Safety evaluation of stamp type digital microneedle devices in hairless mice

A comparative study on a biodegradable hyaluronic acid microneedle patch with a needleless patch for dry skin in atopic dermatitis: a single-blinded, split-body, randomized controlled trial

To overcome interruption of skin barrier in transdermal drug delivery, the microneedle (MN) patch penetrates the barrier by punching with its MNs. Setting a needleless patch (NL patch) as the control intervention, this study assessed the efficacy of a biodegradable hyaluronic acid MN patch (BHMN patch) for atopic dermatitis (AD) patients with dry skin. Similar two AD lesions were selected from the extremities of a participant. For one lesion, a BHMN patch was attached for 6-8 h on where an aroma cream was applied (BHMN patch group). Simultaneously, an NL patch was attached on the other lesion as in the BHMN patch group (NL patch group). For 2 weeks, the interventions were conducted 3 times a week. The local scoring AD (L-SCORAD) index, the visual analog scale for pruritus and skin dryness, skin hydration, the transepidermal water loss (TEWL), and safety were assessed. Fifteen participants finished this trial with no dropouts. Both groups improved the L-SCORAD index after 2 weeks (p < 0.05), but the score of the BHMN patch group decreased more than that of the NL patch group (p < 0.05). The other outcomes, except for the TEWL, also showed statistical significance in intragroup comparisons. Nevertheless, none of the other outcomes showed statistical significance in intergroup comparisons. The TEWL showed no statistical significance even in intragroup comparison. Recoverable minor adverse events were reported in three cases. Considering the result of L-SCORAD index, the BHMN patch may be effective for ameliorating AD. However, a large-scale confirmatory trial is necessary to reassess other outcomes.Trial Registration: This study was registered with the Clinical Research Information Service, Republic of Korea (Submitted date: 04/01/2022, Registered date: 23/02/2022, The first participant enrollment: 01/12/2021, Registration No. KCT0007037).

Micromolding of Amphotericin-B-Loaded Methoxyethylene-Maleic Anhydride Copolymer Microneedles

Biocompatible and biodegradable materials have been used for fabricating polymeric microneedles to deliver therapeutic drug molecules through the skin. Microneedles have advantages over other drug delivery methods, such as low manufacturing cost, controlled drug release, and the reduction or absence of pain. The study examined the delivery of amphotericin B, an antifungal agent, using microneedles that were fabricated using a micromolding technique. The microneedle matrix was made from Gantrez^TM AN-119 BF, a benzene-free methyl vinyl ether/maleic anhydride copolymer. The Gantrez^TM AN-119 BF was mixed with water; after water evaporation, the polymer exhibited sufficient strength for microneedle fabrication. Molds cured at room temperature remained sharp and straight. SEM images showed straight and sharp needle tips; a confocal microscope was used to determine the height and tip diameter for the microneedles. Nanoindentation was used to obtain the hardness and Young’s modulus values of the polymer. Load–displacement testing was used to assess the failure force of the needles under compressive loading. These two mechanical tests confirmed the mechanical properties of the needles. In vitro studies validated the presence of amphotericin B in the needles and the antifungal properties of the needles. Amphotericin B Gantrez^TM microneedles fabricated in this study showed appropriate characteristics for clinical translation in terms of mechanical properties, sharpness, and antifungal properties.

Analysis of Trend of Studies on Microneedle Treatment System (MTS)

Objectives

The purpose of this study was to analyze the microneedle therapy system (MTS) and its research methods for the past 10 years in Korea.

Methods

Data on microneedle therapy system were collected using NDSL, KISS, RISS, and OASIS electronic databases from January 2010 to August 2021. "microneedle," "derma stamp," "microneedle therapy system" were used as the keywords. The present study, however, excluded data that were 1) unrelated to the microneedle therapy system, 2) from review/meta/protocol studies, and 3) from overseas studies. Data selected through the primary screening process, animal studies, case reports, and clinical data were included in the analysis. However, information data not related to the microneedle therapy system were excluded from the study.

Results

Among the MTS-related papers published from January 2010 to August 2021, 7 animal research, 2 clinical trials, and 10 case studies were published. Based on the research topics, there were 8 papers on skin improvement and skin diseases, 7 papers on hair growth and hair loss, 3 papers on stability, and 1 paper on peripheral facial paralysis.

Conclusion

Most of the studies related to MTS focused on skin, hair, and stability. The effect of MTS on hair growth and skin improvement has been confirmed, and it has been proven to have significant effects on the treatment of acne, acne scars, and hair loss in clinical practice. No serious side effects were observed during the MTS treatment, and the safety assessment confirmed that it was safe for use.

Evaluation of efficacy of intradermal injection therapy vs derma roller application for administration of QR678 Neo® hair regrowth formulation for the treatment of Androgenetic Alopecia-A prospective study

BACKGROUND

Non-surgical hair restoration is one of the most exciting and innovative fields in cosmetic surgery today. The addition of latest technique like derma roller seeks to achieve better results for delivering pharmaceutical solution for hair growth in comparison with topical administration.

AIM

We aim to compare intradermal injection vs. derma roller technique for administration of QR678Neo^® hair regrowth therapy for the treatment of androgenetic alopecia (AGA) in male and female patients.

METHOD

A sum of 50 patients in the age range of 20-70 years with AGA were included and divided into 2 groups; Group A (intradermal) and Group B (derma roller). Intradermal injection of QR678Neo^® formulation and derma roller with superficial application of QR678Neo^® was given in each group. Assessment was done using hair pull test, global photographic assessment, video-microscopic assessment, and patient subjective assessment at baseline, 6 months, and 1 year.

RESULTS

Significant diminution in hair fall was seen in both the groups. All the video-microscopic assessment factors were better in intradermal injection group compared to the derma roller group, but not significant. Erythema and pain were high in derma roller group in compare to intradermal.

CONCLUSION

Derma roller technique is more convenient and easy to perform, especially when the availability of a trained person to carry out intradermal injection is not feasible, it gives satisfactory results. It is also beneficial in needle phobic and apprehensive patients. Though the results are more efficacious with intradermal scalp injection technique, this study established satisfactory results with derma roller technique as well.

Current and future technological advances in transdermal gene delivery

Transdermal gene delivery holds significant advantages as it is able to minimize the problems of systemic administration such as enzymatic degradation, systemic toxicity, and poor delivery to target tissues. This technology has the potential to transform the treatment and prevention of a range of diseases. However, the skin poses a great barrier for gene delivery because of the "bricks-and-mortar" structure of the stratum corneum and the tight junctions between keratinocytes in the epidermis. This review systematically summarizes the typical physical and chemical approaches to overcome these barriers and facilitate gene delivery via skin for applications in vaccination, wound healing, skin cancers and skin diseases. Next, the advantages and disadvantages of different approaches are discussed and the insights for future development are provided.

Repeat application of microneedles does not alter skin appearance or barrier function and causes no measurable disturbance of serum biomarkers of infection, inflammation or immunity in mice in vivo

We address, for the first time, the impact of skin insertion on multiple occasions of polymeric microneedle arrays in an animal model in vivo. Dissolving microneedle arrays prepared from aqueous blends of 20% w/w Gantrez® S-97 BF and 40% w/w poly(vinyl pyrrolidone) 58kDa and hydrogel-forming microneedle arrays prepared from aqueous blends of and poly(ethyleneglycol) 10kDa were repeatedly applied to the skin of hairless mice in vivo. Skin appearance and skin barrier function, as illustrated by measurement of transepidermal water loss, were not measurably altered during the entire study period. Biomarkers of infection, immunity and inflammation/irritation were also statistically unchanged, regardless of the microneedle formulation, needle density or number of applications. Mice remained healthy throughout and continued to gain weight during the study. For example, transepidermal water loss values were typically in the range 10-15gm-2h-1 immediately prior to microneedle insertion and 15-25gm-2h-1 immediately following microneedle removal, regardless of when they were measured during the study periods. Serum biomarker levels, measured immediately post-mortem were always in the range 10-20µgml-1 for C-reactive protein, 0.5-1.5mgml-1 for Immunoglobulin G and 1000-2500pgml-1 for interleukin 1-β and were never statistically different from untreated controls. No measurable levels of tumour necrosis factor-α were found in any animals. These findings are encouraging for the formulations investigated, suggesting that their repeated use by patients will not cause undesirable side-effects. By beginning to address potential regulatory questions at an early stage, the microneedles field will be ideally-placed to take advantage of the potential market. This work illustrates a potential pre-clinical strategy for development of regulatory dossiers on microneedle technologies.

Repeated Microneedle Stimulation Induces Enhanced Hair Growth in a Murine Model

Background

Microneedle is a method that creates transdermal microchannels across the stratum corneum barrier layer of skin. No previous study showed a therapeutic effect of microneedle itself on hair growth by wounding.

Objective

The aim of this study is to investigate the effect of repeated microwound formed by microneedle on hair growth and hair growth-related genes in a murine model.

Methods

A disk microneedle roller was applied to each group of mice five times a week for three weeks. First, to identify the optimal length and cycle, microneedles of lengths of 0.15 mm, 0.25 mm, 0.5 mm, and 1 mm and cycles of 3, 6, 10, and 13 cycles were applied. Second, the effect of hair growth and hair-growth-related genes such as Wnt3a, β-catenin, vascular endothelial growth factor (VEGF), and Wnt10b was observed using optimized microneedle. Outcomes were observed using visual inspection, real-time polymerase chain reaction, and immunohistochemistry.

Results

We found that the optimal length and cycle of microneedle treatment on hair growth was 0.25 mm/10 cycles and 0.5 mm/10 cycles. Repeated microneedle stimulation promoted hair growth, and it also induced the enhanced expression of Wnt3a, β-catenin, VEGF, and Wnt10b.

Conclusion

Our study provides evidence that microneedle stimulation can induce hair growth via activation of the Wnt/β-catenin pathway and VEGF. Combined with the drug delivery effect, we believe that microneedle stimulation could lead to new approaches for alopecia.

A potential relationship between skin hydration and stamp-type microneedle intradermal hyaluronic acid injection in middle-aged male face

There is an increasing interest in skin rejuvenation using hyaluronic acid (HA) fillers beyond the improvement of deep wrinkles and volume deficiencies, which have been primary research foci in the past. We conducted a pilot study using a sample of six middle-aged male subjects. Using an automatic intradermal injector with 0.020 mL of material contained in each injection point with a total of 100 points, 2 mL of non-cross-HA filler was injected into the entire face at every treatment session. We administered injections of HA for a total of three sessions per subject at 2-week intervals and evaluated the results using a corneometer, TEWL, cutometer, measures of patient satisfaction, and the global aesthetic improvement scale (GAIS). Corneometer values increased steadily at each measurement, while the average value of TEWL increased in comparison with baseline after each application of the procedure. However, values returned to readings similar to those at 4 weeks after complete termination of the procedures. Cutometer values differed between the baseline and after procedures. All patients were assessed as "very much improved" or "much improved" according to GAIS, and all were pleased with the outcomes of treatment in terms of the enhancement of moisture, elasticity, and brightness.

Microneedles: an innovative platform for gene delivery

The advent of microneedle (MN) technology has provided a revolutionary platform for the delivery of therapeutic agents, particularly in the field of gene therapy. For over 20 years, the area of gene therapy has undergone intense innovation and progression which has seen advancement of the technology from an experimental concept to a widely acknowledged strategy for the treatment and prevention of numerous disease states. However, the true potential of gene therapy has yet to be achieved due to limitations in formulation and delivery technologies beyond parenteral injection of the DNA. Microneedle-mediated delivery provides a unique platform for the delivery of DNA therapeutics clinically. It provides a means to overcome the skin barriers to gene delivery and deposit the DNA directly into the dermal layers, a key site for delivery of therapeutics to treat a wide range of skin and cutaneous diseases. Additionally, the skin is a tissue rich in immune sentinels, an ideal target for the delivery of a DNA vaccine directly to the desired target cell populations. This review details the advancement of MN-mediated DNA delivery from proof-of-concept to the delivery of DNA encoding clinically relevant proteins and antigens and examines the key considerations for the improvement of the technology and progress into a clinically applicable delivery system.

Gene Silencing in Skin After Deposition of Self-Delivery siRNA With a Motorized Microneedle Array Device

Despite the development of potent siRNAs that effectively target genes responsible for skin disorders, translation to the clinic has been hampered by inefficient delivery through the stratum corneum barrier and into the live cells of the epidermis. Although hypodermic needles can be used to transport siRNA through the stratum corneum, this approach is limited by pain caused by the injection and the small volume of tissue that can be accessed by each injection. The use of microneedle arrays is a less painful method for siRNA delivery, but restricted payload capacity limits this approach to highly potent molecules. To address these challenges, a commercially available motorized microneedle array skin delivery device was evaluated. This device combines the positive elements of both hypodermic needles and microneedle array technologies with little or no pain to the patient. Application of fluorescently tagged self-delivery (sd)-siRNA to both human and murine skin resulted in distribution throughout the treated skin. In addition, efficient silencing (78% average reduction) of reporter gene expression was achieved in a transgenic fluorescent reporter mouse skin model. These results indicate that this device effectively delivers functional sd-siRNA with an efficiency that predicts successful clinical translation.