A comparison of dissolving microneedles and transdermal film with solid microneedles for iloperidone in vivo: a proof of concept

Iloperidone (ILO) is a poorly soluble and bioavailable WHO-approved schizophrenia drug. Microneedles are a revolutionary delivery technology that overcomes many of the issues associated with traditional drug administration. The current research aimed to compare the antipsychotic activity and pharmacokinetics of ILO-loaded dissolving microneedles (DMNs) and transdermal film with a solid microneedle (STF). The DMNs were fabricated using the micromolding process, while the transdermal film was created using the solvent casting approach. Furthermore, an in vivo pharmacokinetic, pharmacodynamic, and skin irritation study was performed on Wistar rats. Studies were compared with transdermal film (TF) on untreated skin as a passive control. STF and DMNs had considerably greater AUC and C-max (p <= 0.001) than transdermal film. In pharmacodynamic tests, STF and DMNs demonstrated significant (p <= 0.001) forelimb retraction time (FRT) and hindlimb retraction time (HRT) delay responses as compared to control and TF. In the skin irritation test, no adverse effects such as erythema or edema were observed at the end of the 48 h. Thus, antipsychotic activity (paw test) and pharmacokinetics studies revealed sustained action of DMN and STF. This research revealed that improved efficacy of DMN and STF for antipsychotic drug delivery may be an alternative to the existing dosage form.