Background: A previous 6-month study using a more highly concentrated novel hyaluronic acid (HA) filler, PP-501-B, found nasolabial fold (NLF) improvements with increased tolerability.

Objective: We investigated the long-term efficacy, durability and safety of PP-501-B in the correction of NLFs.

Methods: Subjects completing the initial six-month study were enrolled in this 24-month, randomized, multicenter, double-blind, split-face, extension study. The injection areas and treatment procedures were identical to those of the initial study: each subject was injected with PP-501-B in one NLF and with Restylane Perlane (Q-med) in the contralateral NLF. We reassessed wrinkle improvement using the five-point Wrinkle Severity Rating Scale (WSRS) and changes in the Global Aesthetic Improvement Scale at 12, 18 and 24 months after the initial treatment.(81名受試者, 有72名完成研究, 以WSRS的指標來評估法令文的改善, 結果高濃度玻尿酸(代號PP-501)與傳統使用的Restylane perlane(瑞絲朗), 皆能有效改善法令紋。於注射後12, 18, 24個月做追蹤, 第一劑注射後, 於半後後再補充, 能使得治療效果延伸長達24個月)

Results: Of the 81 patients enrolled, 72 completed the study. The WSRS score significantly decreased from baseline throughout the follow-up period after retreatment with both fillers. There was no significant difference in the WSRS scores between the two fillers at 24 months. Both fillers were well tolerated with no severe complications or adverse reactions.(受測的兩種玻尿酸皆能有效改善法令紋, 兩者之間並無明顯差異, 且皆未發生嚴重併發症)

Conclusion: The new HA filler PP-501-B is safe and effective in the long term for the correction of moderate-to-severe NLFs, even after a second treatment.