Background: Nonanimal-stabilized hyaluronic acid (NASHA) fillers are frequently used for facial soft tissue augmentation. Their long-term efficacy and the effects of different retreatment schedules are not well established.
Objective: This is an 18-month interim analysis of a 30-month study to evaluate the efficacy and persistence of NASHA 100,000 gel particles/mL filler with two different retreatment schedules.
Methods: This multicenter, randomized, evaluator-blinded study enrolled 75 patients with moderate to severe nasolabial folds. Patients were randomized to retreatment of one nasolabial fold at 4.5 months and the contralateral fold at 9 months after correction of both folds at the initial visit.
Results: Wrinkle Severity Rating Scale scores improved significantly (p<.001) from baseline, with mean improvements ranging from 1.1 to 1.7 grades. Almost all patients (97%) responded satisfactorily, and the efficacy of the retreatment schedules did not differ significantly. Adverse events, primarily swelling and bruising, occurred in 33% of patients; none were serious.
Conclusion: The improvements seen after initial treatment with NASHA 100,000 gel particles/mL filler persisted for up to 18 months with one retreatment. The response was equivalent for retreatment at 4.5 and 9 months.