129Xe MRS Biomarkers Predict 6-week Response to ICS/LAMA/LABA in Moderate Asthma

Motivation: 129Xe MRS quantifies pulmonary gas-exchange by probing inhaled 129Xe transfer from the alveolar-membrane to the red-blood-cells (RBC). Recent work suggested a vascular response to asthma therapy, quantifiable using 129Xe MRS. Goal(s): We aimed to examine if 129Xe MRS measurements were predictive of significant 6-week response to ICS/LAMA/LABA in moderate asthma patients. Approach: 129Xe MRS and pulmonary function measurements were acquired prior to and following 6-weeks of therapy. Results: 129Xe RBC:membrane, measured prior to treatment, was predictive of response to ICS/LAMA/LABA at 6 weeks, measured using the fraction-of-exhaled nitric-oxide and the ratio of forced-expiratory-volume in 1-second to forced-vital-capacity. Impact: For the first time, 129Xe MRS RBC:membrane has been shown to predict early (6-week) response to ICS/LAMA/LABA in moderate asthma. 129Xe MRS uncovered a novel pathophysiology in asthma patients, with potential for consideration as a new treatable target.