A Phase 2 interventional study of Intralesional Metformin and Intralesional Triamcinolone Acetonide in Keloids, sponsored by Al-Azhar University. Completed at 1 site in Egypt. Open to participants aged 18 Years to 45 Years. Per ClinicalTrials.gov, last updated 2026-11-06.
Sponsored by Al-Azhar University · Phase 2, Interventional, and Treatment
The goal of this clinical study was to compare the efficacy and safety of intralesional metformin compared to intralesional triamcinolone acetonide in the treatment of keloids.
The study included 30 participants with keloids. The main questions were:
Each participant received metformin injection in one lesion and triamcinolone acetonide injection in the other lesion.
Researchers assessed the scars using clinical examinations and ultrasound. They also monitored side effects during treatment and follow-up.
The study aimed to determine whether intralesional metformin could be an alternative treatment for keloids.
Keloids are raised scars that extend beyond the boundaries of the original skin injury due to excessive scar tissue formation. Keloids may cause itching, pain, tenderness, and cosmetic concerns. Treatment remains challenging, and recurrence may occur despite treatment.
Intralesional triamcinolone acetonide is a commonly used treatment for keloids. Metformin is a medication primarily used to treat type 2 diabetes mellitus. Metformin may influence biological pathways involved in inflammation and fibrosis, providing a scientific rationale for investigating intralesional metformin as a potential treatment for keloid scars.
The study aimed to compare the efficacy and safety of intralesional metformin with intralesional triamcinolone acetonide in the treatment of keloids The study included 30 Egyptian patients with multiple keloid scars attending the Dermatology Outpatient Clinics at Al-Zahraa University Hospital, Al-Azhar University, Cairo, Egypt. Before treatment, all participants underwent comprehensive clinical evaluation, including detailed medical history taking and general and dermatological examinations. Information regarding scar onset, duration, progression, anatomical location, associated symptoms, previous treatments, and relevant cutaneous or systemic conditions was documented.
Each selected lesion was assessed clinically, and standardized digital photographs were obtained using a 48-megapixel iPhone 14 Pro Max camera under consistent lighting conditions and patient positioning. Baseline scar severity was assessed clinically. Radiological assessment of scar thickness was performed using ultrasonography.
Before each injection session, the treatment area was cleansed with 70% isopropyl alcohol and subsequently rinsed with sterile normal saline. Local anesthesia was achieved by subcutaneous infiltration of lidocaine hydrochloride (50 mg/5 mL; Pharco International Company) around the lesion before drug administration.
Both the metformin- and triamcinolone-treated lesions received intralesional injections at three-week intervals for a maximum of six sessions or until complete clinical flattening of the scar was achieved. All participants completed the six planned treatment sessions, as no lesion achieved complete clinical flattening before completion of the treatment course.
Throughout the study period, participants were instructed not to use additional keloid-directed treatments, including silicone sheets or gels, pressure therapy, other intralesional injections, topical treatments, or physical therapies. This restriction was maintained throughout the treatment and follow-up periods to minimize potential confounding effects on the study outcomes.
138 studies on the registry are indexed under Keloid; 26 are open to participants now.
This study's enrollment of 30 is close to the median of 30 across 109 interventional studies indexed under Keloid.
Browse Keloid studies →Al-Azhar University is the lead sponsor of 531 studies on the registry; 172 are open to participants now.
Of its 5 completed or terminated interventional studies of FDA-regulated products, 0 (0%) have results posted.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
All participants with at least two comparable keloid lesions received intralesional metformin in one randomly selected lesion and intralesional Triamcinolone in the other lesion. Both lesions were treated during the same sessions.
Drug: Intralesional Metformin · Drug: Intralesional Triamcinolone Acetonide
The metformin solution was prepared in the Department of Pharmaceutics and Pharmaceutical Technology, Faculty of Pharmacy, Heliopolis University. A 200 mM metformin solution (25.8 mg/mL) was prepared by dissolving metformin powder in water for injection. Propylene glycol (15%, v/v) was incorporated as a cosolvent and penetration enhancer. The pH was adjusted to 7.4 using disodium hydrogen phosphate, and the solution was stirred until complete dissolution was achieved. Sterilization was performed. Intralesional injection of Metformin solution was done using a dose of 0.1 mL per centimeter of lesion length until uniform blanching of the lesion was observed. The maximum injection volume was 1-2 mL per lesion per treatment session, depending on lesion size. Participants received treatment every 3 weeks for up to 6 sessions.
The commercial triamcinolone acetonide preparation used in the study was Epirelefan® (40 mg/mL; EIPICO, Egypt). The original preparation was diluted with an equal volume of sterile 0.9% normal saline to obtain a concentration of 20 mg/mL. For smaller lesions, the 20 mg/mL preparation was further diluted 1:1 with sterile 0.9% normal saline to obtain a final concentration of 10 mg/mL, whereas the 20 mg/mL concentration was used for larger or thicker lesions. A dose of 0.1 mL per centimeter of lesion length was injected intralesionally until uniform blanching of the lesion was observed. The maximum injection volume was 1-2 mL per lesion per treatment session, depending on lesion size. Participants received injections every 3 weeks for up to 6 sessions.
Change from baseline in the Vancouver Scar Scale (VSS) Score at Week 19
• The Vancouver Scar Scale (VSS) evaluated scar vascularity (0 = normal, 1 = pink, 2 = red, 3 = purple), pigmentation (0 = normal, 1 = hypopigmentation, 2 = mixed, 3 = hyperpigmentation), pliability (0 = normal, 1 = supple, 2 = yielding, 3 = firm, 4 = ropes, 5 = contracture), and height (0 = flat, 1 = \<2mm, 2 = 2-5mm, 3 = \>5mm). Total scores ranged from 0 to 14, with 0 indicating normal skin and 14 indicating the most severe scarring. The reduction in the total VSS score was used to categorize treatment response into four clinical categories: poor (1-25% reduction), fair (26-50% reduction), good (51-75% reduction), or excellent (\>75% reduction). Changes were compared between metformin-treated and triamcinolone-treated lesions. Assessments were supported by standardized digital photographs obtained using Identical camera settings, lighting conditions, and patient positioning. Changes were compared between metformin-treated and triamcinolone-treated lesions.
Time frame: Baseline and Week 19 (one month after the 6th treatment session)
Change From Baseline in Keloid Thickness and Length Assessed by Ultrasonography at Week 19
Objective treatment efficacy was assessed by high-resolution ultrasonography using a Philips Affiniti 70 ultrasound system (Philips, Amsterdam, Netherlands) equipped with a 10-MHz linear-array transducer. The ultrasonographic parameters evaluated were keloid thickness and length, both measured in millimeters. The change was calculated by subtracting the baseline score from the final clinical score obtained at the assessment visit 1 month after the last (6th) treatment session. Changes were compared between metformin-treated and triamcinolone-treated lesions.
Time frame: Baseline and Week 19 (one month after the 6th treatment session)
Patient Satisfaction Score at Week 19
Patient satisfaction was evaluated using a 5-point scale ranging from 0 to 4. On this scale, a score of 0 indicates "not satisfied"; 1 = mild satisfaction; 2 = moderate satisfaction; 3 = good satisfaction; and 4 = excellent satisfaction (which correlated with more than 75% perceived clinical improvement).
Time frame: Week 19 (one month after the 6th treatment session)
Number of Participants with Treatment-Related Adverse Events through Week 27
Safety and tolerability were evaluated by documenting the total number of participants who developed side effects after injection into the treated keloid lesions. Monitoring was performed by the investigator at each injection session (weeks 0, 3, 6, 9, 12, and 15) and monthly for 3 months post-treatment. Specific adverse events monitored included pain, swelling, infection, pigmentary changes, ulceration, and skin atrophy. A participant was counted if they experienced one or more of these events at any point during the evaluation period.
Time frame: Baseline up to Week 27 (three months after the 6th treatment session).
Number of Participants Experiencing Recurrence From Week 15 up to Week 27
Keloid recurrence was evaluated through clinical examination to detect the reappearance of active keloid tissue growth. Lesions that achieved complete clinical healing or flattening at the end of the treatment sessions were monitored longitudinally. Recurrence is defined as an increase in volume, height, or vertical regrowth of the scar tissue.
Time frame: From Week 15 up to Week 27 (three months after the 6th treatment session).
Plan to share: No — Individual participant data will not be shared publicly to protect the privacy and confidentiality of the participants, in accordance with the institutional ethical guidelines. De-identified clinical data and statistical summaries will be available only upon reasonable request to the corresponding author, subject to approval by the institutional review board
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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