Skin Quality and Safety Following Liquid-Form Polycaprolactone for Facial Rejuvenation: A Prospective Single-Arm Study.

INTRODUCTION

Prospective human evidence for liquid-form polycaprolactone (PCL) in facial rejuvenation is limited. We evaluated skin-quality changes and adverse events following treatment.

METHODS

Thirty participants received three monthly superficial subcutaneous (clinically intended subdermal) treatments in an uncontrolled prospective study. Skin mechanical, pigmentary, hydration, and sebum measurements were assessed through 6 months. The registered Antera primary outcomes are not included in this focused report. Instrumental measurements were also collected at 9 and 12 months but were excluded after calibration-related reliability concerns were identified during review of the late dataset; an institutional review board amendment subsequently restricted instrumental reporting to 6 months. Analyses used mixed-effects models; the corrected analysis of the delayed-to-immediate deformation ratio (R6) used restricted maximum likelihood and Bonferroni-adjusted baseline comparisons.

RESULTS

All 30 participants completed treatment; attendance was 29 at 1 month and 28 at 3 and 6 months. Maximum skin deformation (R0) decreased from 0.153 ± 0.062 to 0.112 ± 0.105 mm at 6 months. The delayed-to-immediate deformation ratio (R6) decreased from 0.307 ± 0.307 to 0.174 ± 0.277 (adjusted p = 0.038; overall p = 0.001). Hydration decreased. Bruising, swelling, and persistent postprocedural pain were reported; one swelling event was moderate and the remaining events were mild. All resolved without specific treatment. No serious adverse events were reported in the available safety summary.

CONCLUSION

Skin mechanical changes were observed following liquid-form PCL treatment. The uncontrolled design, variability, and retrospective restriction of instrumental reporting limit conclusions about efficacy, mechanism, and long-term durability. Larger controlled studies are needed.

TRIAL REGISTRATION: Thai Clinical Trials Registry, TCTR20250209003; retrospectively registered on February 9, 2025.