for people ages 18-80 (full criteria)
Healthy Volunteers
healthy people welcome
at San Diego, California
study started
completion around
Principal Investigator
by Arisa Ortiz
Headshot of Arisa Ortiz
Arisa Ortiz



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.


Keloid, Botulinum Toxins, Type A Botulinum Toxins, abobotulinumtoxinA, Botulinum toxin type A, Vehicle


You can join if…

Open to people ages 18-80

  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.

You CAN'T join if...

  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


  • University of California San Diego
    San Diego California 92122 United States

Lead Scientist at UCSD

  • Arisa Ortiz
    Associate Clinical Professor, Dermatology, Vc-health Sciences-schools. Authored (or co-authored) 39 research publications


in progress, not accepting new patients
Start Date
Completion Date
University of California, San Diego
Phase 1 Keloid Research Study
Study Type
About 10 people participating
Last Updated