An Early Phase 1 interventional study of Botulinum toxin type A and Vehicle in Keloid, sponsored by University of California, San Diego. Completed at 1 site in United States. Open to participants aged 18 Years to 80 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-11-06.
Sponsored by University of California, San Diego · Early Phase 1, Interventional, and Treatment
Keloids are a common form of hypertrophic scars that by definition last beyond 6 months and grow beyond the site of initial injury. Keloids are a common complaint from patients in dermatology and cause significant functional impairment due to cosmetic disfigurement, itching and pain. Current treatment modalities include intralesional corticosteroids, chemotherapeutic agents and laser therapy. Initial reports have demonstrated that Botulinum toxin type A may be a viable treatment option for keloids that can reduce keloid size and reduce associated symptoms while having fewer side effects when compared to intralesional corticosteroid injection, which can cause unnatural blood vessel growth or skin thinning. To date, no study has carefully examined the efficacy of Botulinum toxin type A in treating keloids or its mechanistic effects on keloid biology. Our aim in this study is to pursue a rigorous, randomized control trial to assess the potential use Botulinum toxin type A to treat keloids. Efficacy will be objectively be mentioned by change in keloid size after treatment, along with subjective measures of patient satisfaction and symptoms, and finally physician rated scores. Also, samples from three patients will be analyzed in the laboratory setting to determine the underlying molecular mechanism behind the effects of Botulinum toxin type A on keloid biology.
138 studies on the registry are indexed under Keloid; 26 are open to participants now.
This study's enrollment of 10 is below the median of 30 across 109 interventional studies indexed under Keloid.
Browse Keloid studies →University of California, San Diego is the lead sponsor of 980 studies on the registry; 195 are open to participants now.
Of its 113 completed or terminated interventional studies of FDA-regulated products, 71 (63%) have results posted.
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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.
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Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will receive Botulinum toxin type A 5 units / cm3 with injections of 0.2mL spaced evenly 1cm apart within the treatment area (half of the keloid). Each treatment will consist of a maximum of 2 mL (10 injection sites, 50 unit total) of the study drug. Patients will undergo 3 treatments, 6 weeks apart.
Drug: Botulinum toxin type A
Participants will receive saline injections of 0.2mL spaced evenly 1cm apart within the placebo area (half of the keloid). Each treatment will consist of a maximum of 2 mL (10 injection sites) of the vehicle control (saline). Patients will undergo 3 treatments, 6 weeks apart.
Drug: Vehicle
Participants will receive Botulinum toxin type A 5 units / cm3 with injections of 0.2mL spaced evenly 1cm apart within the treatment area (half of the keloid). Each treatment will consist of a maximum of 2 mL (10 injection sites, 50 unit total) of the study drug. Patients will undergo 3 treatments, 6 weeks apart.
Participants will receive saline injections of 0.2mL spaced evenly 1cm apart within the placebo area (half of the keloid). Each treatment will consist of a maximum of 2 mL (10 injection sites) of the vehicle control (saline). Patients will undergo 3 treatments, 6 weeks apart.
Also known as: vehicle control (saline)
Change in Keloid volume
Keloid volume will be measured using the high resolution 3D imaging system (Cherry Imaging platform)
Time frame: Measurements obtained at 0 and 24 weeks.
Plan to share: Undecided — Publication will be submitted in a peer reviewed journal.
Ran from Mar 2022 to primary completion in May 2023, 14 months.
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This study is completed, as verified in Nov 2025. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Botulinum toxin type A
University of California, San Diego →