Examining the Therapeutic Potential of Botulinum Toxin Type A in the Treatment of Keloids

University of California San Diego

Status and phase: Completed; Early Phase 1

Conditions: Keloid

Treatments: Drug: Botulinum toxin type A; Drug: Vehicle

Study type: Interventional

Funder types: Other

Identifiers

NCT05330078

201088

Details and patient eligibility

About

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.

Enrollment: 10 patients

Sex: All

Ages: 18 to 80 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

1. Adults aged 18 to 80
2. History of keloid scar for at least 12 months
3. Absence of keloid treatment for past 12 months
4. Participant must have a keloid scar of at least 4cm in length.
5. Participants who score at least 8 or higher on the Vancouver Scar Scale
6. Subjects who score 5 (neither satisfied nor dissatisfied) to 10 (maximally dissatisfied) on the patient subjective score of dissatisfaction with keloid.
7. Participants must be in stable health, as confirmed by medical history, per investigator judgment
8. Participants must be able to read, sign, and understand the informed consent
9. Participants must be willing to avoid any other treatments to the keloid that will be treated including corticosteroid injections, surgical excision, chemotherapeutic injection, lasers, light-based therapy, radiation therapy, cryotherapy, or pressure therapy, during the study period.

Exclusion criteria

1. Pregnant women
2. Keloids on face, neck or scalp
3. History of hypersensitivity to botulinum toxin
4. Ongoing or planned treatment with chemotherapy, radiation, isotretinoin, cytokine-based immunotherapies
5. Any planned surgery during study period
6. Known diagnosis of insulin dependent diabetes mellitus
7. Patients being treating with dupilumab for any indication
8. Patients taking aminoglycoside antibiotics
9. Patients with pre-existing neuromuscular disorders
10. Patients with infection around potential injection sites

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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10 participants in 2 patient groups, including a placebo group

Keloid treatment with botulinum toxin type A

Experimental group

Description:

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.

Treatment:

Drug: Botulinum toxin type A

Keloid treatment with vehicle control (saline)

Placebo Comparator group

Description:

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.

Treatment:

Drug: Vehicle