A Randomized, Comparative Study to Evaluate Efficacy and Safety of Two Injection Volumes of AbobotulinumtoxinA in Treatment of Glabellar Lines

Abstract

BACKGROUNDDifferent volumes of 0.9% NaCl may be used to reconstitute abobotulinumtoxinA yielding an injection volume that ranges from 0.05 to 0.1 mL per injection point for treatment of glabellar lines.OBJECTIVETo evaluate the efficacy, safety, and subject satisfaction of 2 different injection volumes to deliver the same unit dose of abobotulinumtoxinA for treatment of glabellar lines.MATERIALS AND METHODSThis randomized comparative study was conducted using 2 different reconstitution volumes to deliver a fixed unit dose of 10 Speywood units (sU) of abobotulinumtoxinA in either 0.05 mL (labeled volume) or 0.1 mL (twofold volume) per injection point. Evaluations included wrinkle severity, neurophysiological assessment by compound muscle action potential (CMAP), and subject satisfaction.RESULTSUse of either injection volume of abobotulinumtoxinA resulted in the early onset of effect, high effectiveness, and long duration of effect. The safety profile and injection pain levels were similar in both groups. The twofold injection volume was shown to be noninferior to the labeled injection volume based on CMAP results.CONCLUSIONA twofold increase in injection volume to 0.1 mL per injection point to deliver 10 sU of abobotulinumtoxinA is effective and safe.

Botulinum Toxin in Aesthetic Medicine: Myths and Realities

“…Indeed, a recent randomized, comparative study evaluating the efficacy and safety of injection volumes of 0.05 or 0.1 mL per injection point (to deliver 10 units of Azzalure) for the treatment of glabellar lines found no significant differences; both injection volumes resulted in comparable onset and duration of effect, frequency and severity of adverse events and similar patient satisfaction. 63 …”

An Italian experience of a new personalized injective protocol (Botutouch) for botulinum toxin application in aesthetic medicine

“…Moreover, also in the recent randomized comparative study of Punga et al, 13 a 2‐fold injection volume was shown to be effective and safe as well as the labeled injection volume.…”

“…However, some studies have shown that a higher dilution remains effective and safe. 12,13 Since 2013, an innovative protocol has been developed in our clinic that works on a double dilution volume, identifies the injection site according to the specific anatomical-functional characteristics of each patient's musculature and applies a gentle massage to the area injected to optimize the spread of the toxin in the muscle. In this article, we want to describe our personal experience.…”

“…To date, various BoNTA dilutions have been proposed in literature, and this is the reason why in the clinical practice the applied dilution is at the discretion of the clinician. However, some studies have shown that a higher dilution remains effective and safe 12,13 . Since 2013, an innovative protocol has been developed in our clinic that works on a double dilution volume, identifies the injection site according to the specific anatomical‐functional characteristics of each patient's musculature and applies a gentle massage to the area injected to optimize the spread of the toxin in the muscle.…”

Neurophysiological Measures of Efficacy and Safety for Botulinum Toxin Injection in Facial and Bulbar Muscles: Special Considerations

“…CMAP studies demonstrate the return of 20% of normal activity in patients as soon as seven days after BoNT injection in the EDB muscle [ 60 ]. Interestingly, in the glabellar muscles a substantial reduction in the CMAP parameter was still seen at six months after treatment, with values reduced to approximately 60% of the baseline amplitude in the labelled volume and to a numerically greater reduction of approximately 50% in the twofold volume group [ 61 ]. The reduction in CMAP was greater in the group who received the twofold injection volume at every time point, including time to the onset of effect and duration.…”