FDA has approved a new device intended to treat breathing difficulty associated with severe emphysema. The approval comes just two weeks after an FDA advisory panel shot down a competing technology targeting the same patient population.
The agency approved Pulmonx Inc.'s Zephyr endobronchial valve through the breakthrough device designation, a pathway reserved for devices that provide for more effective treatment or diagnosis of a life-threatening or irreversibly debilitating disease or condition. Devices also must meet one of the following criteria: the device must represent a breakthrough technology; there must be no approved or cleared alternatives; the device must offer significant advantages over existing approved or cleared alternatives, or the availability of the device is in the best interest of patients.
"I can really only sing the praises of FDA in this case," Beran Rose, vice president of marketing and business development at Pulmonx, told MD+DI.
Not only did the agency grant the company a breakthrough device designation for the Zephyr, but the product was approved in less than six months, Rose said. One of the advantages of qualifying for the breakthrough device designation is that FDA provides intensive interaction and guidance to the company on efficient device development, to expedite evidence generation and the agency's review of the product.
FDA also did not require an advisory panel prior to making its decision. BTG wasn't so lucky. In June, an FDA advisory panel voted against BTG's Elevair endobronchial coil system for the treatment of people with severe emphysema. The panel determined that the Elevair system is safe, but raised concerns about its effectiveness and whether or not the benefits of the system outweigh the risks.
That's not to say that the agency wasn't as thorough with its review of the Zephyr valve.
"FDA asked a lot of hard questions and I think we had a really well-executed series of studies, not just one but multiple clinical trials, and we were able to quickly answer whatever questions FDA had," Rose said. "This wasn't just the phenomenon of one trial."
It probably didn't hurt that the device is also already included in most of the major international treatment recommendations for chronic obstructive lung disease (COPD), which emphysema falls under the umbrella of, Rose said.
“Treatment options are limited for people with emphysema who have severe symptoms that have not improved from taking medicines. These have included lung surgery, such as lung volume reduction or lung transplants, which may not be suitable or appropriate for all patients,” said Tina Kiang, PhD, acting director of the Division of Anesthesiology, General Hospital, Respiratory, Infection Control, and Dental Devices, in FDA’s Center for Devices and Radiological Health. “This novel device is a less invasive treatment that expands the options available to patients.”
The Centers for Disease Control and Prevention estimates that 3.5 million American adults have been diagnosed with emphysema, which is a type of COPD, due to damage to the air sacs (alveoli) in the lungs. Lung damage from emphysema is irreversible. The damaged alveoli can cause used air to become trapped in the lungs during exhalation, which can cause the diseased parts of the lung to get larger and put pressure on the healthy part of the lung, making it difficult to breathe.
"People think of it as a problem of not being able to breathe enough air in, but really it's a problem of not being able to breathe enough air out," Rose said.
Lungs are similar to balloons, he explained, in that when you blow air into a balloon the pressure builds inside of it and naturally wants to push the air back out. In a person with healthy lungs, when we breathe air in our lungs open and draw in that air. In people who suffer from COPD or emphysema, their lungs have lost that natural elastic quality so it is more like breathing air into a paper bag.
FDA reviewed data from a multi-center study of 190 patients with severe emphysema. In the study, which MD+DI wrote about in May, 128 patients were treated with Zephyr Valves and medical management according to current clinical guidelines, including medications (bronchodilators, corticosteroids, antibiotics or anti-inflammatory maintenance medications) and pulmonary rehabilitation, while 62 patients received medical management only. Results of treatment were measured by how many patients in each arm of the study had at least a 15% improvement in pulmonary function scores (the volume of air that can forcibly be blown out in one second after full inhalation). At one year, 47.7% of patients treated with Zephyr Valves experienced at least a 15% improvement in their pulmonary function scores, compared with 16.8% of patients in the control group. Adverse events observed in the study include death, air leak (pneumothorax), pneumonia, worsening of emphysema, coughing up blood, shortness of breath, and chest pain.
Patient selection is key to the success of the procedure, and Pulmonx also has a diagnostic test called the Chartis Pulmonary Assessment System that is designed to help doctors assess whether or not the Zephyr technology will be effective for a given patient.