Efficacy and Safety of L‐Carnosine‐Containing Hyaluronate Injection for Facial Skin Hydration and Brightness: A Randomized, Controlled, Evaluator‐Blinded Trial

ABSTRACT Background L‐carnosine, a dipeptide with superior antioxidant and antiglycation properties, serves as the core active component in this study. We aimed to evaluate the efficacy and safety of a novel injectable composite solution, which features L‐carnosine in combination with non‐crosslinked sodium hyaluronate, glycine, alanine, proline, and vitamin B 2 , for improving facial skin dryness and dullness. Methods In this prospective, multicenter, randomized, evaluator‐blinded, superiority clinical trial, 466 subjects were randomized 1:1 to receive either the composite solution injections every 4 weeks for three sessions (treatment group) or no intervention (control group). The control group served as a baseline reference for natural temporal changes. Efficacy was assessed using the Global Aesthetic Improvement Scale (GAIS), the Skin Dryness and Dullness Improvement Scale (SDDIS), the Allergan Fine Lines Scale (AFLS), and the Allergan Skin Roughness Scale (ASRS). A predefined superiority margin of 15% was set for between‐group differences. Blinded evaluators used standardized photographs to score the scales. Safety was evaluated based on adverse events. Results From baseline to Week 12, the treatment group exhibited significantly superior improvements in GAIS, SDDIS, AFLS, and ASRS scores relative to the control group. Efficacy assessed at Week 12 further highlighted this advantage (GAIS: 86.49% vs. 5.26%, SDDIS: 82.88% vs. 5.70%, AFLS: 36.07% vs. 4.57%, ASRS: 47.49% vs. 5.02%; all p < 0.05). These findings were consistent across both full analyses and per‐protocol analyses. Participant satisfaction was significantly higher in the treatment group ( p < 0.05). Treatment‐related adverse events occurred in 94/228 (41.23%) of treated participants, predominantly mild injection‐site reactions (e.g., erythema, swelling) that resolved within 2 weeks. Conclusion This randomized trial demonstrated that the LIVIGI Sodium Hyaluronate Composite Solution for Injection provided favorable clinical efficacy and acceptable safety in improving facial skin dryness and dullness, suggesting its potential as a promising option for skin quality enhancement in aesthetic practice. Furthermore, these findings underscore the growing role of multi‐component synergistic formulations in the evolving field of mesotherapy.