Microneedles for drug delivery: recent advances in materials and geometry for preclinical and clinical studies

ABSTRACT

Introduction

A microneedle array patch (MAP) has been studied as a means for delivering drugs or vaccines and has shown superior delivery efficiency compared to the conventional transdermal drug delivery system (TDD). This paper reviews recent advancements in the development of MAPs, with a focus on their size, shapes, and materials in preclinical and clinical studies for pharmaceutics.

Area covered

We classified MAPs for drug delivery into four types: coated, dissolving, separable, and swellable. We covered their recent developments in materials and geometry in preclinical and clinical studies.

Expert opinion

The design of MAPs needs to be determined based on what properties would be effective for the target diseases and purposes. In addition, in preclinical studies, it is necessary to consider not only the novelty of the formulations but also the feasibility of clinical application. Currently, clinical studies of microneedles loaded with various drugs and vaccines are in progress. When the regulation of pharmaceutical microneedles is established and more clinical studies are published, more drugs will be developed as microneedle products and clinical research will proceed. With these considerations, the microneedle array patch will be a better option for drug delivery.

KEYWORDS:

• Microneedles
• geometry
• pharmaceutics
• materials
• preclinical studies
• clinical studies

Article highlights

• A microneedle array patch (MAP) is a novel transdermal drug delivery system that can deliver a wide range of therapeutics with superior efficiency compared to conventional transdermal drug delivery (TDD).

• There are four types of MAPs based on their delivery method: coated MAP, dissolving MAP, separable MAP, and swellable MAP.

• Stimuli-responsive MAPs provide controlled drug release in response to specific stimuli or conditions. As a result, they can achieve feedback control or on-demand delivery.

• Many preclinical studies have suggested that the effectiveness of MAP drug delivery depends on the materials, size, and shape of the MAP.

• The effectiveness of MAPs has been demonstrated in several clinical trials, but the cases are far less than preclinical studies.

Acknowledgments

This work was funded by grants from Korea Ministry of Trade, Industry & Energy (MOTIE, 10067809 (Industrial Strategic Technology Development Program)). We appreciate Quadmedicine for providing information of status of clinical studies of microneedles.

Declaration of interest

PJH is an inventor of patents that have been licensed to companies developing microneedle-based products, is a shareholder of companies developing microneedle-based products.