Benzoporphyrin Derivative Monacid Ring A (Verteporfin) Alone Has No Inhibitory Effect on Intimal Hyperplasia: In Vitro and In Vivo Results

Abstract

ABSTRACT Benzoporphyrin derivative monoacid ring A (Verteporfin, BPD-MA), a photosensitizing drug, has been suggested as having inhibitory effects on smooth muscle cell (SMC) proliferation in rabbit aortic intimal injuries. The effect of BPD-MA on vascular SMCs in the absence of light stimulation in vitro and in vivo was studied using models of intimal hyperplasia. Human SMCs were incubated with BPDMA for 4 h in darkness. A small (20%) but significant decrease in viability (n = 42, p < .05) was noted for BPD-MA concentrations above 15 mu g/mL. This was an all-or-none phenomenon with no further decrease in viability at higher concentrations. Treatment with BPD-MA was also carried out in vivo using a balloon injury model of intimal hyperplasia in rabbit aortas. Thirty-three rabbits were randomized into five groups and given intravenous BPD-MA (2 mg/kg) according to the following schedule: Group 1 (n = 8), BPD-MA 25 min prior to injury; Group 2 (n = 8), BPD-MA 25 min prior to injury plus a second dose 4 weeks later; Group 3 (n = 4), BPD-MA immediately postinjury; Group 4 (n = 7), BPD-MA immediately postinjury plus a second dose 4 weeks later; or Group 5 (n = 6), no drug (control group). No statistically significant difference was seen in the amount of intimal hyperplasia that developed in the five groups.

• Benzoporphyrin Derivative Intimal Hyperplasia Photodynamic Therapy