Fexlamose, an inhaled thiol-based therapeutic agent designed to liquify mucus plugs by cleaving the chemical disulfide bonds that thicken mucus, failed to meet its primary and secondary endpoints in a phase 2a proof-of-concept trial.
Aer Therapeutics Inc., the company behind fexlamose, said in a news release that the treatment did not demonstrate:
- Improvement on trough forced expiratory volume in one second (FEV1), forced vital capacity (FVC) or other spirometric measures within 28 days of dosing in moderate-to-severe COPD patients
- Overall reduction from baseline in Mucus Plug Segment Score (MPSS) — an imaging biomarker measuring pharmacodynamics, target engagement and efficacy
In addition, the company said most respiratory adverse events, including COPD exacerbations, occurred among those dosed with 90 mg of fexlamose, and treatment discontinuation was more frequent among patients receiving fexlamose than placebo.
The trial, “A Study to Investigate Using Inhaled Fexlamose to Treat Adult Participants Who Have Moderate to Severe COPD (AER-01-002),” was a randomized, double-blind, placebo-controlled parallel group study designed to evaluate the efficacy and safety of fexlamose compared to placebo. It was conducted in Australia, New Zealand, United Kingdom, Poland, Spain and Bulgaria with 119 moderate-to-severe COPD patients.
John Fahy, MD, MSc, founder and chief clinical consultant of Aer Therapeutics, said that while the company was disappointed with the overall results of the trial, some good information did come from it.
“Although the primary endpoint was not met, the study yielded high-value data that will advance our understanding of mucus plug pathology in COPD and other lung diseases,” said Dr. Fahey, who is also a professor in the division of pulmonary, critical care, allergy and sleep medicine at the University of California, San Francisco.
