A temporary heart pump manufactured by Massachusetts-based Abiomed prompted a US Food and Drug Administration letter to health care providers on Monday over an increased rate of mortality.
The letter cites interim results from Abiomed’s January report on a post approval study (PAS) that was mandated by the agency as a condition for the 2017 FDA approval of the Abiomed Impella RP System.
“A total of 44 out of 60 patients (73.3%) survived to 30 days post device explant or hospital discharge or to the state of the next longer term therapy” when “strict inclusion and exclusion criteria” were followed in the premarket clinical studies Abiomed conducted to seek approval, FDA said. “Interim results from the most recent PAS report, which reflect device use in a broader patient population, indicate that only 4 out of the 23 enrolled PAS patients (17.4%) met the primary survival endpoint.”
The interim PAS results signals an increased mortality rate among Impella RP heart pump recipients. Yet the device—implanted in patients who need temporary emergency support to stabilize heart function—has not be subject to a recall. FDA said it is “concerned about the high mortality rate from the interim PAS results,” but believes that the benefits continue to outweigh the risks when the Impella RP system is “used for the currently approved indication in appropriately selected patients.”
The variation in the mortality rates was attributed to different characteristics of pre- versus post-market patients prior to receiving the Impella RP. PAS patients “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,” FDA said. The agency’s probe into this safety issue is ongoing and the root cause of the high mortality rate remains unknown.
In a statement Abiomed provided to Focus
, the company said that the data from the PAS "is an issue of patient selection (not following the proper inclusion/exclusion criteria) and implant timing (not using the device early enough)." The Impella RP heart pump is the only device with FDA premarket application approval for right side support, according to Abiomed's statement. Abiomed sent a letter
to notify physician users about its PAS data last week and FDA's letter followed on Monday, company spokesperson Tom Langford told Focus
The letter comes at a time when FDA’s Center for Devices and Radiological Health (CDRH) has made strides toward a new paradigm in which to strike the right balance between pre- and post-market data collection, including the 2019 plan
for the National Evaluation System for health Technology Coordinating Center to serve as the “front door” to conduct real-world evidence studies.
Abiomed’s PAS “is doing exactly what post-approval studies are designed to do—provide more information about a device’s benefit-risk profile by studying the performance and outcomes of device use in real-world clinical settings,” CDRH Director Jeff Shuren said
in reaction to the letter. “We’re committed to early, transparent communications with health care providers and patients when safety signals emerge and we’ll continue to communicate about this issue as we learn more,” Shuren said.