12-month controlled study in the United States of the safety and efficacy of a permanent 2.5% polyacrylamide hydrogel soft-tissue filler

Objective To evaluate the safety and efficacy of a 2.5% polyacrylamide hydrogel in the aesthetic enhancement of nasolabial folds. METHODS AND MATERIALS The safety and efficacy of a polyacrylamide hydrogel were compared with those of nonanimal stabilized hyaluronic acid (NASHA) in 315 subjects in a double-blind, randomized, multicenter, noninferiority trial with a 12-month follow-up. The primary efficacy end point was mean change in Wrinkle Assessment Scale (WAS) scores at 6 months. The primary safety end point was rate of serious adverse events (AEs) through 12 months after treatment. RESULTS Polyacrylamide hydrogel was as effective as NASHA, and effectiveness persisted throughout the 12-month follow-up. Treatment-related AEs occurred with equal incidence; most were mild to moderate, transient, and related to injection procedure. One serious AE (infection) was thought to be related to treatment with polyacrylamide hydrogel; it resolved within 5 days after appropriate treatment. CONCLUSION This 2.5% polyacrylamide hydrogel offers promise as a long-lasting soft tissue filler. It is well tolerated, as effective as NASHA in correction of nasolabial folds, and persistent. Longer evaluation is required to evaluate longer-term safety and demonstrate duration of effect beyond 12 months. This study was supported by Contura, Soeborg, Denmark. Joan C. Spivak was paid by the sponsor for her editorial assistance.