Medical Device Daily Senior

MicroVention (Tustin, California), a subsidiary of Terumo (Tokyo), said it has begun enrolling patients in its Hydrogel Endovascular Aneurysm Treatment (HEAT) trial, designed to compare the use of coiling technologies to treat intracranial aneurysms. The prospective, randomized, international multi-center study will pit the company's MicroVention hydrogel coils against bare platinum coils. The HEAT trial will enroll up to 600 patients from about 30 sites around the world.

Bernard Bendok, MD, a neurosurgeon at Northwestern Memorial Hospital and an associate professor at Northwestern University Hospital (both Chicago), is the principal investigator for the HEAT trial.

“Intracranial aneurysms can be a devastating, life threatening condition with approximately 30,000 people suffering from subarachnoid hemorrhage each year in the USA alone. The HEAT trial will allow us to better understand these lesions and advance their treatment,“ Bendok said.

It is estimated that up to one in fifteen people in the U.S. develop a brain aneurysm during their lifetime. The traditional method of surgical clipping to treat brain aneurysms is very invasive requiring removal of a section of the skull. Since 1995, endovascular coils, have gained popularity, now accounting for the majority of current procedures (Medical Device Daily, July 19, 2011).

The HydroCoil embolic system is a non-bioactive endovascular embolization device combining MicroVention's platinum microcoil technology with a proprietary hydrogel, MicroVention said. The hydrogel polymer is a biomaterial that begins to swell after a brief period of contact with blood, giving physicians the ability to precisely control delivery of the device, the company noted. Once the hydrogel swells, it provides improved filling of the aneurysm without exerting pressure onto the aneurysm wall or adjacent coils. The HydroCoil system combines the safety of platinum coils with the filling and mechanical stability of hydrogel.

MicroVention said the HEAT trial will focus on the newer generations of the HydroCoil Embolic System that are designed for ease of use together with the benefits of hydrogel. The HydroCoil system offers a therapeutic alternative to the current treatment choices of platinum coils and neurosurgical clipping, and is also being used clinically to treat fistula and peripheral vascular lesions.

Nearly two years ago MicroVention reported 18-month follow-up data from an earlier international study, dubbed HELPS, comparing the HydroCoil system to the current standard bare platinum coils for cerebral aneurysms. According to those results, the HydroCoil reduced recurrence and retreatment rates and provided improved outcomes in study patients compared to the bare platinum coils. The HELPS (HydroCoil Endovascular Aneurysm Occlusion and Packing Study) trial showed a statistically significant 8.5% less aneurysm recurrence with HydroCoil than with bare platinum (MDD, Aug. 9, 2010).

“The HEAT trial is intended to provide evidence that our second-generation hydrogel coil technologies provides superior long-term clinical outcomes compared to bare platinum coils,“ said Richard Cappetta, president/CEO of MicroVention. “In a recently published article in the Lancet reporting on our earlier HELPS trial results, MicroVention's first-generation HydroCoil embolic system demonstrated superior angiographic outcomes at 18 months compared to bare platinum coils. We believe that, with a comprehensive line of second-generation hydrogel technologies utilized in the HEAT trial, which includes the HydroFrame, HydroFill, and HydroSoft embolic coils, improvement in clinical efficacy should be even greater compared to bare platinum coils. In addition, these new gel coils are much easier to use due to their increased repositioning time, softer delivery system and standardized microcatheter delivery.“

Terumo merged with MicroVention back in 2006 (MDD, March 1 and March 31, 2006) in an all-cash acquisition, the value of which was not disclosed. At the time of the merger, the companies noted that the worldwide market for the endovascular treatment of cerebral aneurysms was estimated at about $225 million and expected to show double-digit growth over the next several years.

Such a large market opportunity tends to draw heavy competition and the endovascular aneurysm market is no exception. Companies competing in this space include:

• NSVascular (Los Angeles), a subsidiary of NeuroSigma (Los Angeles), which is developing Thin-Film Nitinol (TFN) covered stents for endovascular applications. The company's first two applications of the TFN-covered stents are flow-diverting stents for intracranial aneurysms and stents for treating peripheral artery disease (MDD, July 19, 2011).

• Covidien (Mansfield, Massachusetts), which garnered a pre-market approval from the FDA last year for its Pipeline embolization device. The Pipeline device is designed for large or giant wide-neck brain aneurysms (MDD, April 11, 2011). The company told MDD at the time that it received the PMA for the product that the Pipeline is a new class of embolization device designed to divert blood flow away from the aneurysm in order to provide a complete and durable aneurysm embolization, while maintaining the patency of the parent vessel.

• NeuroVasx (Maple Grove, Minnesota) is also developing a device for the cPAX, for large or giant wide-neck brain aneurysms (MDD, April 7, 2011). cPAX is a polymeric strand delivered into the aneurysm using a technique similar to currently available platinum coil technologies, the company noted. cPAX, because of its soft polymeric material, is designed to achieve more complete filling of the aneurysm with the probable benefit of greater long-term stability, according to NeuroVasx. A significant feature of cPAX in comparison to currently available technologies is that it offers the physician the ability to detach the device at any point versus a fixed detachment zone common in platinum coils. The polymeric material also allows for non-invasive CT and MRI scans with little or no artifact for more accurate patient follow-up assessment.

• Elana Medical (Utrecht, the Netherlands), which has developed a surgical kit, the ELANA (Excimer Laser Assisted Non-Occlusive Anastoamosis), to allow neurosurgeons to reroute blood flow around an aneurysms or a tumor in the brains of patients at greater risk of stroke during standard bypass surgery. The ELANA kit consists of a small platinum ring and a hand piece connected to a surgical laser and suction tubing (MDD, March 14, 2011);

• Codman & Shurtleff (Raynham, Massachusetts) launched the stretch-resistant Xtrasoft Orbit Galaxy Coil, which it claims is the softest endovascular finishing coil for use in the treatment of cerebral aneurysms, about two years ago (MDD, July 28, 2010). Xtrasoft with Truseek Technology features a random loop design. Codman says the coil's shape makes it highly conformable, enabling the device to seek and fill open spaces in cerebral aneurysms for higher packing densities, which have been correlated with low patient retreatment rates. Xtrasoft also features an outer diameter of 0.012 inches, which delivers significantly higher packing volume per cm of length than comparable 0.010-inch systems, the company said. Endovascular coils are inserted directly into the aneurysm through a microcatheter, a small, thin, hollow tube, to seal off the aneurysm, block blood flow and prevent rupture. Finishing coils are small, soft coils used at the final stages of an aneurysm coiling procedure, Codman & Shurtleff noted.