A Randomized, Controlled, Double-blinded, Within-subject (Split-face), Multicenter, Prospective Clinical Study to Compare the Level of Pain Using the Dermal Filler RHA® 4 Formulated With Two Different Anesthetics in the Treatment of Nasolabial Folds

This is a randomized, controlled, double-blinded, within-subject (split-face), multicenter, prospective study to investigate whether RHA® 4 with New Anesthetic Agent is non-inferior to RHA® 4 (with lidocaine) in terms of injection site pain felt by the subject during injection. At screening, the Treating Investigator (TI) evaluated subjects' NLF severity (using the Wrinkle Severity Rating Scale; WSRS) to confirm eligibility and to establish a pre-treatment score for assessing aesthetic improvement. At Visit 1, RHA® 4 With New Anesthetic Agent was administered in a random sequence (first or second injection) and side of the face (left or right) and RHA® 4 with lidocaine was administered to the other side. Study subjects and the TI injecting study devices were blinded. Immediately after injection of each side, subjects rated injection site pain experienced during injection using a 100 mm Visual Analog Scale (VAS). Injection site pain in each side of the face was also assessed at 15, 30, 45 and 60 minutes post-injection. Safety evaluation consisted of AE assessments, a 30-day CTR (Common Treatment Response) diary and a follow-up call performed by the study site at 72 hours after injection. Subjects attended Visit 2 (30 days post-injection) where efficacy and safety assessments will be conducted. Subjects who present with an unresolved clinically significant device related AE at Visit 2 received the optional follow-up phone call no later than 30 days after Visit 2. If the clinically significant AE remained unresolved, the Investigator requested that the subject attended the optional in-clinic follow-up visit (i.e., Visit 3) within 5 working days. Follow-up of the clinically significant AE continued until the AE was resolved or the TI determines that additional follow-up was not necessary.