Systemic rapamycin without loading dose for restenosis prevention after coronary bare metal stent implantation

The aim of this study was to assess the role of short oral administration of rapamycin, without loading dose, in the reduction of restenosis rate after bare metal stent implantation.

Previous studies suggest that the administration of oral rapamycin reduces angiographic restenosis after bare metal stent implantation.

This was prospective, open-label study of 80 patients randomized to either oral rapamycin (2 mg/day for 30 days, starting within 24 hr of stent implantation) or no therapy after implantation of a coronary bare metal stent. The primary study end point was incidence of angiographic binary restenosis and late loss at six months. The secondary end points were target lesion revascularization (TLR), target vessel revascularization (TVR), and incidence of major adverse cardiovascular events (MACE) at 6 months.

Angiographic follow up was completed in 72/80 (90%) of patients. In the rapamycin group, the drug was well tolerated (22.5% minor side effects) and was maintained in 100% of patients. At six months, the in-segment binary restenosis was 10.5% in rapamycin group vs. 51.4% in no-therapy group, P < 0.001) and the in-stent binary restenosis was 7.9% in rapamycin group vs. 48.7% in no-therapy group, P < 0.001. The in-segment late loss was also significantly reduced with oral therapy (0.29 + or - 0.39 vs. 0.86 + or - 0.64 mm, respectively, P < 0.001). Similarly, after six months, patients in the oral rapamycin group also showed a significantly lower incidence of TLR and TVR (7% vs. 22.7%, respectively, P = 0.039) and MACE (7% vs. 22.7%, respectively, P = 0.039).

This study showed that the administration of oral rapamycin (2 mg/day, without loading dose) during 30 days after stent implantation significantly reduces angiographic and clinical parameters of restenosis.