Nine Month Imaging and Twelve Month Clinical Results from the DESSOLVE II Randomized Trial of the MiStent (R) SES with Absorbable Polymer

Abstract

Background : The MiStent SES (Micell Technologies, Durham, NC) is an investigational drug-eluting stent (DES) developed to adress unfavorable late-term outcomes such as stent thrombosis. These events are hypothesized to be associated in part with durable polymers of current DES. The MiStent SES uses a unique combination of components, a crystalline formulation of sirolimus and a fully absorbable polymer on a thinstrut, cobalt chromium stent platform. The polymer coating is eliminated from the stent in 45-60 days with complete absorption in 90 days. Sirolimus is simultaneously released into the surrounding tissue as a controlled elution. Methods: The DESSOLVE II clinical trial is a 2:1 randomized study conducted at 26 sites evaluating the MiStent SES for superiority in late lumen loss as compared to the control stent, the Medtronic Endeavor Sprint (Santa Rosa, CA). Patients with discrete de novo lesions (2.5-3.5 mm vessel diameter and ≤27 mm length) in native coronary arteries were acceptable for inclusion in the trial. A total of 183 patients were randomized into either the MiStent SES or Endeavour Sprint and patients had follow-up at 30-days, 6, 9 and 12-months post-procedure. Angiography was conducted at 9-months with two subgroups: 38 patients imaged using optical coherence tomography (OCT) and 29 patients participated in endothelial function testing(EFT). Results: The MiStent was superior to Endeavour for the primary endpoint analysis of late lumen loss. The OCT revealed a mean of 2% uncovered struts with good suppression on neointimal hyperplasia. EFT demonstrated an overall return of endothelial function with no incidence of vasoconstriction in either the test or control group. Additional secondary endpoint data will be presented. Conclusion: The MiStent SES is an innovative drug eluting stent with sirolimus in a fully absorbable polymer demonstrating a superior performance as compared to the Endeavor Sprint DES. OCT shows stent coverage at 9-months with a return of endothelial function.