Results from the randomized, multi-center LIBERATE clinical trial (NCT01796392) are expected to support approval of the device by the U.S. Food and Drug Administration (FDA).
The LIBERATE trial enrolled 190 patients in 24 centers to assess Zephyr EBVs’ safety and effectiveness versus optimal medical management, with patients randomized at 2:1 ratio (Zephyr EBV vs. control group).
The trial’s primary objective is to evaluate lung function, measured by forced expiratory volume in one second (FEV1) at one year. Secondary outcomes are volume reduction of the treated lobe of the lung, improvement in exercise capacity (assessed through the six-minute walk distance, or 6MWD, test), and changes in quality of life assessed through the St. George’s Respiratory Questionnaire (SGRQ).
Severe emphysema is a form of chronic obstructive pulmonary disease (COPD) that refers to an abnormal permanent enlargement of the distal airspace and the terminal bronchioles, along with the loss of elasticity of alveolar walls and the supporting structures feeding the alveoli.
Emphysema eventually reduces a patient’s capacity to inhale and exhale air, and reduces the overall surface area for gas exchange.
Zephyr EBVs are small, minimally-invasive, one-way valves that are placed in selected airways of the lungs to occlude damaged regions and reduce lung hyperinflation. This process results in a more efficient functioning of the remaining healthier lung regions, enabling improved breathing capacity and a higher quality of life.
Studies like “Predicting Lung Volume Reduction after Endobronchial Valve Therapy Is Maximized Using a Combination of Diagnostic Tools,” published in the scientific journal Respiration, have shown that over 50% of severe emphysema patients have no collateral ventilation in one or more target lobes of the lung, which demonstrates a large potential market for Zephyr EBV.
“The Zephyr EBV is the most studied endoscopic lung volume reduction device globally and is considered first-line therapy by leading physicians outside of the U.S.,” Pulmonx CEO Glen French said in a press release. “Completing enrollment in this important trial moves us one step closer to making this proven treatment available to U.S. patients who have few options today.”
Three previous randomized clinical trials of Zephyr EBV, conducted outside the United States – BeLieVeR-HIFi (ISRCTN04761234), STELVIO (NTR2876), and IMPACT (NCT02025205) – have shown that the device was capable of significantly improving emphysema patients’ lung function, exercise tolerance, and quality of life in cases where there was no collateral ventilation, as assessed by the Chartis System.
Other published data (a full list is available in the press release) has also indicated that Zephyr EBV leads to sustained patient benefits up to five years, and potential survival benefits at five and 10 years after treatment, indicating a potential deceleration of disease progression. Over the past decade, more than 40,000 Zephyr EBVs were implanted globally in over 12,000 patients.
Here is an informational video of the full Zephyr EBV procedure: