A pilot trial exploring the use of Abiomed‘s (NSDQ:ABMD) Impella heart pump as a treatment for reducing the severity of heart attacks has met its primary safety and feasibility endpoints, clearing the way for a pivotal trial, according to primary investigator Dr. Navin Kapur.
Results from the pivotal, if successful, could “change the paradigm of heart attack management,” Kapur told MassDevice.com in an interview.
Data from the pilot trial were announced today at the AHA Scientific Sessions 2018 in Chicago.
“We’ve now demonstrated for the first time that [left ventricle] unloading, using the ImpellaCP device with a 30 minute delay before reperfusion is safe and feasible,” Kapur said, commenting on the pilot trial. “What we also learned was that among patients who have larger heart attacks, there was a significantly lower infarct size.”
Even more importantly, the treatment could improve outcomes for heart failure patients.
“If we can change infarct size by 5%, we think that this will reduce the global burden of heart failure due to heart attacks and will also improve not only short term mortality, but improve long term mortality for patients who are coming in with a heart attack. And that’s really the central goal of both the pilot and the pivotal trial,” Kapur said.
For every 5% increase in heart damage after a heart attack, there’s a relative 20% increase in heart failure hospitalization at one year, and a 20% increase in mortality, Kapur said.
“There’s a significant need in public health for trying to reduce heart attack size for patients who are coming in, despite using contemporary approaches,” Kapur said.
Blocked arteries reduce the amount of oxygen supplied to the heart, Kapur said, so in normal treatment, opening the arteries to improve myocardial oxygenation has been a primary concern. But previous research has suggested that instead of simply restoring oxygen supply by opening arteries, myocardial oxygen demands could also be lowered through reperfusion, or reducing the work the heart has to do – with something like Abiomed’s Impella pump.
In his own research, Kapur said that he’s found that reperfusion works best with a 30 minute delay, leaving the device in and functioning while the arteries are blocked, before opening any arteries.
“We’ve spent the last six to eight years understanding the mechanism for why delayed reperfusion in the setting of an unloading pump seems to work. And there’s a number,” Kapur said.
Kapur and he and his team published research in the Journal of the American College of Cardiology in August exploring the mechanism, and that the pilot study aimed to explore the safety and feasibility of the technique.
In the pilot trial, dubbed The Door to Unload, researchers explored the mechanical benefit of delayed reperfusion in treating patients who suffered from a heart attack. Investigators enrolled a total of 50 patients, half of which received left ventricle unloading with the Impella followed by immediate reperfusion, while the other half received a 30 minute delay to reperfusion, Kapur said.
Safety endpoints in the trial included any increase in major adverse cardiovascular or cerebrovascular events and an increase in infarct size amongst those in the delayed reperfusion arm.
Results from the phase one safety and feasibility trial indicated a 100% successful implantation and unloading rate with the Impella, Kapur said.
Data indicated no significant difference the rate of major adverse cardiovascular or cerebrovascular events among arms, and found infarct size that was smaller than what was seen in previously published studies. Delaying reperfusion had no effect on infarct size either, Kapur said. Patients were examined at three to five days and thirty with cardiac magnetic resonance imaging, he added.
An additional analysis, which explored patients who experienced larger heart attacks, found that unloading and delayed reperfusion resulted in a statistically significantly lowered infarct size, normalized to the area of risk, as compared to unloading and immediate reperfusion.
“And the reason why this is important is because the purpose of the pilot was to inform the development of the pivotal study,” Kapur said.
The pivotal is slated to compare standard-of-care treatment, which takes into consideration only door-to-balloon time, against patients treated with delayed reperfusion using the Impella pump.
Kapur said he believes that results from the trial, if successful, could be disruptive, as it could suggest that unloading treatment with the Impella device is a therapy in itself.
Beyond the pivotal, Kapur said he sees a lot of opportunity to explore other angles, including other therapies or treatments to engage in during the 30 minute delay.
“What do you do during those 30 minutes? Do you give drugs that would potentially be more beneficial in reducing infarct size?” Kapur said.
Earlier this month, Abiomed posted fiscal second-quarter numbers that shredded the consensus forecast and raised its outlook on the rest of the year, sending share prices up sharply today.
