Micell's MiStent Supported by Published DESSOLVE I Results

September 18, 2013—John Ormiston, MD, et al published imaging and clinical results of the DESSOLVE I trial of the MiStent (Micell Technologies, Inc., Durham, NC) in the treatment of patients with de novo lesions in the native coronary arteries. The study is available online ahead of print in the Journal of the American College of Cardiology (JACC): Cardiovascular Interventions. 

The first-in-human, multicenter DESSOLVE I study sought to prospectively examine the safety and efficacy of MiStent, which is a new, cobalt chromium, thin-strut, absorbable, polymer-coated, sirolimus-eluting coronary stent. In the background of the study, the investigators noted that bioabsorbable polymers on drug-eluting stents may lower the long-term risks of inflammation, delayed healing, and adverse events.

As summarized in JACC: Cardiovascular Interventions, the DESSOLVE I investigators enrolled patients with symptomatic coronary artery disease with stable or unstable angina pectoris and > 50% diameter stenosis, amenable to coverage with a ≤ 23-mm-long stent in a vessel 2.5 to 3.5 mm in diameter. All patients received dual-antiplatelet therapy after implantation. Patients underwent repeat angiography, intravascular ultrasound, and optical coherence tomography at 4, 6, or 8 months, and all patients were seen or contacted at 18 months of follow-up.

The investigators reported that the median in-stent late lumen loss (LLL) was 0.03 mm (range, −0.22 to 0.21 mm), 0.1 mm (range, −0.03 to 1.2 mm), and 0.08 mm (range, −0.01 to 0.28 mm) at 4, 6, and 8 months, respectively. At 18 months, the median in-stent LLL was 0.08 mm (range, −0.3 to 0.46 mm).

On optical coherence tomography, the proportion of uncovered stent struts decreased from a median of 7.3% (range, 0.4% to 46.3%) at 4 months to 0% (range, 0% to 3.4%) at 18 months. The percentage of neointimal volume obstruction by intravascular ultrasound increased from a median of 5.3% to 9.1% between 4 and 6 months and remained nearly unchanged thereafter through 18 months of follow-up. The only recorded major adverse cardiac event was a myocardial infarction.

The DESSOLVE I investigators concluded that at 18 months of follow-up, the MiStent was associated with a low and stable in-stent LLL, complete strut coverage, and no stent thrombosis.

On June 12, 2013, Micell Technologies announced that it had received CE Mark approval for its MiStent sirolimus-eluting, absorbable, polymer, coronary stent system and that the company is preparing to make the MiStent device commercially available in Europe and other markets where CE Mark approval can expedite the registration process. At that time, the company advised that the MiStent was not yet available for sale in any market. The MiStent European approval was supported by the DESSOLVE I and DESSOLVE II clinical trials, stated the company in the June press release.