Cutaneous iontophoretic delivery of CGP69669A, a sialyl Lewis(x) mimetic, in vitro.

The aim was to investigate the feasibility of using iontophoresis for the cutaneous delivery of the E-selectin antagonist CGP69669A, a sialyl Lewis(x) -glycomimetic with potential activity against inflammatory skin diseases. The effects of current density and formulation on iontophoretic transport were evaluated in porcine and human skin in vitro. Cumulative permeation of CGP69669A increased with current density (69.73±9.51, 113.97±26.80 and 160.44±13.79μg/cm(2) at 0.1, 0.3 and 0.5mA/cm(2) , respectively) and drug concentration (37.42±13.13, 78.96±23.13 and 160.44±13.79μg/cm(2) , at 1, 3 and 5mg/ml, respectively). In contrast, passive delivery was negligible. Although permeation from a 2% hydroxyethyl cellulose gel was lower than that from aqueous solution, skin deposition - more relevant for the local treatment of dermatological conditions - was 3-fold higher. The results demonstrated that although CGP69669A cannot be delivered passively into the skin it is an excellent candidate for transdermal iontophoresis, a technique that is ideally suited to the delivery of glycomimetics.