NCT05072821

Botulinum Toxin Type a Injection to Prevent Keloid Recurrence

Immediate Injection of Botulinum Toxin Type a After Keloid Scar Revision to Prevent Keloid Recurrence: a Prospective, Split-scar, Double-blind, Randomized Controlled Study

• Status: Completed
• Phase: Phase 4
• Study type: Interventional
• Enrollment: 28 (actual)
• Sponsor: National Cheng-Kung University Hospital · Academic / Other
• Sex: All
• Age: 20 Years
• Healthy volunteers: Accepted

Summary

The prospective, split-scar, double-blind, randomized controlled study will enroll the patients who are older than 20 years with progressive keloid lesion which is symmetric. Botulinum toxin A will be injected into half of each keloid revision wound immediately after skin closure. The scars will be assessed at 1-year follow-up with Vancouver Scar Scale (VSS), Patient and Observer Scar Assessment Scale (POSAS), and the Cutometer.

Detailed description

Continuous variables will be reported as the mean ± standard deviation(SD). Each aspect of the VSS score, POSAS score, and the Cutometer parameters of each scar half between the BTA and control groups will be analyzed longitudinally using the paired t test. The interrater consistency will be evaluated using the Spearman rho. All analyses will be performed with IBM SPSS Version 23.0 (IBM Corp., Redmond, Wash.). A value of p \< 0.05 is considered to indicate statistical significance. The sample size was calculated based on the results of the investigators' aforementioned study published in 2019. Thirty patients underwent keloid revision and then received radiation therapy based on our treatment protocol. The postoperative Vancouver Scar Scale score was 4.15 ± 1.74. If treatment could improve VSS score by 1, which was considered clinically significant, approximately 26 patients would have been necessary to provide a result with a real significance (using the same SD and considering the standard α error of 0.05 and a power of 0.8). Assuming a 20% non-compliance rate for follow-up evaluation, the sample size was increased to 32 patients.

Conditions

• Scar Keloid

Interventions

Type	Name	Description
DRUG	Botulinum Toxin Type A Injection [Botox]	After the whole surgical procedures of keloid revision are done, the participants will receive Botulinum Toxin type A (BTA) injection. The investigators split the scar into the right side and the left side. BTA and 0.9% saline, respectively, are used for the two arms of the study. Vials containing 100 units of BTA (BotoxⓇ, Allergan) are mixed with 2mL 0.9% injectable saline. The injection depth will be the intradermal layer. Injections will be performed with a 30-gauge needle and 1 mL syringe. Just before skin closure, the entire scar was treated, with sides randomized to receive treatment with either BTA or 0.9% normal saline. The dosage is 8 units / cm based on aforementioned studies. The maximal dose won't exceed 100 units.
DRUG	0.9% Sodium Chloride Injection	After the whole surgical procedures of keloid revision are done, the participants will receive 0.9% saline injection. The investigators split the scar into the right side and the left side. BTA and 0.9% saline, respectively, are used for the two arms of the study. Only 0.9% saline is injected on the control side. The injection depth will be the intradermal layer. Injections will be performed with a 30-gauge needle and 1 mL syringe. Just before skin closure, the entire scar was injected, with sides randomized to receive treatment with either BTA or 0.9% normal saline. The dosage is 0.16 mL / cm.

Timeline

• Start date: 2020-10-13
• Primary completion: 2024-03-20
• Completion: 2024-03-20
• First posted: 2021-10-11
• Last updated: 2024-11-07

Locations

1 site across 1 country: Taiwan