Enhanced Efficacy and Safety of Intra-Tissue Optical Fiber-Guided 5-Aminolevulinic Acid Photodynamic Therapy for Inflammatory Skin Diseases: Preclinical and Clinical Evidence

Traditional ALA-PDT for inflammatory skin diseases causes systemic adverse effects due to non-targeted light exposure. This study evaluates intra-tissue optical fiber-guided ALA-PDT (OFI-ALA-PDT) to enhance precision and safety. Preclinical rabbit ear acne models (n=25) and clinical trials (moderate-severe acne: n=60; nodulocystic acne: n=40; rosacea: n=15) were conducted. OFI-ALA-PDT utilized 3.6% ALA with red light (633±3 nm) delivered via optical fiber needles (3–4 mm depth). Controls received traditional PDT. Animal models showed faster lesion resolution (Day 14: 100% vs. 60% efficacy, P<0.05) and 70% fewer adverse events (20% vs. 90% erythema, P<0.01). Clinically, OFI-ALA-PDT achieved 90% efficacy in moderate-severe acne after 4 sessions (vs. 66.7% controls, χ²=4.812, P<0.05) with 63% fewer adverse events (182 vs. 497 events, P<0.01), 95% efficacy in nodulocystic acne (vs. 55% controls, P<0.05), and 86.7% efficacy in rosacea. OFI-ALA-PDT offers rapid, precise therapy with superior safety, supported by preclinical/clinical data.