Microneedles in Drug Delivery: Progress and Challenges.

In recent years, an innovative transdermal delivery technology has attracted great interest for its ability to distribute therapeutics and cosmeceuticals for several applications, including vaccines, drugs, and biomolecules for skin-related problems. The advantages of microneedle patch technology have been extensively evaluated in the latest literature; hence, the academic publications in this area are rising exponentially. Like all new technologies, the microneedle patch application has great potential but is not without limitations. In this review, we will discuss the possible limitations by highlighting the areas where a great deal of improvements are required. Emphasising these concerns early on should help scientists and technologists to address the matters in a timely fashion and to use their resources wisely.

Clinical efficacy of dissolvable microneedles armed with anti-melanogenic compounds to counter hyperpigmentation.

BACKGROUND: Hyperpigmentation is a complex physiological process associated with alterations of skin color due to melanin overproduction and distribution. Both intrinsic and extrinsic factors influence discoloration with the involvement of multiple pathways in cooperative manners. Restoring natural skin color requires a multi-targeted approach. Latest advances in anti-melanogenic compounds and microneedle delivery system have presented opportunities for tackling hyperpigmentationsuccessfully. AIMS: This work was aimed at assessing the dermal tolerability and efficacy of hyaluronic acid-based microneedle patches loaded with anti-melanogenic actives for improvements of skin discoloration. PATIENTS/METHODS: The test products consist of hyaluronic acid with niacinamide, ascorbic acid 2-glucoside, tranexamic acid, resveratrol, 4-n-butyl-resorcinol, and Halidrys siliquosa extract. In a monocentric 12 weeks clinical trial, the HA-MNs patches were applied to the affected areas of the faces on subjects with hyperpigmented skin. The color properties of the skin were analyzed spectrophotometrically. RESULTS: The products were tolerated remarkably; none of the subjects informed any primary or cumulative skin responses. Evaluation of color related measurable skin properties provided insight into the general effectiveness: The individual topology measurements showed 51.4% noticeable improvements in hyperpigmented zones, which were also in good agreement with the personal impressions of the subjects determined by questionnaires before and after the treatments. CONCLUSIONS: The concentrated blends of actives in microneedle patches act in a multi-targeted manner, and they could be worked in a complementary fashion for the improvement of skin color and appearance. The study has established the overall convenience of the HA-MNs with the formulation of anti-melogenic compounds against skin discoloration.

Efficacy of bioactive peptides loaded on hyaluronic acid microneedle patches: A monocentric clinical study.

BACKGROUND: Aging skin is a gradual physiological process associated with functional and structural changes of the skin. Both intrinsic and extrinsic factors influence skin aging by the involvement of multiple pathways. Restoring natural skin conditions requires a multi-targeted approach. Recent developments in both bioactive peptides and microneedle delivery system have presented an opportunity for tackling premature skin aging. AIMS: This study was aimed at evaluating the dermal tolerability and efficacy of hyaluronic acid-based microneedle patches loaded with bioactives for restoration of the skin properties including hydration, wrinkle reduction, density, and thickness. PATIENTS/METHODS: The test product of HA-MNs comprises arginine/lysine polypeptide, acetyl octapeptide-3, palmitoyl tripeptide-5, adenosine, and seaweed extracts. In the monocentric 12-week clinical trial, the HA-MNs patches were applied to the outer corner of the right and left eye and a defined area on the volar forearm on healthy subjects with aged skin. Instrumental analysis of skin properties was determined. RESULTS: The product was tolerated excellently; none of the subjects reported any primary or cumulative skin reactions. Assessment of measurable skin properties provides insight into the general effectiveness: The fine lines/wrinkles showed 25.8% noticeable decrease; the skin hydration measurements demonstrated 15.4% improvement; the skin density and thickness in the dermis increased 14.2% and 12.9%, respectively. CONCLUSIONS: The composition of the microneedle patches works in a multi-targeted manner and all ingredients might possibly be acted synergistically for the improvement of skin structure, function, and appearance. The study has demonstrated the overall usefulness of the HA-MNs with careful formulation for skin care applications.