siRNA Microneedle Patches for Earlobe Keloid Post-Surgical Scars (SILK)

Small Interfering RNA (siRNA) Microneedle Patches on the Appearance of Earlobe Keloid Post-Surgical Scars: A Randomised Controlled Clinical Trial

The goal of this clinical trial is to evaluate whether small interfering RNA (siRNA) microneedle patches can improve the scar appearances of earlobe keloids treated with surgery. The main questions it aims to answer are:

• Do siRNA microneedle patches improve post-surgical scar appearance?
• Do siRNA microneedle patches improve keloid-related symptoms, recurrence, usability, and tolerability?

Researchers will compare standard treatment with CO₂ laser surgery followed by steroid injection with and without siRNA microneedle patches to see if the patches work to improve scar appearance.

Participants will:

• Undergo CO₂ laser ablation of an earlobe keloid
• Be randomly assigned to receive steroid injections alone every month for four doses, or to receive both steroid injections and siRNA microneedle patches.
• Visit the clinic at regular intervals for check ups and tests including photography

Study Overview

• Status: Not yet recruiting
• Conditions: Keloid of Ear Lobe
• Intervention / Treatment: Procedure: Carbon Dioxide (CO2) Laser Surgery; Drug: Intralesional Triamcinolone 40 mg/mL; Drug: Small interfering RNA (siRNA) Microneedle Patches

• Study Type: Interventional
• Enrollment (Estimated): 158
• Phase: Phase 2

Contacts and Locations

• Study Contact: Name: Kim Yao Ong; Phone Number: +6598327799; Email: ongkimyao@gmail.com

Study Locations

• Singapore
  • Singapore, Singapore, 308205
    • National Skin Centre
    • Contact: Research Coordinator; Phone Number: +6563506666
    • Principal Investigator: Suzanne Wei Na Cheng
    • Sub-Investigator: Hong Liang Tey
    • Sub-Investigator: Shan Sophie Carrie Cai
    • Sub-Investigator: Yisheng Wong
    • Sub-Investigator: Woo Chiao Tay
    • Sub-Investigator: Xiahong Zhao
    • Sub-Investigator: Kim Yao Ong

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• ≥21 years old
• Not pregnant, breastfeeding or lactating
• Able to give consent to participate in trial
• Keloid on the earlobe

• One keloid recruited per patient

  • For patients with bilateral earlobe keloids, only one earlobe keloid will be recruited (either left or right)
  • For patients with both anterior and posterior earlobe keloid on a single ear, only one side will be recruited (either anterior or posterior)
• Keloid must have protruded and extended beyond the margin of the initial injury
• Keloid base maximally 1cm by 1cm in size
• Patients who will not undergo additional ear piercing or surgical procedures during the follow-up period

Exclusion Criteria:

• Pregnant, breastfeeding or lactating
• Age <21 years old or unable to provide consent (e.g. from cognitive impairment)
• Keloid anywhere else on the ear apart from earlobe (including helix)
• Keloid base more than 1cm by 1cm in size
• Known allergy to any of the following: local anaesthetics, triamcinolone, siRNA microneedle patches, plasters, mepilex silver foam dressing, both penicillin and macrolide antibiotics
• Participants assessed to be uncooperative or unable to self-administer the interventions

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: CO2 laser surgery followed by intralesional steroid injection; In the active comparator arm, participants are first treated with CO2 laser surgery of the earlobe keloid. The first dose of intralesional steroid injection is given immediately to the wound bed post-surgery, followed by subsequent doses of intralesional steroid injection administered at monthly intervals for four doses in total.	Procedure: Carbon Dioxide (CO2) Laser Surgery; Carbon Dioxide (CO2) laser ablation of the earlobe keloid will be performed, followed by intralesional corticosteroid injections alone (active comparator arm) or with siRNA microneedle patches (experimental arm); Drug: Intralesional Triamcinolone 40 mg/mL; Intralesional triamcinolone 40mg/ml injection. The first dose is given immediately to the wound bed post-surgery, then at monthly intervals for four doses in total.
Experimental: CO2 laser surgery followed by intralesional steroids and siRNA microneedle patches; In the experimental arm, participants are first treated with CO2 laser surgery of the earlobe keloid. The first dose of intralesional steroid injection is given immediately to the wound bed post-surgery, followed by subsequent doses of intralesional steroid injection administered at monthly intervals for four doses in total. In addition, participants will apply siRNA microneedle patches for 10 hours per day for 90 days in total except on days where intralesional steroid injection is given to permit healing at puncture site.	Procedure: Carbon Dioxide (CO2) Laser Surgery; Carbon Dioxide (CO2) laser ablation of the earlobe keloid will be performed, followed by intralesional corticosteroid injections alone (active comparator arm) or with siRNA microneedle patches (experimental arm); Drug: Intralesional Triamcinolone 40 mg/mL; Intralesional triamcinolone 40mg/ml injection. The first dose is given immediately to the wound bed post-surgery, then at monthly intervals for four doses in total.; Drug: Small interfering RNA (siRNA) Microneedle Patches; Silencing or small interfering RNA (siRNA) are used to alter the expression of transforming growth factor secreted protein acidic and cysteine-rich (SPARC), a key mediator of wound fibrosis and keloid scar formation. Conjugating siRNA targeting SPARC mRNA with tyramine-modified gelatin to form a positively-charged nanoplex can help to enable siRNA protection against rapid in-vivo degradation, promoting uptake into fibroblasts via endocytosis, and enhacing targeted cellular delivery of the siRNA. These siRNA nanoplexes targeting SPARC mRNA are embedded in the tips of hyaluronic acid dissolvable microneedles (siRNA microneedles) to enhance transcutaneous drug delivery. In this study, participants in the experimental arm will apply siRNA microneedle patches daily for 10 hours a day in between monthly doses of intralesional corticosteroid injection for 90 days in total.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Post-surgical scar appearance measured using the Vancouver Scar Scale (VSS) score	The Vancouver Scar Scale (VSS) is a validated clinician-reported instrument that is a measure of scar severity comprising 4 domains assessing scar appearance and physical characteristics. The scale evaluates Vascularity (from 0 to 3), Pigmentation (from 0 to 2), Pliability (from 0 to 5) and Height (from 0 to 3). Each domain is assigned an individual score and combined to provide a total scar severity score ranging from 0 to 13, with higher values representing greater scar severity and poorer scar appearance. Changes in score over time may be used to assess response to treatment, with reductions in score representing clinical improvement. Score at baseline (post-surgical scar immediately post CO2 laser surgery) and at each review visit will be compared.	Visits at Day 0 (CO2 laser surgery), Day 15, Day 30, Day 60, Day 90, Day 120, Day 180, Day 270, Day 360 (through study completion)
Post-surgical scar appearance measured using Scar Cosmesis Assessment and Rating (SCAR) scale	The Scar Cosmesis Assessment and Rating (SCAR) scale is a validated clinician-reported instrument that is a measure of post-surgical scar quality comprising multiple domains assessing scar appearance, symptoms, and overall cosmetic outcome. The scale evaluates Scar Spread (from 0 to 4), Erythema (from 0 to 3), Dyspigmentation (from 0 to 2), Track or suture marks (from 0 to 1), Hypertrophy or atrophy (from 0 to 3), Overall impression (from 0 to 1), and patient rated bothersome itch and pain over the preceding 24 hours (Yes or No). Individual domain scores are combined to provide a total assessment of scar severity and cosmesis, with higher values representing poorer scar appearance and greater symptom burden. Changes in score over time may be used to assess response to treatment, with reductions in score representing clinical improvement. Score at baseline (post-surgical scar immediately post CO2 laser surgery) and at each review visit will be compared.	Visits at Day 0 (CO2 laser surgery), Day 15, Day 30, Day 60, Day 90, Day 120, Day 180, Day 270, Day 360 (through study completion)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from baseline on the Detroit Keloid Scale	The Detroit Keloid Scale (DKS) is a validated, clinician- and patient-reported instrument to assess the severity and treatment response of keloids. It is designed specifically for keloid scars and evaluates both objective scar characteristics and patient symptoms. The DKS has two components - the Observer Keloid Assessment (clinician-reported domains of location, height and surface area) and Patient Keloid Questionnaire (patient-reported domains of pruritus, pain, contracture/limitation to range of motion and quality of life). Scores from each domain are combined to provide a total assessment of keloid severity, with higher values representing greater disease severity and symptom burden. Changes in score over time may be used to assess response to treatment, with reductions in score representing clinical improvement. Score at baseline and at each review visit will be compared.	Visits at Recruitment (before treatment), Day 0 (CO2 laser surgery), Day 15, Day 30, Day 60, Day 90, Day 120, Day 180, Day 270, Day 360 (through study completion)
Presence of recurrence	Keloid recurrence will be defined by Height score of at least 1 on the Observer Keloid Assessment of the DKS. The keloid wound bed will be flat post-CO2 laser surgery and increase in height is taken to be an early marker of keloid recurrence.	At first detection of recurrence on any review visits (up to 1 year follow up, through study completion)
Recurrence rate	The recurrence rate in each arm will be measured. It is calculated as the number of patients with keloid recurrence divided by the total number of patients in the treatment arm.	At first detection of recurrence on any review visits (up to 1 year follow up, through study completion)
Time to recurrence (for patients with earlobe keloid recurrence)	For patients with recurrent earlobe keloid, time to earlobe keloid recurrence will be measured. It is calculated as the time from CO2 laser surgery (denoted as day 0) to time of first detection of keloid recurrence in days.	From day of CO2 laser surgery to day of first detection of keloid recurrence (up to 1 year follow up, through study completion)
Secondary rescue treatment (for patients with earlobe keloid recurrence)	For patients with recurrent earlobe keloid, secondary rescue treatment will be measured in terms of treatment modality offered (such as repeat CO2 laser surgery, intralesional steroid injection) and response (resolution, partial response, no response).	Visits at Day 15, Day 30, Day 60, Day 90, Day 120, Day 180, Day 270, Day 360 visits, starting from first detection of recurrence (through study completion)
Adverse effects	Patients will be monitored for any adverse effects from the CO2 laser surgery, intralesional corticosteroid injections and/or the siRNA microneedle patches, such as but not limited to - dyspigmentation, skin atrophy, telangiectasia, edema, infection, contact dermatitis, ulceration, necrosis.	Visits at Day 0 (CO2 laser surgery), Day 15, Day 30, Day 60, Day 90, Day 120, Day 180, Day 270, Day 360 (through study completion)
Patient-reported usability of siRNA microneedle patches (for patients in experimental arm only)	Patients in the experimental arm who will receive the siRNA microneedle patches will fill in a questionnaire on the usability of the siRNA microneedle patches. The questionnaire evaluates 1) degree of acceptability of microneedle patches (four options of very acceptable, acceptable fair or not acceptable), 2) whether patients will use the microneedles patch again in the future to treat any future post-surgcial scars (Yes/No response, with further open ended elaboration), and 3) areas of improvement to suggest if any (optional open ended).	Visits at Day 60, Day 90, Day 120 (review visits while patients in experimental arm are being treated with microneedle patches)

Collaborators and Investigators

• Sponsor: Ong Kim Yao
• Collaborators: National Healthcare Group, Singapore
• Investigators: Principal Investigator: Suzanne Wei Na Cheng, National Skin Centre

Study record dates

Study Major Dates

• Study Start (Estimated): June 1, 2026
• Primary Completion (Estimated): December 1, 2027
• Study Completion (Estimated): December 1, 2027

Study Registration Dates

• First Submitted: May 13, 2026
• First Submitted That Met QC Criteria: May 13, 2026
• First Posted (Actual): May 19, 2026

Study Record Updates

• Last Update Posted (Actual): May 22, 2026
• Last Update Submitted That Met QC Criteria: May 19, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: RNA; keloid; scars; ear; microneedles; small intefering RNA; earlobe
• Additional Relevant MeSH Terms: Pathologic Processes; Connective Tissue Diseases; Fibrosis; Collagen Diseases; Pathological Conditions, Signs and Symptoms; Skin and Connective Tissue Diseases; Cicatrix; Keloid; Therapeutics; Surgical Procedures, Operative; Nucleic Acids; Nucleic Acids, Nucleotides, and Nucleosides; Inorganic Chemicals; Oxides; Oxygen Compounds; Gases; Ablation Techniques; Carbon Compounds, Inorganic; RNA, Antisense; Antisense Elements (Genetics); RNA; RNA, Small Untranslated; RNA, Untranslated; Laser Therapy; Carbon Dioxide; RNA, Small Interfering
• Other Study ID Numbers: NHG Health DSRB Ref 2025-1631

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Sharing Time Frame: De-identified individual participant data will be made available beginning 12 months following publication of the primary study results and ending 3 years thereafter.
• IPD Sharing Access Criteria: Access to de-identified individual participant data may be granted to qualified researchers for scientifically sound research proposals approved by the study investigators and sponsoring institution. Requests must include a research proposal and statistical analysis plan. Data sharing is subject to applicable institutional, ethical, and regulatory approvals, and a signed data sharing agreement may be required prior to release of data. Data will be provided in a de-identified format through secure institutional channels upon approval of request.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No