Determination of Rate and Extent of Scopolamine Release from Transderm Scōp® Transdermal Drug Delivery Systems in Healthy Human Adults.

To estimate strength of a scopolamine transdermal delivery system (TDS) in vivo, using residual drug vs. pharmacokinetic analyses with the goal of scientifically supporting a single and robust method for use across the dosage form and ultimately facilitate the development of more consistent and clinically meaningful labeling. A two-arm, open-label, crossover pharmacokinetic study was completed in 26 volunteers.

Effect of dosing regimen and microneedle pretreatment on in vitro skin retention of topically applied beta-blockers.

Topical beta-blocker formulations are commonly used to treat infantile hemangiomas (IHs); however, the skin concentrations and drug permeation through the skin have not been quantified. Microneedles (MNs) may increase local skin concentrations, which could further enhance lesion clearance and improve dosing regimens. The objective of this study was to quantify skin concentrations and drug permeation of two beta-blockers, propranolol and timolol, in vitro after application to intact skin and skin pretreated with solid MNs of two lengths.

In Vitro Skin Retention and Drug Permeation through Intact and Microneedle Pretreated Skin after Application of Propranolol Loaded Microemulsions.

Purpose: Topical beta-blockers are efficacious for treating infantile hemangiomas, but no formulations have been specifically optimized for skin delivery. Our objective was to quantify skin concentrations and drug permeation of propranolol (a nonselective beta-blocker) after application of microemulsions to intact and microneedle pretreated skin.

Methods: Four propranolol-loaded microemulsions were characterized for droplet size, surface charge, conductivity, pH, drug solubility, and drug release.

A Pilot Study to Evaluate the Effects of Topically Applied Cosmetic Creams on Epidermal Responses.

Application of exogenous products, such as creams, to the skin can result in subclinical changes in selected epidermal functions such as transepidermal water loss (TEWL), hydration, redness, and pH; these changes may lead to or contribute to irritation. Changes in skin surface inflammatory factors may provide further insight into this potential for irritation. The objective of this study was to evaluate the changes in epidermal properties and inflammatory mediators after 4 days of topical application of 2 different polymers formulated in cosmetic creams.

Micropore closure kinetics are delayed following microneedle insertion in elderly subjects.

Transdermal delivery is an advantageous method of drug administration, particularly for an elderly population. Microneedles (MNs) allow transdermal delivery of otherwise skin-impermeable drugs by creating transient micropores that bypass the barrier function of the skin. The response of aging skin to MNs has not been explored, and we report for the first time that micropore closure is delayed in elderly subjects in a manner that is dependent upon MN length, number, and occlusion of the micropores.

Optimization of impedance spectroscopy techniques for measuring cutaneous micropore formation after microneedle treatment in an elderly population.

Purpose: The objective of this study was to optimize a reproducible impedance spectroscopy method in elderly subjects as a means to evaluate the effects of microneedles on aging skin.

Methods: Human volunteers were treated with microneedles at six sites on the upper arm. Repeated impedance measurements were taken pre- and post-microneedle insertion.