Effect of iontophoresis on dacarbazine cutaneous delivery for melanoma topical treatment

Dacarbazine (DTIC) is the drug of choice for melanoma treatment, but its systemic administration is related to several adverse effects. Here, DTIC topical delivery stimulated by iontophoresis is proposed to overcome such drawbacks. Hence, this work analyzed the impact of anodal iontophoresis on DTIC cutaneous delivery to provide an innovative topical alternative for melanoma treatment. The electrical stability of the drug was evaluated prior to the iontophoretic experiments, which demonstrated the need to add an antioxidant to the drug formulation. DTIC cutaneous permeation was evaluated in vitro for 6 h using three current densities (0.10, 0.25, and 0.50 mA/cm²). In addition, the effect of DTIC against skin cancer cells (MeWo and WM164) was investigated for 72 h of exposure to the drug. Iontophoresis stimulated skin drug permeation compared to the passive control. However, the antioxidant presence reduced DTIC permeation under the lower currents of 0.10 and 0.25 mA/cm², which was compensated by increasing the current density to 0.50 mA/cm². At 0.50 mA/cm², iontophoresis enhanced topical cutaneous drug permeation 7-fold (p < 0.05) compared to the passive control. DTIC showed a concentration-dependent antiproliferative effect on melanoma cell lines. Thus, iontophoresis intensifies DTIC skin penetration in concentrations that can reduce cell viability and induce cell death. In conclusion, DTIC cutaneous delivery mediated by iontophoresis is a promising approach for treating melanomas and other skin tumors.