DESolve Nx: Bioresorbable DES Shows Positive Results at 6 Months
PARIS, France—A fully bioresorbable drug-eluting stent (DES) shows low late lumen loss and good safety results at 6 months in patients with de novo coronary lesions, according to findings presented May 21 at EuroPCR 2013.
The DESolve stent (Elixir Medical, Sunnyvale, CA) is a novolimus-eluting device with a scaffold made of PLLA-based polymer that is meant to fully dissolve by 1 year.
For the DESolve Nx trial, researchers led by Alexandre Abizaid, MD, PhD, of the Instituto Dante Pazzanese de Cardiologia (São Paulo, Brazil), used the device to treat 126 patients with single de novo coronary lesions (reference vessel diameter 2.75 mm-3.0 mm; lesion length < 12 mm).
Multimodal Imaging Shows Vessel Restoration
On QCA analysis, minimum lumen diameter (MLD) increased from 0.92 ± 0.40 mm at baseline to 2.67 ± 0.28 mm postprocedure, maintaining at 2.45 ± 0.44 at 6 months. Acute gain was 1.73 ± 0.45 mm postprocedure, while acute recoil was low at 6.6%. Late lumen loss at 6 months, the primary endpoint, was 0.21 mm, which was the same in both diabetics and nondiabetics. In-segment binary restenosis was 3.5% at 6 months. Diameter stenosis decreased from 69.9 ± 12.3% to 13.5 ± 0.8% postprocedure, and maintained at 18.3 v 13.6% at 6 months.
On serial IVUS analysis, mean vessel area increased from 10.44 mm2 postprocedure to 12.23 mm2 at 6 months, an increase of 16.8% (P ≤ 0.001). Mean scaffold area increased over the same time frame from 5.86 mm2 to 6.78 mm2, an increase of 15.7% (P ≤ 0.001), and mean lumen area increased 9.0% from 5.90 mm2 to 6.43 mm2 (P ≤ 0.001). Percent volume obstruction was 5.05 ± 4.20% at 6 months while incomplete scaffold apposition volume was 0.70 ± 0.17 mm3 postprocedure and 0.10 mm3 at 6 months. IVUS showed no late acquired incomplete scaffold apposition and no aneurysm formation.
Meanwhile, on serial OCT analysis, mean scaffold area increased from 7.04 mm2 at postprocedure to 8.17 mm2 at 6 months, an increase of 16.9% (P ≤ 0.001). In addition, frequency of covered struts per patient was extremely high at 98.78 ± 1.69% at 6 months, while mean neointimal hyperplasia thickness was 0.10 ± 0.03 mm. There was no late acquired incomplete scaffold apposition on OCT analysis, with 5 instances at 6 months, down from 15 at baseline.
“This is extremely unique in the bioabsorbable scaffold world,” Dr. Abizaid commented regarding the increased luminal area and scaffold area results. “We could really have vessel restoration within the first 6 months.”
Positive Safety Results
In terms of clinical outcomes, the MACE rate was 3.25% at 6 months, consisting of 1 cardiac death (0.8%), 1 target vessel MI (0.8%) (1 non-Q-wave MI), 2 clinically indicated TLR procedures (both PCI; 1.6%), and no definite stent thrombosis. In the diabetic subpopulation (n = 26), there was only 1 MACE, a non-Q-wave target vessel MI that was attributed to the multimodality imaging procedure.
“The DESolve Nx pivotal trial was successful in demonstrating the safety and efficacy of the DESolve scaffold,” Dr. Abizaid concluded. He noted the device’s high rate of deliverability as well as the low recoil rate and low late lumen loss, percent volume obstruction, neointimal hyperplasia thickness, MACE, and acquired incomplete scaffold apposition, as well as the high rate of strut coverage.
Commenting on the trial, Robert A. Byrne, MB, BCh, PhD, of Deutches Herzzentrum (Munich, Germany), noted that “the significance of these results is that it [hopefully] leads to CE device approval. This will for sure change our practice when we have more bioresorbable scaffolds in the market space. Then we’re going to see further development of this technology in the near future.”
Dr. Byrne asked what, if any, the benefits would be for a bioresorbable scaffold compared with a bioabsorbable polymer stent.
While acknowledging it is probably too early to discuss any clinical advantages, Dr. Abizaid did suggest some potential benefits of the fully bioresorbable technology
“You can see that the degradation really occurs within the first year. Not only the degradation, but the absorption,” Dr. Abizaid said. “The second advantage is the fact that you have a little more freedom to post dilate this scaffold if you need to. To have a device that’s not going to fracture, I think that’s an important advantage.”
Abizaid A. First report on the pivotal DESolve Nx trial: 6-month clinical and multimodality imaging results. Presented at: EuroPCR; May 21, 2013; Paris, France.
- Dr. Abizaid reports receiving research grants from Abbott Vascular, Boston Scientific, Elixir, and Medtronic.