FDA narrows label for Abiomed's Impella RP heart pump after mortality rose in post-approval study

After Abiomed’s attempts to expand the user pool for its Impella RP heart pump were less than successful, the FDA has updated the wording of the device’s label to direct it toward only the patients who may benefit most.

The pump is designed to treat people with right-sided heart failure. Once implanted into the right side of the heart, it pumps blood from the body’s largest vein, the vena cava, through the heart and into the pulmonary arteries leading to the lungs. The system is controlled using an external console that connects to the pump via catheter, and it’s meant to be used for up to 14 days.

The FDA first cleared the Impella RP system in 2017. Since then, the technology has landed an emergency use authorization to help treat COVID-19 patients with right heart failure, as well as regular-use nods for new versions of the pump that integrate optical sensors and can be implanted through the jugular vein, rather than the thigh’s femoral vein.

Abiomed Impella RP

After its initial clearance, Abiomed launched a post-approval study mandated by the FDA. Though the study kept the same primary endpoint as the device’s premarket clinical studies, it included a wider range of real-world patients than those that qualified for the premarket studies’ strict inclusion and exclusion criteria.

In interim results of the post-approval study that were released in 2019, Abiomed reported that the Impella RP system’s mortality rate shot up among the broader patient group, per a now-archived letter from the FDA to healthcare providers. At the time, the agency asked Abiomed to provide doctors with more information about the patients who would benefit the most from the pump and to expand its subgroup analyses in the post-approval study.

In the premarket studies, the use of the heart pump had resulted in a survival rate of 73.3%. That rate was consistent among participants in the postmarket study who matched the premarket criteria but sharply plummeted among a subgroup of patients who were treated with the device but wouldn’t have qualified for the premarket studies.

Of the 70 patients in the latter group, only 13 lived to either 30 days after the treatment or to the start of a longer-term therapy, for a survival rate of 18.6%, according to the final results of the study, which Abiomed reported to the FDA in August. Meanwhile, patients who met the premarket eligibility criteria experienced a survival rate of just under 70%.

Thanks to those findings, the FDA has now narrowed the scope of the Impella RP system’s indications for use. According to a Monday update, the label now recommends it be used only in patients who have been experiencing acute right heart failure or decompensation for less than 48 hours before the implant procedure; the original label didn’t specify a time limit for cardiogenic shock.

The new label also specifies that implants of the heart pump be limited to patients who haven’t experienced profound shock, end organ failure or acute neurologic injury alongside their right-sided heart failure—another qualification that wasn’t listed in the original indication.

In a statement sent to Fierce Medtech, a spokesperson for Abiomed said, "We are excited about the indication change, which aligns with best practices and how Abiomed has been training physicians to use Impella RP for several years."

Editor's note: This story was updated to include a statement from Abiomed.