The FDA approved a new medical device for patients suffering from severe emphysema. The Pulmonx Zephyr Endobronchial Valve is a one-way valve system to be implanted through the airways using a traditional bronchoscope. The valve is integrated into a stent that expands against a bronchiole to block off air flowing in and only allow it to flow out. As the trapped air flows out, ventilation/perfusion mismatch is improved, and the device relieves pressure on the healthy lung to allow for better breathing.
The available data is from a multi-center study of 190 patients with severe emphysema (the LIBERATE trial), comparing Zephyr plus standard-of-care to standard-of-care only (bronchodilators, corticosteroids, antibiotics, and anti-inflammatories) in a 2:1 allocation ratio. 47.7% of patients that received the Zephyr saw ≥15% improvement in their pulmonary function, compared with 16.8% of patients in the standard-of-care group. Furthermore, patients who received the Zephyr had a higher FEV1 (they could forcibly exhale more air), quality of life, and 6 minute walk distance, suggesting a clear benefit to using the valve. Adverse events of the procedure included death, collapsed lung, pneumonia, worse emphysema, coughing blood, shortness of breath, and chest pain.
At its heart, the Zephyr is a mechanical solution to a mechanical problem. Emphysema is an irreversible chronic obstructive pulmonary disease (COPD) characterized by restrictive airflow and low diffusing capacity. Outflow is reduced so diseased alveoli build up air like a balloon and enlarge continuously. This results in ciliary dysfunction, mucus build up (due to damage to the cilia that now can’t sweep and clear mucus), and compression of nearby healthy alveoli that cause further airflow obstruction. Ultimately, it causes a lack of oxygen and constant breathlessness that makes all daily activities difficult. The one-way valve of the Zephyr relieves the built up air and restores lung function. It represents a less invasive treatment for these severe emphysema patients that are unresponsive to other therapies, and that would otherwise be considered for lung volume reduction or lung transplants.
The Zephyr was designated as a Breakthrough Device and followed the FDA’s premarket approval pathway for Class III medical devices.