THUNDER: Restenosis reduced with Paccocath drug-eluting balloons.
Twelve months results for the Local Taxan With SHort Time and Exposure for RedUctioN of Restenoisis in Distal ArtERies (THUNDER) trial, have revealed that Paccocath drug-coated balloons (manufactured by Bavaria Medizin Technologie GmbH) reduce restenosis in the superficial femoral artery. The outcomes were presented by Dr Gunnar Tepe, assistant professor of radiology at the Eberhard- Karls-University of Tuebingen, Germany, and principal investigator of the THUNDER trial. In the trial, 154 patients from three centres were randomised to receive an uncoated balloon (n=54), an uncoated balloon in combination with paclitaxel (n=52), or the paclitaxel-coated angioplasty balloon, called the Paccocath catheter (n=48). Among other inclusion criteria, patients had an occlusion or stenosis of >2cm and a Rutherford score of 3 to 5. All treatment groups were well balanced for patient characteristics. Those in the uncoated balloon arm had an average pre-procedure lesion length of 7.3cm, compared with 6.7cm and 6.5cm for the uncoated balloon-plus-paclitaxel and the Paccocath arms, respectively. Study participants had 1.7 lesions treated on average, and the mean degree of stenosis ranged from 87.7% to 90.7% between the three arms. Previously released six months results revealed that the mean late lumen loss was significantly reduced in the Paccocath arm (P<0.01) when compared with those receiving uncoated balloons. The target lesion revascularisation rate at six months was 29.6% (n=16) in the uncoated balloon arm, 25% (n=13) in the uncoated balloon-plus-paclitaxel arm and 6.3% (n=3) in the Paccocath arm. Binary restenosis at six months in the uncoated balloon arm was identified in 21 patients, in the uncoated balloonplus- paclitaxel arm in 22 patients and in the Paccocath arm in seven patients. Patients in the uncoated balloon arm had mean Rutherford scores of 3.1 at baseline and 1.6 at six-month follow-up, compared with 3.4 and 2.0 in the uncoated balloon-plus-paclitaxel arm and 3.4 and 1.2 in the Paccocath arm, respectively. Twelve month outcomes revealed that the target lesion revascularisation rate, risk of binary restenosis and late lumen loss also remain significantly lower (p<0.01) in those patients treated with the Paccocath compared with the other treatment arms. “The 12-month outcomes gives us evidence that drug-coated balloons reduce restenosis in the superficial femoral artery. The balloon allows the drug is to be delivered in a much shorter period of time and does not leave behind a coated stent, which itself can cause problems. Also, because the coating on the stent remains after the drug has been completely delivered to the vessel wall, it may cause undesired effects later." In a critical commentary, Dr Eric Milnar, University of Vienna, Austria, highlighted that 10-20% of patients were lost to follow-up and said that understanding the long-term risk of restenosis in particularly important. “Restenosis that is caused by neointimal hyperlasia is a slow process, suggesting that the local administration of a drug would need to be prolonged in order to be beneficial. However, the Paccocath technology seems promising and warrants further investigation in larger randomised trials with longer follow-up.”