Medical Device Daily Associate

Another company took a step towards a U.S. approval for a ventricular assist device (VAD) yesterday when it reported an FDA approval for its pivotal trial.

Jarvik Heart (New York) – the company whose namesake, Robert Jarvik, MD, invented the original artificial heart implanted in Barney Clark more than 20 years ago – said yesterday that it has received full approval from the FDA to begin a pivotal trial of the Jarvik 2000 FlowMaker, for bridge-to-transplant use, with an eye towards ultimate approval of the device as a destination therapy.

The pivotal study is designed to establish the safety and efficacy of the Jarvik 2000 in supporting severe heart failure patients while they await the availability of a donor heart for transplant.

In Europe, the Jarvik 2000 has earned the CE mark for both bridge-to-transplant and destination therapy, and has been supporting its first lifetime-use patient for more than five years with what the company called “an excellent quality of life.”

Later this year, the company said it plans to submit an application to the FDA for a pivotal study of the Jarvik 2000 for use as a destination therapy in the U.S. under a protocol designed for the treatment of heart failure in earlier-stage patients. The company said that using the mechanical heart earlier – before patients suffer too much damage to other organs – is expected to help them recover more rapidly to a normal life.

According to Jarvik, while a bridge-to-transplant approval may help some patients, that clearance is merely a stepping stone towards the more important use for a VAD.

“The thing that is needed in a public health sense is a long-term, heart-assist device that is really simple and [provides] a good quality of life for people,” he told Medical Device Daily.

He noted that his company’s emphasis is different from the majority of other players in this sector.

“We’re trying to introduce treatment for the sake of relieving the symptoms of severe heart failure. Most efforts have been solely towards extending life” after patients had already reached a critical stage where the device is largely a last minute rescue device. He said VADs “should be used earlier for lifetime use or for very long-term bridge-to-transplant type of use that we have named maintenance therapy.”

Up to 160 patients will be enrolled in the pivotal study at 25 medical centers throughout the U.S.

Presently, the company reports nine “trained” implant centers, and that 16 additional implant teams will be added over the next year. In addition to the survival rate to transplant, the study will examine patient quality of life and rates of serious adverse events, the company said.

The launch of the pivotal study follows completion of a pilot study of the Jarvik 2000 in the U.S., which enrolled 63 patients at eight medical centers. Many of those patients are surviving up to five years following implant of the mechanical heart and subsequent transplant.

The company said that the pilot study yielded other important data, as well, including very high reliability with no failures of the implanted Jarvik 2000 and rates of infection, thromboembolism and stroke the same or lower than those reported in the literature for currently FDA-approved heart assist devices, Thoratec’s (Pleasanton, California) HeartMate and WorldHeart’s (Oakland, California) Novacor.

The Jarvik 2000 also compares favorably with the HeartMate and Novacor in other ways, the company said. It weighs only 90 grams, compared to 1,200 grams for HeartMate, and 1,800 grams for Novacor.

Unlike the natural heart, the Jarvik 2000 pump does not “beat.” Instead, it uses a spinning rotor to propel blood from the left ventricle into the aorta. This allows the device to be silent, whereas the HeartMate and Novacor produce noises that can be heard by the patient and others nearby.

And because the Jarvik 2000 is a true “booster” pump, the patient’s natural heart continues to work in tandem with it. Therefore the device requires less power and achieves long battery life.

With its small size – about that of a human thumb – the device can be implanted inside the left ventricle of the biological heart. The pump is inserted through a circular incision in the heart wall and secured with a polyester sewing cuff. A fabric tube from the outflow end of the pump connects it to the aorta.

Still another benefit, said Jarvik, is the very low rate of infection shown by the pump, accomplished via an interface with external components by means of connection to a “post, behind the ear.” This location appears to be much more resistant to infection than sites in the abdomen, he said, a discovery he made through his work with cochlear implants over the past 20-plus years.

The Jarvik 2000 also gives patients the unique ability to manually control the output of the device via a small, external controller.

Unlike the natural heart, the company said that these mechanical devices do not “know” with certainty when patients exert themselves and need more oxygen-rich blood to the muscles; nor do they know when patients are sleeping and need less.

The company believes that the manual-control approach of the Jarvik 2000 remains the safest approach to regulating a VAD. Some other heart rotary assist devices have automatic control systems in which a computer determines the speed of the pump.

While this works in some circumstances, the company noted that there can be situations in which the computer can make a mistake and run the device at a dangerous speed because it does not have enough information about the patient’s condition.

Jarvik 2000 patients receive guidelines for making adjustments to the pump’s speed, but over time, they learn to adapt the settings to their individual health conditions.

In an interview last year with MDD, Jarvik said he wasn’t in a huge hurry to earn U.S. approval (Medical Device Daily, Aug. 17, 2004). Rather, he said that slow, purposeful development of solid clinical data is the primary foundation for the larger goal: “to do well for the initial patients – to let them have a long and good life.”

Returning to the present, Jarvik said that other companies in the space have talked about hundreds of thousands of patients that can be treated with VADs in the next decade. Those numbers, he said, “are just not real. What is real is steady growth, steadily proving the technology and seeing something that has an increasing importance in terms of treating these kinds of patients.

“You have to look at a longer horizon to see this becoming something that is like a pacemaker that’s everywhere.”

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