A bioresorbable polymer stent developed in the United States is reporting an important benchmark.
Reva Medical (San Diego, CA) says it has completed a clinical study of its ReZolve drug-eluting bioresorbable scaffold among 26 patients who reported no major adverse coronary events to date. The first patient in the study was enrolled in December 2011.
Principal Investigator Dr. Alexandre Abizaid of the Dante Pazzanese Instituto de Cardiologie in Sao Paulo,
Brazil said: "We are very pleased to have implanted the current ReZolve scaffold in patients with no reported major adverse coronary events to date, and are eager to resume clinical trials with the ReZolve2 scaffold later this year."
REVA plans to provide an update on data from these patients at the Transcatheter Cardiovascular Therapeutics (TCT) 2012 Conference, which will be held in October in Miami, FL.
Patient trials will continued in up to 25 clinical study sites in Brazil, Europe, Australia and New Zealand.
The ReZolve2 scaffold combines a proprietary stent design with a proprietary polymer that is metabolized and cleared from the body. Benefits include full x-ray visibility, clinically relevant sizing and a controlled resorption rate.
Reva Medical, formed in 1998, believes that bioresorbable stents will be the next major advance in coronary stent technology due to risks associated with commercially available metal stents. The global stent market was $4.9 billion last year.
The clinical trials, if successful, will lead to commercialization, first in Europe, then Australia, and then the United States.
The first bioresorbable stent was developed by researchers at Duke University in the early 1980s. There have been many technical challenges to their commercialization, and to date, no coronary bioresorbable stents are available for sale in Europe or the United States. Bioresorbable stents from other manufacturers are expected to become commercial in Europe this year. Earliest possible commercial entry for the Reva bioresorbable stent is believed to be the end of 2014.
Reva uses a "slide & lock" design in which the scaffold is expanded with minimal deformation of the polymer. Polymer stents alone do not have the strength of metal and often break, recoil to a smaller diameter, or collapse entirely. Reva believes its spiral design offers enough radial strength to overcome these issues while minimizing bulk.
Reva says its proprietary polymer "is also less prone to breaking than other polymers that have been tested for this application, and we believe the strength is maintained during the critical 90-day healing period following implant." The Reva polymer is an iodinated, tyrosine-derived polycarbonate.
Reva adds in its 10-K statement to the Securities and Exchange Commission: "We believe our ability to customize our polymer formulation will allow us to create products for additional applications. For example, we believe our polymer and stent technology could be developed for use in peripheral arteries of the leg where stents are prone to crushing and fracturing."
Reva uses a polymer technology originally developed at Rutgers University and still works with researchers at Rutgers to improve the technology. A two-year-old license agreement with Rutgers expands Reva's exclusive rights to the original polymer family and all new polymer compositions developed from this family to cover all vascular applications. Rutgers is expected to receive royalties of $70 to $100 per scaffold sold once the product becomes commercial, in addition to other payments. The Rutgers License requires annual licensing payments of $175,000 until the underlying technology has been commercialized
Polymer manufacturing is currently outsourced to an unidentified American supplier. The catheter and sheath system are purchased from a foreign supplier.
The ReZolve scaffold with its sheath can be implanted using a standard balloon catheter.
Boston Scientific Corp., a major player in stents, was once an investor in Reva and now has an option to negotiate for a worldwide exclusive right to distribute its stent products. Another major medical device manufacturer, Medtronic, is still an investor in Reva.
As of the end of last year, Reva's accumulated deficit was approximately $150 million.