Survival rates have been dramatically poorer in the post-approval study for the Abiomed Impella RP right ventricular assist device relative to the device’s clinical trial data, the FDA warned Monday in a “Dear Doctor” letter.
An interim analysis of the mandated post-approval study showed that, whereas 73% of temporary mechanical circulatory support device users survived at least 30 days in the premarket RECOVER RIGHT study, now just 17% have met this primary survival endpoint since the Impella RP went on the market in 2017.
While there is no root cause yet for the unexpected mortalities in this 60-person study, it should be noted that the postmarket study population was worse off at baseline, the agency said in the letter.
“Specifically, before being implanted with the Impella RP system, patients in the post-approval study were more likely than patients in the premarket studies to have been in shock for longer than 48 hours, experienced an in-hospital cardiac arrest, had an intra-aortic balloon pump, or had a stroke or lack of blood flow to the brain.”
The agency recommended that any treatment decisions regarding the Impella RP be taken with consideration of these patient characteristics, and that healthcare providers discuss the benefits and risks of the device with patients and their caregivers.
“The FDA believes that when the device is used for the approved indication in appropriately selected patients, the benefits of the Impella RP system continue to outweigh the risks,” according to the letter.