Micell Technologies, Inc. received CE (Conformite Europeenne) Mark approval for its MiStent® Sirolimus Eluting Absorbable Polymer Coronary Stent System (MiStent SES®) introducing a thin-strut stent that features elimination of the coating from the stent in 45-60 days and the complete absorption of the polymer coating within 90 days. The MiStent SES is unique in providing local drug delivery both during and after the period of polymer absorption, thereby eliminating long-term polymer exposure, a potential cause of delayed healing and late adverse events.
Micell’s Chief Executive Officer, Arthur J. Benvenuto, commented, “The MiStent SES brings a new paradigm of safety without compromise to efficacy or deliverability. With polymer absorption faster than any other DES currently available, we believe the MiStent SES provides a long-term safety profile of a highly deliverable bare metal stent.”
The MiStent SES approval is supported by in-depth clinical analysis from the DESSOLVE I and DESSOLVE II clinical trials. The DESSOLVE II trial met its primary end point: superiority of MiStent SES in minimizing in-stent late lumen loss (LLL) at nine months as compared to Medtronic’s Endeavor® Sprint DES (p<0.001). The trial was a randomized, multi-center study of 184 patients with documented stable or unstable angina pectoris. At nine months’ follow-up, in-stent LLL was 0.27 mm with a target lesion revascularization rate of 0.9%. The major adverse cardiac events (MACE) rates were 4.3% for MiStent SES and 6.7% for Endeavor. In a sub-group of patients, optical coherence tomography (OCT) and endothelial function testing confirmed good vessel healing with excellent strut coverage and normal endothelial function.
The DESSOLVE I first-in-human study provides additional evidence for the potential clinical advantages of MiStent SES’s unique features, with serial angiographic, intravascular ultrasound (IVUS) and OCT assessment of patients at early (6/8 month) and late (18 month) time points. Data analysis of the groups using matched pairs shows no progression of LLL (0.10 / 0.09 mm and 0.09 mm respectively).
Patrick W. Serruys, MD, PhD, Professor of Interventional Cardiology at the Erasmus University, Rotterdam, The Netherlands, said, “MiStent SES uniquely offers physicians an effective DES that converts to a bare metal stent (BMS) in 45-60 days while still providing drug for suppression of neointimal hyperplasia up to 9 months. The MiStent SES brings us a step closer to the ideal DES, which may provide long-term efficacy while still allowing normal vessel healing.”
The company is preparing for a post-marketing clinical program of 2,000 patients comparing the MiStent SES to the Xience® Everolimus Eluting Coronary Stent System in a randomized design to show non-inferiority of target lesion failure at 12 months and superior performance by the MiStent SES at 24 months with significantly less progression of LLL.
With this CE Mark approval, Micell is preparing to make the MiStent SES commercially available in Europe and other markets where CE Mark approval can expedite the registration process. The MiStent Sirolimus Eluting Absorbable Polymer Coronary Stent System is not currently available for sale in any market.
About the MiStent SES
The MiStent Sirolimus Eluting Absorbable Polymer Coronary Stent System (MiStent SES) is designed to optimize healing in patients with coronary artery disease. MiStent’s rapidly absorbable coating is intended to precisely and consistently control drug elution and limit polymer exposure duration to reduce the safety risks associated with current commercially available drug-eluting stent technologies.
The innovative MiStent SES system includes a proprietary stent coating that contains crystalline drug (sirolimus) and an absorbable polymer. The coating provides controlled and sustained release of therapeutic levels of drug as the polymer softens and disperses from the stent into the adjacent tissue. These properties are intended to enhance safety as compared to conventional permanent polymer DES.
Using an approved drug (sirolimus) and polymer (PLGA), Micell’s patented supercritical fluid technology allows a rigorously controlled drug/polymer coating to be applied to a bare-metal stent. The MiStent SES leverages the benefits of Eurocor’s (CE Marked) Genius® MAGIC Cobalt Chromium Coronary Stent System, a state-of-the-art bare-metal stent, which has demonstrated excellent deliverability, conformability and flexibility.
Results of animal studies have determined that the coating is cleared from the stent in 45 to 60 days leaving a bare metal stent and the polymer is completely absorbed into the surrounding tissue within 90 days to promote long-term patency and compatibility with the artery.
Micell was granted CE (Conformite Europeenne) Mark approval for MiStent SES in June 2013.
About DESSOLVE I and DESSOLVE II Studies
The DESSOLVE I trial, the first clinical assessment of safety and efficacy of the investigational MiStent SES, treated thirty patients with de novo lesions in coronary arteries ranging in diameter from 2.5 to 3.5 mm and amenable to treatment with a maximum 23 mm length stent. Subjects were enrolled across five study centers in New Zealand, Australia and Belgium. Three independent subgroups of 10 patients each were evaluated using angiography, IVUS and OCT at three time points: four, six and eight months. The primary efficacy endpoint was in-stent late lumen loss. Safety was assessed by incidence of MACE and presence of strut coverage with tissue within the treated artery at each time point. William Wijns, M.D., Ph.D., Cardiovascular Center, Aalst, Belgium and John Ormiston, M.B.Ch.B., Mercy Angiography Unit, Auckland, New Zealand are co-principal investigators for this trial.
The DESSOLVE II CE (Conformite Europeenne) Mark trial is a randomized, multi-center study of patients with documented stable or unstable angina pectoris. The primary endpoint is superiority of the MiStent SES in minimizing in-stent late lumen loss at nine months, compared to Medtronic’s Endeavor® Sprint DES, as measured by an independent angiography core laboratory in de novo coronary lesions in vessels ranging in diameter from 2.5 to 3.5 mm and amenable to treatment with a maximum 30 mm length stent. The DESSOLVE II study completed enrollment of 184 patients in July 2011. Data analysis confirms that DESSOLVE II met all study objectives, demonstrated a competitive in-stent late lumen loss, and achieved strong signal of safety.
About Micell Technologies Inc.
Micell Technologies is a biomedical company that is enhancing the performance of medical devices with innovative drug-delivery systems. Its unique surface and polymer modification technologies enable Micell to precisely and consistently control drug elution and polymer exposure duration, creating the potential for a therapeutic solution to coronary artery disease without the long-term safety concerns of currently available drug-eluting stents. Micell is also developing a drug-coated balloon for vascular interventions. Visit us at www.micell.com.