Botulinum type A injections are widely used across the dermatology and aesthetic medicine specialties. At the Fall Clinical Dermatology Conference 2021, Mark S Nestor, MD, PhD, highlights how to optimize the neurotoxin to improve patient care.
While botulinum type A acts identically and can come in commercial multiple forms, how does it compare with regards to clinical aspects?
Mark S. Nestor, MD, PhD, dermatologist and executive director of aesthetics at the Hair and Regenerative Medicine (FRED), Director for Center for Cosmetic Enhancement and the Center for Clinical and Cosmetic Research, Aventura, Florida, and voluntary professor at the Department of Dermatology and Cutaneous Surgery Department of Surgery, Division of Plastic Surgery, University of Miami Miller School of Medicine, Miami, Florida, dove into that question at Fall Clinical Dermatology Conference 2021, held October 21-24 in Las Vegas, Nevada.1
Nestor emphasized that understanding the clinical science of botulinum type A will help optimize patient care.
Nestor explained 8 postulates about botulinum type A:2,3
Postulate 1: All Type A toxins act identically.
Postulate 2: The efficacy of treatment is based on the equation between toxin and receptor. The clinical efficacy is influenced by molecular potency and patient attributes including muscle mass, gender, age, and ethnicity.
Postulate 3: The efficacy, onset, and duration of treatment are all functions of molecular potency.
Postulate 4: The molecular potency is hard to objectively quantify.
In the double-blinded Frontalis Trial,4 22 female patients (ages 19-63) were treated for severe frontalis rhytids at maximum elevation with either 5 units of AbobotulinumtoxinA (ABO) (Dysport; Ipsen Biopharmaceuticals) or 2 units of OnabotulinumtoxinA (ONA) (Botox; Allergan) at 5 contralateral sites. The units were identical volumes of 0.04 ml: Diluted with 2.4 ml of non-preserved saline (NS) per 300 units of ABO and 2.0 ml of NS per 100 units of ONA: a 2.5:1 unit ratio, according to Nestor.
It was found that the overall median onset of ABO was 1.8 days and ONA was 3.8 days with the duration of the procedure lasting a median of 104 days vs 84 days, respectively.
Postulate 5: The increased molecular potency, to a certain point, will decrease the time to onset and increase duration of effect. Nestor broke this down to molecular potency quotient (MPQ) as the amount of molecular potency units divided by the cost. MPQ and molecular potency of ABO was examined in a clinical trial, Nestor explained, which found that the data was consistent with molecular potency showing early onset and long duration at comparable dosing (high MPQ).7
Postulate 6: Toxin diffusion is a misnomer and toxin spread—physical movement of toxin from the original injection site—is dependent on the technique.
Postulate 7: Optimal reconstitution volume can improve distribution and can then improve onset, efficacy, and duration of effect. Nestor showed that multiple factors can impact the treatment such as the various standard methods for each botulinum toxin type A, off-label volumes vary from 1 to 5 units, and volumes that are too small or too large can widely change the effect of the toxin.
Postulate 8: An increased number of injection sites can optimize toxin distribution and improve onset, efficacy, and duration of effect.
Nestor concluded his presentation with the notion that fully understanding the clinical science of botulinum toxin type A will help physicians compare the toxins available while optimizing patient care.
Nestor is a consultant for Aerolase, Croma Pharma GmbH, DermTech, Fastox Pharma, Ferndale, Ipsen Biopharmaceuticals, Kimera, Kyrstal Biotech, Mediwound, Novaestiq Corp, Plasmend, Pulse Biosciences, Revian, Rohrer Aesthetics, Seaspire, Sensus Healthcare, Sirnaomics, and Suneva Medical.
He has received research grants from Arcutis Biotherapeutics, Biofrontera, Bioregenerative Aesthetics, Inc., BirchBioMed, Brickell Biotech, Croma Pharma GmbH, DermTech, DUSA Pharmaceuticals, Eirion Therapeutics, Ferndale, Galderma, Krystal Biotech, Mediwound, Merz Pharma, miRagen Therapeutics, Plasmend, Pulse Biosciences, Sirnaomics, SkinJect, Inc, and Sueva Medical.
He is on the advisory board for Allergan, Biofrontera, BirchBioMed, Castle Biosciences, Eirion Therapeutics, Fastox Pharma, Ferndale, Galderma, Novaestiq Corp, Sensus Healthcare, and Sirnaomics. He is a speaker for Sensus Healthcare and a shareholder of Strathspey.