Two-Year Analysis of the Japanese Cohort From the Zilver PTX Randomized Controlled Trial Supports the Validity of Multinational Clinical Trials

PurposeTo report a subgroup analysis comparing safety and effectiveness outcomes in Japanese and non-Japanese patients as part of a prospective, multinational, randomized controlled trial (ClinicalTrials.gov identifier NCT00120406) evaluating a paclitaxel-coated drug-eluting stent (DES) compared to percutaneous transluminal angioplasty (PTA) for treating peripheral artery disease. MethodsPatients were randomly assigned to primary DES or PTA. In the Japanese cohort, 27 patients (21 men; mean age 71.2±9.6 years) were randomized to PTA and 25 patients (19 men; mean age 69.8±10.2 years) to primary DES. In the non-Japanese cohort, 211 patients (131 men; mean age 67.3±10.6 years) were randomized to PTA and 211 patients (136 men; mean age 67.6±9.5 years) to primary DES. Outcome measures included event-free survival (EFS), freedom from target lesion revascularization (TLR), patency, stent fracture, and sustained clinical benefit through 2 years. ResultsSafety and effectiveness outcomes were similar in the Japanese and non-Japanese cohorts, although the outcomes in the Japanese cohort treated with primary DES were numerically better. In the DES group, the 2-year EFS was 92.0% vs. 85.0% (p=0.61), freedom from TLR was 96.0% vs. 85.5% (p=0.55), primary patency was 80.0% vs. 74.3% (p=0.61), and clinical benefit was sustained in 88.5% vs. 80.5% of patients (p=0.31) in the Japanese and non-Japanese cohorts, respectively. Stent fractures were seen in 4 of 457 stents at 12 months: 3 in the Japanese cohort and 1 in the non-Japanese cohort. ConclusionThe subgroup analysis comparing Japanese and non-Japanese patients supports the safety and effectiveness of the paclitaxel-coated DES in Japanese patients with stenotic lesions in the femoropopliteal arteries. The lack of major differences associated with ethnicity in these 2-year outcomes supports the validity and value of multinational clinical trials.