Effects of highly concentrated hyaluronic acid filler on nasolabial fold correction: A 24-month extension study.

[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.

[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.

[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.