TCT: LEVANT I trial shows promise for drug-eluting balloons in fem-pop
Moxy, a balloon catheter that delivers paclitaxel to the arterial wall |
According to Scheinert, the MOXY drug-coated balloon has a proprietary paxcitaxel coating and hydrophilic non-polymeric carrier that facilitates the balance and structure during delivery and uptake. The balloon catheter has very short inflation times of almost 30 to 60 seconds, he said.
Patients in both groups were then randomized at a 1:1 ratio to receive either treatment via the MOXY catheter or standard PTA. Of the 75 patients randomized to the balloon group, 37 received treatment via MOXY and 38 via PTA. For the stent group, 12 patients were randomized to receive MOXY and 14 to PTA.
“The primary objective was to assess the safety and efficacy of the MOXY catheter for treatment of stenosis and occlusions in the femoropopliteal artery,” he noted.
The researchers used late lumen loss as the primary endpoint and also looked at rates of target lesion revascularization (TLR), target vessel revascularization (TVR), primary patency and safety.
Scheinert said that operators decided how likely the patients would need a stent in addition to PTA or whether it could be anticipated that the balloon treatment would be appropriate.
Results for the intention-to-treat analysis included a late lumen loss of 0.46 mm for the balloon arm and 1.09 for the PTA arm. For the per-protocol analysis, these numbers were 0.36 mm and 1.08 mm, respectively.
Scheinert noted that these results confirm previous findings from randomized studies.
Secondary endpoints of TLR were 13 percent for the balloon group and 22 percent for the PTA group during the intention-to-treat analysis and 6 percent versus 21 percent, respectively, during the per-protocol analysis.
“For the secondary endpoint of TLR, there was a clear advantage for the balloon-treated arm,” he said. During the protocol analysis, which excluded some patients for major protocol violations including insufficient coverage of the lesion by the drug-eluting balloon, “the difference was even more relevant,” he said.
Additionally, the results showed that patients were on duel-antiplatelet regimens of clopidogrel (Plavix, Bristol-Myers Squibb/Sanofi-Aventis) for shorter periods of time. “In the no-stent group patients received duel-antiplatelet therapy for one month, while the stent group received the medication for three months. There were no reported incidences of acute thrombosis in the MOXY group.”
A sub-analysis of the combination of drug-coated balloon and stents found late lumen loss for both the balloon groups and stent groups to be similar.
“LEVANT I demonstrated a strong biologic effect to inhibit neointimal hyperplasia by using the MOXY drug-coated balloon catheter to achieve the primary endpoint of approved late lumen loss,” he said.
Additionally, he said that these data suggest that the use of the MOXY device is “safe and is associated with a marked decrease in clinical events compared to the control group.”
Scheinert also noted that a shorter duration of antiplatelet therapy seems “feasible and safe” with the use of drug-coated balloons, but said that larger, more pivotal trials may be needed to confirm the results and benefits of treating femoropopliteal arteries with this process.
To further investigate the primary patency and other composite endpoints, researchers will launch the LEVANT II clinical trial.
While Scheinert noted that there were “substantial biological effects” of the primary endpoint, the subgroups of the study were “not powered to show any statistically relevant data. The power calculations were only made for the whole cohort.”
He concluded, “At six months there is, in both groups … a relative reduction of late lumen loss. Of course, patients receiving stents upfront are starting from a somewhat larger minimal luminal diameter after intervention and, therefore, the magnitude of the difference may be somewhat less. Studies would need to be powered independently to investigate the specific effect of balloon with stents. At least from this pilot trial, we are taking the hypothesis that there should be an effect from the presence of drug-coated balloons at least at six months."