Disc Dynamics (Eden Prairie, Minnesota) is on a quest for pre-market approval (PMA) of its “novel concept” in its DASCOR Disc Arthroplasty System for the treatment of degenerated lumbar discs, and the FDA just gave the company a green light for the first step on that regulatory path.

The agency gave the company approval to initiate what will be a 20-patient pilot trial, and CEO Steven Healy said he expects enrollment in the study to take until the end of 2006, with patients then to be followed for one year.

The technology is a catheter-based, minimally-invasive nucleus replacement technology, otherwise known as a partial disc replacement system.

Although the company received CE mark approval for commercial sale of the technology in July 2005, Healy told Medical Device Daily: “We've got an approval in Europe, but we've just continued to do a post-market approval study, and in 2007 we will begin commercialization efforts.”

He said the distinguishing aspect of the DASCOR Disc Arthroplasty System is that the procedure can be carried out percutaneously – just as in some interventional cardiology strategies – through about a half-centimeter incision, thus avoiding the open procedure required in fusion surgeries.

“The concept for this system is to go in through a very small hole and to be able to deliver a very large implant,” Healy said.

Using a “series of micro-instruments” developed by Disc Dynamics, “the surgeon goes in and removes the diseased nucleus material,” he said. The company also uses imaging during the surgical procedure to make sure that “the appropriate amount of material is removed” from the nucleus area.

The device itself involves a balloon on the end of a catheter, with the balloon then filled with “a liquid polymer under pressure” to ensure that the entire area where the diseased nucleus was located is filled – all toward the goal of returning a patient to “normal disc height.”

“Our goal is either to maintain or increase disc height,” Healy said. “And then this material that goes in as a liquid solidifies in just a few minutes.”

The catheter is cut off, and “then, in essence, the patient receives a custom implant,” because the liquid molds itself to and fills the empty space.

Healy said the product – which was originally developed by Advanced Bio Surfaces (Minnetonka, Minnesota) and then spun off in 2000 as Disc Dynamics – is a totally “novel concept” and that there is nothing similar to it on the market. It is, he said, “an incredibly minimally invasive procedure.”

In the post-market studies conducted on 15 to 20 patients in Europe, Disc Dynamics now has “close to two years of follow-up” post-implant.

“We've seen significant pain reduction, significant functional improvement, and importantly, significant reduction in analgesic use,” Healy told MDD. Recovery times have been good in the European study, but he said “the U.S. will be its own market in terms of hospital stay times,” because in Europe, there has been an emphasis in the healthcare system in keeping patients in the hospital for recovery.

The DASCOR system is Disc Dynamics' primary product.

Healy joined the company in July 2002, which also was when the company raised its “first significant money.” A little over two years ago, Disc Dynamics raised $24 million. It is now in the process of raising an additional round of funding.

Healy said the company is planning to raise enough money “to carry us until PMA approval,” and he expects the pathway to pre-market approval, if all goes as planned,to take four to five years.

The planned funding will be used to develop fully the percutaneous delivery method for the DASCOR implant.

In other news coming from this sector, DePuy Spine (Raynham, Massachusetts) last week reported the first successful implant of its investigational Discovery Artificial Cervical Disc in eight patients with single- and two-level degenerative disease.

The Discover disc consists of a ball-and-socket design constructed from titanium and polyethylene.

The company said that the surgeries “mark the beginning” of a multi-center randomized clinical trial designed to evaluate the safety and effectiveness of the device in patients with single and two-level degenerative disc disease, calling it a common cause of neck and arm pain.

As many as 30 centers will participate in the trial, with the data from that trial scheduled to be submitted to the FDA for approval of the device.

The study will evaluate if the Discover Artificial Cervical Disc relieves pain, maintains or improves range of motion, restores disc height, has an effect on adjacent level disease and provides biomechanical stability as compared to spinal fusion surgery, the standard of treatment for degenerative disc disease of the upper spine.