Final Patient Enrolled In International Trial of MicroVention, Inc.'s HydroCoil(R) Embolic System

ALISO VIEJO, Calif., April 5 /PRNewswire/ -- MicroVention, Inc., a leading developer, manufacturer and marketer of minimally invasive treatments for cerebral and peripheral vascular diseases, announced today that the 500th and final patient has been enrolled in the independent, physician-designed and -managed, international trial of its HydroCoil(R) Embolization System (HES) for treating cerebral aneurysms. Cerebral aneurysms are potentially deadly bulges or sacs in the wall of an artery in the brain.

The head-to-head prospective, blinded, randomized trial, titled HydroCoil Endovascular Aneurysm Occlusion and Packing Study (HELPS), compares the results derived from the HydroCoil system to results from approved bare platinum coils, currently considered the mainstay of endovascular aneurysm therapy. The trial is based in the United Kingdom where it is managed by the Lothian Health Board with initial support from the UK's National Health Service, but a total of 24 medical centers from Scotland, England, Wales, Germany, France, Australia, Brazil, Northern Ireland, Argentina and the U.S. are participating.

Philip White, M.D., of Western General Hospital in Edinburgh, Scotland, the study's chief investigator, will present unblinded safety data and initial angiographic procedural data at the World Federation of Interventional and Therapeutic Neuroradiology meeting (WFITN) in Beijing in September.

"The high level of interest in this trial among the physician community and enthusiasm for obtaining proper scientific evidence allowed us to enroll 500 patients relatively quickly," Dr. White said. "I'm certain that the interest was increased by the fact that the trial was designed and run by physicians who understand the importance of the work we are doing, and the potential of the innovative HydroCoil system that MicroVention has developed to treat cerebral aneurysms. These physicians regularly treat patients who have suffered cerebral aneurysms and realize the potential severity of cerebral aneurysms and the challenges they present. I am very grateful to all our collaborators for their enthusiasm and support and most of all to the 500 patients who have consented to participate in HELPS for the benefit of future aneurysm sufferers. I look forward to sharing the progress we have made in Beijing in September."

Mike Kleine, President and CEO of MicroVention, said the HycroCoil technology, which is a microporous expandable hydrogel, will prove to be a more durable solution for endovascular occlusion of aneurysms. HydroCoil combines the features of greater space filling, cellular organization and mechanical stability with the delivery and handling characteristics of a detachable platinum coil.

"Our goal for this trial is to demonstrate the value of our HydroCoil system to the physician who will be using it in a clinical setting," Kleine said. "Ultimately we believe our HydroCoil system will become the gold standard for treating cerebral aneurysms. We applaud the independent scientific approach that was undertaken by the physicians in HELPS. Unlike other endovascular coil studies, the HELPS trial allowed platinum coils from all manufacturers to be used, and had a primary endpoint of aneurysm recurrence at 18 months versus 6 months in other studies. We feel these HELPS Trial endpoints reduce bias, compare a standard of care more reflective of current practice and allow for a longer and more definitive assessment of the technology's durability. This further demonstrates our belief that HydroCoil will prove to be a superior treatment option.

"The HELPS trial enrollment completion represents a significant milestone in the treatment of cerebral vascular disease," Kleine added. "When evaluating this data along with the many other published and presented data on HydroCoil, we trust the outcomes will further demonstrate the consistency already achieved in these studies -- a significant improvement in recurrence and retreatment rates."

About the HES Procedure

The HydroCoil Embolic System is a unique endovascular embolization device combining the Company's platinum microcoil technology with a proprietary, highly-expandable microporous hydrogel called Intelligel. The Intelligel polymer is a responsive or "smart biomaterial" that does not swell until a period of contact with blood. This responsiveness gives physicians the ability to precisely control delivery of the device and allows for repositioning if necessary. When the hydrogel swells, it provides improved filling of the aneurysm. HydroCoil combines the safety and ease of use of platinum coils with the filling and mechanical stability properties of the hydrogel. HydroCoil offers a new therapeutic alternative to the current treatment choices of platinum coil embolization and neurosurgical clipping, and is also being used clinically to treat fistula and peripheral vascular aneurysms.

About MicroVention, Inc.

MicroVention, Inc. (www.microvention.com) is a company dedicated to the development and commercialization of new catheter-based technologies for the endovascular treatment of peripheral and cerebral vascular diseases. The company has received 510(k) clearance and CE Mark for both its HydroCoil Embolic System and the MicroPlex(R) Coil System to treat cerebral aneurysms and other vascular lesions. MicroVention sells its products through its direct sales force in the U.S., Canada, France, Germany and the United Kingdom and through distributors in numerous other countries. In March 2006, the Company merged with Tokyo-based Terumo Corporation, an international manufacturer and provider of general hospital, cardiac, vascular and home healthcare products.

MicroVention Contacts: Michael Kleine, President, CEO Matt Clawson (Media) William Hughes, Vice President, CFO Allen & Caron, Inc. Ph. 949-461-3314 Ph. 949-474-4300 Fx. 949-461-3329 Fx. 949-474-4330

CONTACT: Michael Kleine, President, CEO, or William Hughes, VicePresident, CFO, both of MicroVention, Inc., +1-949-461-3314, fax+1-949-461-3329; or Media, Matt Clawson of Allen & Caron, Inc.,+1-949-474-4300, fax +1-949-474-4330, for MicroVention, Inc.

Web site: http://www.microvention.com/