A Multicenter, Randomized, Double-Blinded, Comparative Study of Two Hyaluronic Acid Filler Products for the Correction of Nasolabial Folds

Background: Injecting hyaluronic acid (HA) filler has become the most frequently performed minimally invasive procedure for the correction of the nasolabial fold (NLF). Understanding the property of a specific filler product is important when using HA fillers for NLFs since they differ among individuals in shape and dynamics. Objectives: To compare the efficacy and safety of two commercial HA filler products for the correction of NLFs Patients/Methods: This is a randomized, multicenter, double-blind, split-face study involving 21 Korean subjects with varying degrees of NLFs. Subjects were randomized to assign the injection with a 24 mg/mL monophasic HA gel (YS24) and a 20 mg/mL biphasic HA gel (RP20) to each NLF. Blinded independent evaluators assessed the wrinkle severity rating scale (WSRS) at 3, 12, and 24 weeks after injection. Subjects and treating investigators assessed the global aesthetic improvement scale (GAIS) at 3, 12, and 24 weeks. Any adverse events were assessed during the entire study period. Results: The baseline WSRS scores were 3.29 ± 0.56 for both NLFs. At week 24, the mean WSRS score in YS24- and RP20-treated side were 2.29 ± 0.64 and 2.33 ± 0.66, respectively. There was no statistically significant different change between YS24- and RP20-treated sides. At week 24, the mean GAIS scores of YS24- and RP20-side were 2.10 ± 0.77 and 1.57 ± 0.81, respectively. Adverse events related to the local injection site were temporary and self-limited. No serious adverse effects were observed during the entire follow-up period. Conclusion: Both HA filler products were found to be safe and effective for the correction of NLFs. The results of this spilt-face designed study confirm that YS24 is non-inferior to RP20 in correcting moderate to severe NLFs of Korean subjects. scores ≥ in the evaluating and treating WSRS scores week The five-point scale of WSRS represents severity: “none” (1 point), “mild” (2), “moderate” (3), “severe” (4), “extreme” (5). GAIS scores measure the on a five-point scale: “worsened” (-1 point), “no change” (0), “improved” (1), “much improved” (2), much improved” (3). The pretreatment photograph of each participant served as the reference image at each follow-up visit.