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Updated: Oct 21, 2025

Isolation, Culture, and Characterization of Primary Dermal Fibroblasts from Human Keloid Tissue
Published on: July 28, 2023
A Randomized, Double-Blind, Active- and Placebo-Controlled Trial Evaluating a Novel Topical Treatment for Keloid
Abstract:
Keloid and hypertrophic scars are fibroproliferative disorders resulting from abnormal wound healing in genetically susceptible individuals. Current therapies are often ineffective. Kynurenine shows promise as a topical treatment for keloids and hypertrophic scars. In this study, healthy adult male and female subjects seeking treatment for mature keloid scars were enrolled. Subjects were randomized in double-blind fashion to receive kynurenic acid 0.5% (FS2) cream (Group 1), an active onion extract comparator treatment (Group 2), or the inactive vehicle (Group 3). Each treatment was applied twice-daily. Qualitative assessments were made using the Vancouver Scar Scale (VSS), as well as the Patient and Observer Scar Assessment Scales (POSAS). Among subjects in Group 1, there was a substantial decrease in mean PGSS scores after 30 days of treatment that continued to trend downward, becoming significant versus Group 2 at days 90 and 180 (P<0.05) and versus Group 3 at day 180 (P<0.01). Based on mean VSS scores, subjects in Group 1 achieved beneficial effects that became significant versus Group 2 at day 90 (P<0.01), day 120 (P<0.05), and day 180 (P<0.001) and versus Group 3 at day 180 (P<0.05). There were no significant improvements in Groups 2 or 3. There were no adverse events or local skin reactions. The twice-daily application of FS2 Cream represents a potentially new and effective treatment for mature keloid scars. J Drugs Dermatol. 2021;20(9):964-968. doi:10.36849/JDD.6197.
Insights
Topical kynurenic acid cream (FS2) significantly improved mature keloid scars compared to a comparator and placebo. This new treatment showed no adverse events, offering a promising option for scar management.
Area of Science:
- Dermatology
- Wound Healing Research
- Pharmacology
Background:
- Keloid and hypertrophic scars are fibroproliferative disorders linked to abnormal wound healing.
- Existing therapies for these scars often yield suboptimal results.
- Kynurenine demonstrates potential as a topical therapeutic agent for keloid and hypertrophic scars.
Purpose of the Study:
- To evaluate the efficacy and safety of topical kynurenic acid (FS2) cream in treating mature keloid scars.
- To compare FS2 cream against an active onion extract comparator and an inactive vehicle.
Main Methods:
- A double-blind, randomized study enrolled subjects with mature keloid scars.
- Participants applied FS2 cream (0.5%), onion extract, or vehicle twice daily.
- Scar assessments utilized the Vancouver Scar Scale (VSS) and Patient and Observer Scar Assessment Scales (POSAS).
Main Results:
- FS2 cream demonstrated significant improvements in scar appearance and patient/observer ratings compared to the comparator and vehicle.
- Statistical significance was achieved at various time points for both VSS and POSAS scores.
- No adverse events or local skin reactions were reported with FS2 cream application.
Conclusions:
- Twice-daily application of FS2 Cream is a potentially novel and effective treatment for mature keloid scars.
- FS2 cream offers a safe therapeutic option for managing challenging scar conditions.
- Further research may validate kynurenine-based therapies for fibroproliferative scar disorders.
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