Botulinum Toxin is a Potential Prophylactic Therapy for Minimizing Post-excisional Scarring (Allergan Botox Scar Study)

Botulinum Toxin is a Potential Prophylactic Therapy for Minimizing Post-excisional Scarring: A Double Blinded, Randomized Controlled Trial

Dermatological surgeons wear many hats to care for subjects with skin cancer. While their role in cancerous tissue removal results in superior cure rates, there is also a need for skilled excisional repair and effective wound healing regimens so the subject can heal with the least amount of scarring necessary. As such, numerous techniques have been developed for reducing the morbidity associated with excessive scarring. Various flaps and grafts allow the surgeon to approximate skin texture, thickness and adnexa with respect to the residual surrounding tissue. Optimal cosmetic and functional outcomes require close wound approximation with minimal static tension along the wound edge. In addition, there are post-operative wound care techniques that range from special dressings to cosmetic scar modification. To date, most surgical wounds are allowed to heal at least partially before scar revision or modulation is attempted.

Botulinum toxin presents a unique opportunity for surgeons to affect scar formation throughout the duration of the healing process. These effects are likely independent and adjunctive to any and all wound care techniques, and are primarily attributed to a reduction in dynamic tension on the wound edges. Most importantly, botulinum toxin's one time dosing requirements with respect to reduced scar formation precludes the variance inherent to standard wound care practices.

Therefore, it has been proposed that for selected subjects, botulinum toxin may be a safe, effective and reliable means for improved post-excisional repair outcomes. Botulinum toxin has been investigated as an inhibitor of excessive, post-excisional scar formation in plastic surgery and Otorhinolaryngology literature. However, these promising studies have yet to combine objective assessment measures of human scar formation in a randomized controlled trial. In addition, there are currently no formal studies of botulinum toxin as a prophylactic against excess scarring in the dermatological literature. Fortunately, Botulinum toxin dosing in the forehead for the purposes of inhibiting excessive scar formation is comparable to the amount given for cosmetic purposes, which is commonplace in dermatology and well-studied.

This study will attempt to assess the efficacy of Botulinum toxin as a prophylactic treatment in post-excisional repairs for the purpose of preventing excess scar formation. The end points will be the evaluation of each scar using the Manchester Scar Scale.

All MSS and mMSS assessments will be performed in a standardized fashion. The mMSS assessments will be blinded and performed by board-certified dermatologists in the Department of Dermatology, Faculty Practice Associates, Icahn School of Medicine at Mount Sinai, New York City.

Inclusion Criteria:

• English-speaking adults at least 18 years old.
• Subjects must be scheduled for an excision of forehead skin due to any etiology, with a same day, single stage closure planned as the most likely surgical repair.
• Subjects must be able to read, sign, and understand the informed consent.
• Subject is willing and able to participate in the study as an outpatient, making several visits to the study center during the treatment and follow-up periods and to comply with all study requirements including concomitant medication and other treatment restrictions.
• If subject is a female of childbearing potential she must have a negative urine pregnancy test result prior to study treatment initiation and must agree to use an approved method of birth control while enrolled in the study.

Exclusion Criteria:

• Subjects with an unstable medical condition as deemed by the clinical investigator, including review of the subject's prior and current medications.
• Subjects with Myasthenia gravis, Lambert-Eaton Syndrome or other neuromuscular disorder.
• Subjects taking medications that may alter the function of neuromuscular junctions (i.e. aminoglycoside antibiotics)
• Women who are pregnant, lactating, or planning to become pregnant during the study period.
• Subjects who have a history of keloids.
• Known allergy to botulinum toxin.
• Subjects who are not able to be closed with a same day, single stage technique.