Transdermal Delivery of Sumatriptan Succinate Using Iontophoresis and Dissolving Microneedles

This study focuses on the in vitro transdermal transport of sumatriptan succinate using combined iontophoresis and dissolving polymeric microneedle arrays. Permeation experiments were performed to evaluate the effects of formulation parameters on drug release from polyvinylpyrrolidone systems under mild electrical current (<= 500 mu A/cm(2)). The preparations consisted of hydrophilic, positively charged molecules encapsulated in a water-soluble and biocompatible polymeric material. Current densities of 100, 300, and 500 mu A/cm(2) were applied during a 6-h period using silver/silver chloride electrodes. The circular array consisted of 600 needles and occupied a 0.785 cm(2) area. Tests, carried out with Franz diffusion cells and skin of Gottingen minipigs, showed that small decreases in the polymer concentration led to negligible lag times and marked increases in the cumulative amount of drug permeated in 6 h (Q(6h)) and in the flux (J(ss)). At 500 mu A/cm(2), Q(6h) and J(ss) nearly doubled for a microneedle loaded with 5% (w/w) sumatriptan and 20% (w/w) PVP (lag time = 0 min; Q(6h) = 2888 mu g/cm(2); J(ss) = 490 mu g/cm(2)/h) relative to a system loaded with 5% (w/w) drug and 30% (w/w) PVP (lag time = 36 min; Q(6h) = 1437 mu g/cm(2); J(ss) = 266 mu g/cm(2)/h). (c) 2019 American Pharmacists Association (R). Published by Elsevier Inc. All rights reserved.