Efficacy and Safety of Polycaprolactone in Treating Nasolabial Folds: A Prospective, Multicenter, and Randomized Controlled Trial

Nasolabial folds (NLFs) are the most pronounced sign of facial aging. This study explored the efficacy and safety of polycaprolactone gel in treating Chinese patients with moderate-to-severe NLFs. Patients with moderate-to-severe NLF who wished to be treated by dermal fillers were recruited from three centers between July 2017 and September 2019. The randomizing ratio was 1:1 in the polycaprolactone group (polycaprolactone injection) or control group (sodium hyaluronate gel injection). The primary endpoint was the effectiveness rate of Wrinkle Severity Rating Score (WSRS) scores at 12 months after injection. The full-analysis set (FAS) and safety sets had 80 patients in the polycaprolactone group and control group, respectively. In the FAS, the effectiveness rate at 12 months in the polycaprolactone group was 88.8% compared with 23.8% in controls ( P < 0.001). The improvement in WSRS sustained during 12 months in the polycaprolactone group, while gradually vanished in the control group since 3 months after surgery. The global aesthetic improvement scale (GAIS) by investigator assessments was improved, much improved, or very much improved in all patients during follow-up, while the proportion of patients with a "no change " assessment gradually increased during follow-up after 6 months in the control group. The rates of injection-related adverse event (AE) and serve injection-related AE were 8.8 versus 11.3% and 0 versus 1.3% in the polycaprolactone group and control groups, respectively. Polycaprolactone gel injection is effective and safe to treat moderate-to-severe NLFs in Chinese patients.