agonists down-regulate allergen-mediated airway inflammation and airway hyperresponsiveness. This protocol is a randomized, placebo-controlled, doubleblind, crossover (phase II) pilot study of the efficacy of pioglitazone for the treatment of patients with severe, refractory asthma. The primary end-point for this study will be quality of life as determined by the Asthma Quality of Life Questionnaire (AQLQ) score. Secondary end-points will include indices of airway inflammation, airflow obstruction, airway hyperreactivity, and asthma symptoms.