Multidimensional Comparison of Abobotulinumtoxin A 100 Units and Neubotulinumtoxin A 33.33 Units for the Treatment of Hemifacial Spasm: A 50-Week Prospective, Double-Blind, Randomized Crossover Controlled Trial

Comparative evidence across repeated botulinum toxin treatment cycles for hemifacial spasm (HFS) remains limited. This 50-week double-blind randomized crossover trial compared Abobotulinumtoxin A 100 U (Abo-BoNT-A) with Neubotulinumtoxin A 33.33 U (Neu-BoNT-A) across multiple dimensions, including improvement frequency, magnitude, time course, patient impact, harms, and cost in 92 participants. Each formulation was scheduled for two consecutive 12-week periods, with a 2-week washout before crossover. Although Total Intensity Score did not demonstrate Neu-BoNT-A noninferiority, exploratory diary-defined HFS-free improvement during Days 2–14 occurred in 48.0% versus 34.1% of Abo-BoNT-A and Neu-BoNT-A treatment records (adjusted odds ratio, OR 1.89; 95% CI, 1.26–2.84; nominal p = 0.0021). Among responders, time to peak improvement and post-peak duration did not differ significantly. Selected exploratory symptom trajectories differed, whereas cycle-average burden and patient-reported outcomes showed no consistent differences. Eyelid ptosis occurred in 4.3% versus 0.5% of reported exposures (unadjusted paired p = 0.039). Under vial sharing, acquisition costs were USD 81.52 versus USD 30.78 per treatment. These multidimensional findings suggest an exploratory response–safety–cost trade-off beyond average symptom scores. Trial registration: NCT04589364.