Safety, efficacy, and onset of a novel botulinum toxin type A (Nabota) for the treatment of glabellar frown lines: a single-arm, prospective, phase 4 clinical study

BACKGROUND: Safety, efficacy, and time to onset of effect of botulinum toxin type A is of importance to persons who seek improvement in glabellar frown lines, but this has not been well studied. The aim of this study was to determine the safety, efficacy, and onset of action of a newly developed botulinum toxin type A (Nabota) for the treatment of glabellar frown lines. METHODS: This was a single-arm, open-label, and phase 4 clinical study. Forty-two subjects with glabellar lines were treated with five times of intramuscular injection of 0.1 mL (4 U/0.1 mL) for a total of 20 U of Nabota. Efficacy and safety were assessed at 2, 3, 4, 5, and 14 days. Efficacy was assessed by the investigator and it was defined as a 1-point change on a 4-point scale. RESULTS: Improvement in glabellar frown lines at maximum frown was observed in 85.4% of subjects 2 days after administration. Improvement in glabellar lines at rest was observed in 51.2% of subjects 2 days after administration, and the proportion of subjects showing improvement increased with time. No severe adverse events were recorded. CONCLUSION: Onset of action was observed in the majority of subjects by 2 days after administration of Nabota. In addition, Nabota was found to be safe and effective for the treatment of glabellar frown lines.

The Regional Anatomy of the Corrugator Supercilii Muscle and Facial Nerve

Glabellar frown lines develop as a result of contraction of the corrugator supercilii muscles. These lines make look angry or aging. The neurotomy of facial nerve supplying corrugator supercilii muscle will prevent complications of the surgical technique and the reversibility of the nonsurgical technique. The regional anatomy of corrugator supercilii muscle is necessary for developing new technique. However, there is little information regarding the motor innervation of this muscle. The purpose of this study is to identify the regional anatomy of corrugator supercilii muscle and facial nerve and help to develop new technique of the neurotomy. We have dissected 6 Korean adult cadavers(12 sides). The motor innervation of this muscle was the temporal branch of facial nerve. The entry point of facial nerve into this muscle was found to be the inferolateral part. It was directly beneath the hair of lateral side of mid one-third of the eyebrow. The average distance between median plane and the entry point was 35.8mm. The measurement was not significantly different between right and left side. This study will be helpful for developing new technique of the neurotomy of motor nerve that supplies to corrugator supercilii muscle.