Hypertrophic scar (HS) significantly impacts the patients quality of life due to severe itching; hence, most patients focus is on high-quality postoperative rehabilitation. Traditional therapies for HS have many inherent constraints, such as inferior drug delivery efficiency for topical administration and intense pain for intralesional injection. To address this issue, a team of researchers has developed a personalized microneedle patch system for minimally invasive and effective treatment of HS. These microneedle patches are personalized, designed and fabricated using 3D printing to adapt to individual HS. The optimized microneedle patches are made up of dissolving gelatin and starch. They are loaded with losartan, an angiotensin II receptor blocker that can effectively inhibit the proliferation and migration of hypertrophic scar fibroblasts (HSFs) and downregulate the gene expression related to scar formation in HSFs. The dissolving microneedle patches are mechanically strong, effectively penetrate the stratum corneum of HS, and increase losartan delivery into HS upon dissolution of gelatin and starch. 

This system has been shown to effectively inhibit HS formation in rabbit ears, reduce scar elevation index (SEI) and decrease fibrosis and collagen deposition in HS. 

In conclusion, this personalized microneedle patch system offers an efficient drug delivery method with minimal invasion and unlocks new possibilities for personalized management and treatment of skin diseases.

Source: Huang Y, Li J, Wang Y, et al. Intradermal delivery of an angiotensin II receptor blocker using a personalized microneedle patch for treatment of hypertrophic scars. Biomater Sci. 2023;11:583-95.