Abstract
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.