In this study, economic DMN arrays fabricated under mild
micromoulding conditions were shown, for the first time, to be
successful in active transdermal delivery of NC, a model macromo-lecular therapeutic with challenging resistance to passive skin
absorption. The array could be loaded with up to 630 IU of NC
without compromising its mechanical strength or, of vital impor-tance, the drug bioactivity. NC could permeate DHS over a 48-h
study period. Apart from the known benefits of MN technology
in the transdermal delivery of drugs with poor passive skin absorp-tion, DMN arrays intended for simultaneous insertion and drug
delivery proved particularly suitable for LMWH, known to interact
with the skin’sstratum corneum barrier. Direct extrapolation of
data obtained toin vivopermeation of NC across full thickness hu-man skin is, of course, not straightforward. However, DMN patches
offer considerable potential in delivering therapeutic doses of NC.
This could be achieved by modulating drug release and increasing
the area of the MN array patch to meet various in-use clinical
requirements.In vivo animal studies are now planned and will be
aimed at demonstration of the activity of LMWH delivered by
DMN arrays.