Comparative Effectiveness of 5-Fluorouracil Dissolving Microneedle Patch vs. 5-Fluorouracil Intralesional Injection for the Treatment of Keloid Scars: A Randomised, Single-Blinded, Split-Scar Study.

Intralesional 5-fluorouracil (5-FU) injections are effective for treating keloid scars but are often associated with pain, hyperpigmentation and ulceration, limiting patient compliance. Dissolving microneedle (DMN) patches offer a novel, minimally invasive and potentially painless alternative for drug delivery. This study aimed to compare the efficacy and safety of 5-FU DMN patches with intralesional 5-FU injections for the treatment of keloid scars. A total of 37 patients were enrolled in this randomised, single-blind clinical trial. Each scar was split in half, with one half treated weekly using 5-FU DMN patches for 12 weeks and the other half receiving monthly intralesional 5-FU injections over the same period. Outcomes were assessed using the Patient and Observer Scar Assessment Scale (POSAS) and scar volume measurements via multispectral imaging at baseline and Weeks 4, 8, 12 and 24. Both treatments significantly improved POSAS scores and reduced keloid volume over time. Intralesional injections resulted in a faster response and significantly greater volume reduction at Week 12 (p = 0.008), but by Week 24, no significant difference in efficacy was observed between the two methods. DMN patches were associated with significantly less pain and better patient comfort. These findings support the use of 5-FU DMN patches as a minimally invasive, patient-friendly alternative to injections for the long-term management of keloid scars.