Evolution of microneedle applicators for vaccination: the role of the latch applicator in optimizing dissolving microneedle-based immunization

Expert Opin Drug Deliv. 2024 Dec;21(12):1823-1835. doi: 10.1080/17425247.2024.2422939. Epub 2024 Oct 30.

Abstract

Introduction: Dissolving microneedles (DMN) offer advantages in vaccine delivery, such as enhanced immunogenicity and simplified administration, by targeting immune-rich layers of the skin. However, these benefits require precise and consistent delivery, which poses practical challenges. To address this, specialized applicators are essential for ensuring the accurate deployment of DMNs, making this technology a viable alternative to traditional methods, particularly in low- and middle-income countries (LMICs), where healthcare infrastructure is limited.

Areas covered: In this review, we examine the advancements in DMN-based vaccination and applicator design, focusing on their joint effort. These innovations have improved the precision and efficiency of DMN vaccine delivery. Complex and costly early-stage applicators have evolved into simpler and more cost-effective designs. We highlight these developments in this review, with the latch applicator as a key example of a feature that enhances vaccine delivery.

Expert opinion: Although applicator development has advanced DMN-based vaccination toward practical use, challenges remain. Key areas for further optimization include user friendliness, cost, packaging volume, and wear time. Once optimized, DMN vaccination may become a highly effective and accessible tool for global immunization, supporting efforts to achieve worldwide vaccine equality.

Keywords: Applicator; dissolving microneedle; global vaccine inequity; latch applicator; microneedle; vaccination.

Publication types

  • Review

MeSH terms

  • Administration, Cutaneous
  • Animals
  • Developing Countries
  • Drug Delivery Systems* / instrumentation
  • Equipment Design
  • Humans
  • Microinjections / instrumentation
  • Needles*
  • Vaccination* / methods
  • Vaccines* / administration & dosage

Substances

  • Vaccines