On April 26, the U.S. Food and Drug Administration (FDA) approved a new device that may increase access to more lungs for transplant. The new Xvivo Perfusion System (XPS) with Steen Solution Perfusate is a type of ex vivo lung perfusion (EVLP) therapy, which can temporarily ventilate and pump preservation solution through lungs.

The process can increase the percentage of lung transplants by allowing transplant teams to identify better quality lung grafts that would have been otherwise rejected for transplantation in the past.

The EVLP device allows transplant teams to pump preservation solutions through the lungs outside of the body. This allows the team to perform a careful assessment of lung function and determine whether the lungs are viable for transplant.

The FDA originally granted the Xvivo Perfusion System in 2014 under a humanitarian device exemption (HDE), which limited use of the device to a maximum of 8,000 patients per year. Approval removes this yearly restriction, which allows for a greater number of lungs to be available for transplant. FDA approval could also increase the number of patients benefiting from this technology.

Lung transplantation is the only known lifesaving treatment for end-stage lung disease, but many patients do not survive long enough to receive a viable organ. Surgeons performed approximately 2,530 lung transplants in 2018, according to the U.S. Department of Health and Human Services.

The number of lung transplants is significantly lower than the number of other organ transplants, such as kidney and liver transplants at 21,167 and 8,250, respectively.

The FDA notes that only about 15% of lungs from deceased donors are suitable for transplantation, largely because large number of donor organs have questionable physiological function. A number of factors, such as lung injury, poor lung function and not enough time to find suitable donor-recipient matches can reduce lung function and decrease the number of available organs.

"Sadly, too many patients on transplant lists die waiting for suitable lungs. Providing patients with access to safe medical devices that have the potential to be lifesaving remains a top FDA priority, and we support the development of innovative technologies that can increase the donor organ pool for transplant patients in need of suitable lungs," said Benjamin Fisher, Ph.D., in the statement issued by the FDA. Fisher serves as Director of the Division of Reproductive, Gastro-renal and Urological Devices at the FDA’s Center for Devices and Radiological Health.

About the Xvivo Perfusion System

The Xvivo Perfusion System allows transplantation teams to ventilate, oxygenate and perfuse lungs at a standard normal body temperature for up to five hours. This gives surgeons enough time to assess suitability and even allows them to transplant some lungs initially determined to be unsuitable.

The device features a perfusion cart with electrical and mechanical components that ventilate, oxygenate and pump lung preservation solution through the lungs.

Prior to granting approval, investigators from the FDA evaluated data from a study in which researchers allocated 332 sets of donor lungs into three groups. Lungs immediately deemed suitable for transplant served as the control group; these lungs were provided to 116 recipients after standard preservation.

The second group included lungs initially deemed unsuitable for transplant, but determined to be suitable after perfusion with the Xvivo Perfusion System; these lungs were transplanted into 110 recipients. Lungs in the third group were still not suitable after perfusion with XPS, and therefore not implanted into patients.

At 94% for recipients in the control group and 86.4% for the lung perfusion patients, the difference in one-year survival rates between the two groups was clinically insignificant. The most common adverse events associated with the Xvivo Perfusion System include acute rejection, infections, bronchial complications, and respiratory failure.