Aims: The one year clinical benefit of various doses and release durations of paclitaxel eluted from an erodable polymer has not been evaluated so far.
Methods and results: Conor paclitaxel-eluting stents have intra-stent wells in which drug and polymer are deposited. Stents with six different release formulations (dose: 10 microg or 30 microg, duration: 5, 10 or 30 days, direction: mural or bidirectional) were implanted in 6 patient cohorts. Clinical follow-up was conducted at 4 and 12 months. Quantitative angiography and IVUS were performed at 4 months, and additional angiographic and IVUS follow-up were performed for groups D5 (10microg/30days/mural) and D6 (30microg/30days/mural), as they had shown the most favorable results at 4 months. At one year, the lowest major adverse cardiac event rates were observed in the slow release (30 day) group (5.1% in D5 and 6.9% in D6). One-year in-stent late loss was 0.52+/-0.34 mm in D5 and 0.36+/-0.50mm in D6 (p=0.20) while neointimal area was 0.99+/-0.54 mm2 in D5 and 0.77+/-0.92 mm2 in D6 (p=0.42). Corresponding in-stent binary restenosis at one year was 0% and 5.6% respectively (p=0.36).
Conclusions: Patients who received the slow release formulation stent had better clinical outcome at one year than those who received the fast release formulation. However, the effect on neointimal suppression requires investigation in a larger population to determine whether the high dose formulation confers an additional clinical benefit.