Delayed-Onset Nodules to Differentially Crosslinked Hyaluronic Acids: Comparative Incidence and Risk Assessment

Abstract

Background: Robust and long-term data on true incidence of delayed-onset nodules and immune tolerance of hyaluronic acid (HA) fillers are lacking.

Objective: To characterize the incidence of delayed nodules in Vycross (VYC) HA fillers compared with previously reported FDA and non-FDA data of all HA fillers.

Methods and materials: The incidence of delayed nodules in all patients who had received VYC fillers in a 12-month period was assessed through a retrospective chart review. Nodule incidence for currently approved nonanimal-stabilized hyaluronic acid (NASHA) fillers was assessed using the FDA Summary of Safety and Effectiveness Data.

Results: Overall, 1,029 patients received 1,250 VYC filler treatments. Five patients developed delayed nodules to VOB, with an incidence of 1.0% per patient and 0.8% per syringe. No nodules were observed in patients who received VLR or VOL. All nodules were treated successfully using a combination of intralesional triamcinolone and hyaluronidase. Compared with other currently approved NASHA fillers, VOB is associated with a higher incidence of nodule formation.

Conclusion: The introduction of VYC HAs has introduced a new variable that may be changing the immune tolerance of these substances, resulting in a higher incidence of delayed nodules than previously expected.