Elixir Medical has announced that the BIOADAPTOR RCT trial of the company’s DynamX coronary drug-eluting bioadaptor compared to Resolute Onyx (Medtronic) drug-eluting stent met its primary endpoint of target lesion failure (TLF) non-inferiority at 12 months.
The novel bioadaptor scaffold achieved a 1.8% TLF rate compared to 2.8% for Resolute Onyx DES (p<0.001), as well as similar acute performance, acute lumen gain, and percent diameter stenosis at baseline. And, the bioadaptor scaffold demonstrated normal pulsatility in the device treated segment, confirming restoration of vessel function at 12 months. The data were presented at a late-breaking clinical session during EuroPCR 2023 (16–19 May, Paris, France).
DynamX Bioadaptor is a coronary implant designed to to return normal vessel motion and function after percutaneous coronary intervention (PCI), with continued dynamic support of the atherosclerotic vessel to reduce long-term adverse events, Elixir Medical said in a press relese.
In the study, the bioadaptor demonstrated superior effectiveness of its mechanism of action across secondary intravascular imaging endpoints, achieving restoration of the vessel motion and function compared to persistent constraint with DES.
“It is widely believed that caging the vessel by stents has limited the field from overcoming the suboptimal efficacy and safety events,”said Shigeru Saito (Shonan Kamakura General Hospital, Kamakura, Japan) principal investigator in the study. “The DynamX Bioadaptor exceeded our expectations against a good DES in clinical outcomes, and for the first time ever demonstrated restoration of vessel pulsatility, motion and function by uncaging the vessel. These findings establish that the bioadaptor addresses the shortcomings of DES and bioresorbable scaffolds, and collectively point to a technology effectiveness standard not seen before. The finding of plaque changes is very exciting, pointing to a new effect and potential benefit of restoring vessel function.”
The study’s primary endpoint was met, with the DynamX Bioadaptor demonstrated as non-inferior to Resolute Onyx in target lesion failure (TLF) at 12 months (1.8% vs. 2.8%, p <0.001), a 35% difference.
Across components of TLF, there were no cardiac deaths in the DynamX arm, and very low rates of target vessel myocardial infarction, and target lesion revascularisation in both arms.
Results also show that the device restored vessel pulsatility, with lumen area changes during cardiac cycle measured with stationary intravascular ultrasound (IVUS) at multiple sections along the length of the devices and adjacent non-treated vessel segments.
At 12 months, the DynamX in-device lumen area showed ability to significantly increase compared to post-implant and expand by 7.5% between systole and diastole cardiac cycles, at a rate similar to non-treated segments of the vessel, while DES continued to be constrained due to caging.
DynamX was significantly more effective at maintaining an open lumen at 12 months compared to DES with percent diameter stenosis (%DS) at 12.7% vs. 17.3% (p=0.05) and late lumen loss (LLL) being significantly lower at 0.09mm vs. 0.25mm for DynamX and Resolute Onyx, respectively (p=.038). These measures were also lower across key vessel and lesion subsets of LAD, long lesions (≥23mm) and small vessels (≤2.75mm). Similar trend in low LLL was observed across vessel and lesion subsets in patients with diabetes.
In a post-hoc analysis of the 100-patient IVUS cohort, the DynamX arm showed only a 3% change in in-device plaque volume (original lesion plaque treated by PCI) while the DES arm showed a significantly higher 12% increase (p=0.032). Over 90% of the patients in both study arms were on lipid lowering medication for secondary prevention. When lesions were analysed for plaque composition those that had higher content of lipids showed a regression of -9% in plaque volume with DynamX compared to an increase of +10% with DES (p=0.0008), pointing to a hypothesis of a synergistic effect between restoration of vessel motion and function with DynamX and systemic use of lipid-lowering medications.
