Patient Comfort, Safety, and Effectiveness of Resilient Hyaluronic Acid Fillers Formulated With Different Local Anesthetics

BACKGROUND Maximizing patient comfort during hyaluronic acid gel injection is a common concern that is usually addressed by selecting fillers with lidocaine. OBJECTIVE Two randomized, double-blinded, split-face trials aimed to demonstrate noninferiority of specific hyaluronic acid fillers incorporating mepivacaine (RHA-M) versus their lidocaine controls, at providing pain relief. METHODS Thirty subjects per trial received injections of RHA R -M versus RHA R , and RHA4-M versus RHA4, respectively, in the perioral rhytids (PR) and nasolabial folds (NLF). Pain was assessed on a visual analog scale; aesthetic effectiveness was evaluated with validated scales, and safety was monitored based on common treatment responses (CTRs) and adverse events (AEs). RESULTS RHA-M fillers proved as effective as their lidocaine counterparts at reducing pain (noninferior, p < .0002 and p < .0001). Bilateral wrinkle improvement was measured both in the PR (−1.5 ± 0.6 points on each side) and in the NLF (−1.8 ± 0.6 and −1.9 ± 0.5 points) trials at one month, with virtually identical responder rates (≥96.7%). Common treatment responses and AEs were similar between treated sides, and none was clinically significant. CONCLUSION Resilient hyaluronic acid fillers with either mepivacaine or lidocaine are equally effective at reducing pain during treatment and equally performant and safe for correction of dynamic facial wrinkles and folds.