Debra L. Beck, MSc
During a late-breaking trials session at AMP 2020 Virtual, Marianne Brodmann, MD, from the Medical University of Graz, Graz, Austria, presented 12-month findings and 3-year safety analyses for the Lutonix BTK IDE study.
The device used was the BD Lutonix 0.14 drug-coated balloon (DCB) and percutaneous transluminal angioplasty (PTA) dilation catheter, eluting paclitaxel compared to PTA alone. The design was a prospective, multicenter, randomized, single-blind design with patients, core laboratory, and clinical events committees all blinded to random allocation.
Most patients (62%) were enrolled in the United States (32 sites), but there were also 14 sites enrolling in Europe and Canada, and 5 sites in Japan. Total enrollment is 442 patients with mainly critical limb ischemia (Rutherford 3-5, but mostly Rutherford 4-5). Mean age was 72.9 years and about 30% female.
As previously reported, the 30-day primary safety endpoint of freedom from major adverse limb events and perioperative death was 99.3% versus 99.4% for DCB versus PTA, respectively (P<0.0001 for noninferiority).
The composite efficacy endpoint of primary patency and limb salvage at six months was 74.7% versus 64.2% for DCB and PTA, respectively (P=0.02, not meeting pre-specified Bayesian P-value for superiority of 0.0085).
“There was a narrowing and catching up in both treatment arms [to 12 months],” said Dr. Brodmann.
“There were also some secondary observations, and I think this is very worthwhile to look deep into this at 12 months — cumulative target lesion interventions remained smaller and lower in the DCB group than in the PTA group [17.8% and 21.8%; P=0.39], but this was not statistically significant anymore,” she reported.
No differences, but a numerically higher toe-brachial index was noted with DCB (0.50 at 12 months vs 0.43; P=NS).
“With regard to wound assessment, only around 30 to 45% of wound photos could be assessed and there was no difference with regard to wounds being present at different treatment times in both groups,” said Dr. Brodmann.
“Because long-term data regarding paclitaxel-coated devices is very important, especially in the CLI group,” Dr. Brodmann reported that freedom from all-cause death, freedom from major amputation, and amputation-free survival were all similar between groups at 3 years. “So, there was no difference with regard to safety in the long term,” said Dr. Brodmann.
In summary, she said, DCB treatment for symptomatic infrapopliteal arterial lesions was non-inferior to PTA alone at 30 days in terms of safety, with a 10.5% numerical difference in the composite primary patency and limb salvage in favor of DCB at 6 months (not significant by binary analysis), and with no difference seen in the composite efficacy endpoint at 12 months, a result tempered by secondary outcomes that appeared to favor DCB. Three-year safety was comparable between groups.
“A first look at 3-year efficacy shows, once again, no statistically significant difference between both groups at three years,” said Dr. Brodmann.