In Vivo Reflectance Confocal Microscopy Evaluation of Microneedle Patch Penetration Depth.

BACKGROUND: Firstly, confirm penetration of the skin's most exclusive layer, the stratum corneum (SC), by commercially available microneedle patches using reflectance confocal microscopy (RCM). Secondly, determine the deepest layer of the skin penetrated by the microneedle patches. MATERIALS AND METHODS: In this proof-of-concept study, 3 commercially available dissolving microneedle patches with different active ingredients were included in this study. RCM images of the cheek were taken prior to patch application at 4 different layers of the skin: stratum corneum, stratum spinosum-granulosum, dermal-epidermal junction, and papillary dermis. Patches were then applied to the cheeks of participants according to manufacturer guidelines. Immediately after removal, the same area and layers were imaged using RCM and assessed for features of penetration. RESULTS: Micropores were visualized in RCM images of skin layers post-application of all patches when compared with imaging before application. Characteristics of penetration included uniformly sized, shaped, and spaced well-defined circular areas, which are the created micropores. All 3 patches penetrated the SC to the level of the papillary dermis. CONCLUSION: This study confirms that the dissolving microneedle patches penetrate the most exclusive layer of the skin, the SC, down to the level of the papillary dermis as visualized through RCM. Confirming penetration with RCM shows the potential of these patches to be used for medication transmission. While future studies are needed to assess the efficacy of microneedle patches applied for their advertised skin conditions, confirming the penetration of the microneedle technology through RCM is a significant first step in this process. J Drugs Dermatol. 2023;22(11):1107-1110     doi:10.36849/JDD.6994.

Topical Application of 0.5% Timolol Maleate Hydrogel for the Treatment of Superficial Infantile Hemangiomas.

BACKGROUND: Oral propranolol is considered the first line therapy in the treatment of infantile hemangiomas (IHs). However, there are considerable side effects due to its ability to penetrate the blood brain barrier. Alternatively, topical timolol, a non-selective beta blocker, has resulted in fewer side effects and is 4–10 times more potent in comparison to oral propranolol. This study evaluates the efficacy of 0.5% timolol maleate hydrogel for the treatment of IH. METHODS: This study was conducted via a quasi-experimental design from October 30, 2020 – April 29, 2021, at the Department of Dermatology Benazir Bhutto Hospital, Rawalpindi. 145 infants between 1–12 months in age diagnosed with superficial cutaneous hemangiomas were included in the study with a male to female ratio of 2.4:1. A thin layer of timolol maleate 0.5% hydrogel was applied to the entire surface of the patient’s IH three times daily. Digital photographs and measurements of the hemangiomas were taken at one-month intervals for a maximum of 6 months. RESULTS: The age range in this study was from 1–12 months with a mean age of 6.10 ± 2.52 months. The majority of the patients 89 (61.4%) were between 1–6 months of age. Of the 145 patients, 89 (61.4%) showed an excellent response, 44 (30.3%) showed a good response, and 12 (8.3%) showed no response to the topical 0.5% timolol maleate hydrogel treatment. CONCLUSION: The use of topical 0.5% timolol maleate hydrogel is a promising therapeutic option for the treatment of superficial IHs. Anwar F, Mahmood E, Sharif S, et al. Topical application of 0.5% timolol maleate hydrogel for the treatment of superficial infantile hemangiomas. J Drugs Dermatol. 2023;22(6):594-598. doi:10.36849/JDD.7054.