Development and Clinical Study of a Self-Dissolving Microneedle Patch for Transcutaneous Immunization Device

Abstract

These results verified that new-MH is a safe TCI device in human, and greatly encouraged us to advance PI/PII clinical studies of antigen-loaded new-MH.

Microneedle Manufacture: Assessing Hazards and Control Measures

“…There are five principal classes of microneedle used for drug delivery applications: solid, drug coated solid, hollow, dissolvable, and swellable [1][2][3][8][9][10][11][12][13][14][15][16][17][18][19]. The fabrication of solid MN arrays is procedurally the simplest approach and can be constructed from a variety of conventional and inexpensive polymers such as polystyrene, polycarbonate, and polymethylmethacrylate [8][9][10][11][12].…”

“…A typical example of a mould-formed solid (non-dissolvable) polymer MN array cast from a solution of polystyrene is shown in Figure 2 and highlights both the field of needles (A) and the sharp tip that arises (B). Dissolving MN arrays are a relatively new approach and have many advantages over their non-dissolvable analogues [15][16][17]. They can be produced using the same moulds and procedures used for the fabrication of non-dissolvable systems.…”

“…It is only when the needles are subjected to an aqueous environment, particularly alkaline conditions, that the needle swells and their mechanical strength is reduced through gradual dissolution (Figure 3B-D). The dissolvable and swellable systems can be formed from a wide variety of polymer systems with the dissolution rate controlled through the particular formulation employed [15][16][17][18][19]. The scope and intricacies of the latter have been comprehensively reviewed elsewhere [1][2][3] and the compositions exploited in this work are principally used as model systems.…”

“…There are numerous advantages to the adoption of dissolvable or swellable MNs and, in many respects, they represent the least risk in terms of accidental needlestick and the transmission of BBPs. Upon penetration of the skin, they are effectively self-disarming as their piercing capability is generally lost through the process of dissolution or swelling [15][16][17][18][19].…”

Investigation of cell death caused by the Nanopatch™ and its role in vaccine delivery as a physical immune enhancer

“…Complexities of dMN production include designing a suitable geometry, strength and stability, while dissolving upon insertion into the skin. This has led to dMN production of diverse materials such as polymerising monomeric vinyl pyrrolidone using ultraviolet light [283], compressed and dried carboxymethyl cellulose (CMC) [280], a polymer combination of polyvinyl alcohol and polyvinylpyrrolidone [281,319], a combination of CMC with amylopectin and BSA [282,318], hydrogel particles in poly-(lactic-co-glycolic) acid [320], sodium hyaluronate and hydrolysed collagen or sodium hyaluronate, dextran 70 and Povidone [321], polymetamethyl acrylate (PMMA) and other polymers [246,322] etc. Importantly, these materials can influence the dissolution time-frame, thus leading to controlled release over time [282] or fast dissolution upon rehydration [197,[280][281][282].…”