Related Experiment Video
Updated: Jan 27, 2026
Randomized, Triple-Blind, and Parallel-Controlled Trial of Transcranial Direct Current Stimulation for Cognitive Rehabilitation after Stroke
Published on: June 6, 2025
SIAXI: Placebo-controlled, randomized, double-blind study of incobotulinumtoxinA for sialorrhea
Wolfgang H Jost1, Andrzej Friedman2, Olaf Michel2
1From the Parkinson-Klinik Ortenau (W.H.J.), Wolfach, Germany; Department of Neurology (A.F.), Faculty of Health Science, Medical University of Warsaw, Poland; Department of Otorhinolaryngology (O.M.), University Hospital Brussels, Vrije Universiteit Brussel, Belgium; Neurological Outpatient Clinic for Parkinson's Disease and Deep Brain Stimulation (C.O.), Gera, Germany; Department of Neurological-Psychiatric Nursing (J.S.), Medical University of Gdansk; Neurology Department (J.S.), St. Adalbert Hospital, Gdansk; Department of Extrapyramidal Diseases (A. Bogucki), Medical University of Łódź; Department of Neurology and Stroke Unit (S.O.), Medical University of Silesia, Katowice; Department of Neurology (M.B.), Collegium Medicum, Jagiellonian University, Krakow, Poland; Department of Neurology (F.P.), Georgetown University Hospital, Washington, DC; Merz Pharmaceuticals GmbH (B.F.-B., J.C.), Frankfurt am Main, Germany; Complete Medical Communications (C.J.C.), Glasgow, UK; Department of Otolaryngology/Head and Neck Surgery (A. Blitzer), Columbia University College of Physicians and Surgeons, New York; Department of Neurology (A. Blitzer), Icahn School of Medicine at Mt. Sinai, New York; and NY Center for Voice and Swallowing Disorders (A. Blitzer), New York, NY. w.jost@parkinson-klinik.de.
Objective:
This pivotal phase III study, SIAXI, investigated the efficacy and safety of incobotulinumtoxinA for the treatment of chronic sialorrhea due to Parkinson disease (PD), atypical parkinsonism, stroke, or traumatic brain injury (TBI).
Methods:
Adult patients with PD (70.7%), atypical parkinsonism (8.7%), stroke (19.0%), or TBI (2.7%) were randomized (2:2:1) to double-blind treatment with placebo (n = 36), or total doses of incobotulinumtoxinA 75 U (n = 74) or 100 U (n = 74), in a single treatment cycle. The coprimary endpoints were change in unstimulated salivary flow rate from baseline to week 4, and patients' Global Impression of Change Scale score at week 4. Adverse events were recorded throughout.
Results:
A total of 184 patients were randomized. Both incobotulinumtoxinA dose groups showed reductions in mean unstimulated salivary flow rate at week 4, with a significant difference vs placebo in the incobotulinumtoxinA 100 U group (p = 0.004). Patients' Global Impression of Change Scale scores also improved at week 4, with a significant difference vs placebo in the incobotulinumtoxinA 100 U group (p = 0.002). A lasting effect was observed at week 16 post injection. The most frequent treatment-related adverse events in the incobotulinumtoxinA 75 U and 100 U groups were dry mouth (5.4% and 2.7% of patients) and dysphagia (2.7% and 0.0% of patients).
Conclusions:
IncobotulinumtoxinA 100 U is an effective and well-tolerated treatment of chronic sialorrhea in adults.
Clinicaltrialsgov Identifier:
NCT02091739.
Classification Of Evidence:
This study provides Class I evidence that incobotulinumtoxinA reduces salivary flow rates in patients with chronic sialorrhea due to PD, atypical parkinsonism, stroke, or TBI.
More Related Videos
Related Concept Videos
02:07Blind Procedures
01:54The Placebo Effect
01:11Blinding
01:20Bioequivalence Experimental Study Designs: Completely Randomized and Randomized Block Designs
01:23Types of Biopharmaceutical Studies: Controlled and Non-Controlled Approaches
Non-controlled studies, commonly employed for initial exploration, lack a control group, rendering them susceptible to biases and external influences. In contrast,...
01:04Random Error