Exploring how botulinum toxin affects arm tremors in dystonia patients

Factors Determining the Efficacy of Botulinum Toxin for Arm Tremor in Dystonia: An Exploratory Study

PHASE4 · Radboud University Medical Center · NCT06411028

This study is testing if botulinum toxin injections can help reduce arm tremors in people with dystonia and aims to find out which patients might benefit the most.

Quick facts

PhasePHASE4
Study typeInterventional
Enrollment60 (estimated)
Ages18 Years and up
SexAll
SponsorRadboud University Medical Center (other)
Locations3 sites (Nijmegen, Gelderland and 2 other locations)
Trial IDNCT06411028 on ClinicalTrials.gov

What this trial studies

This clinical trial investigates the effectiveness of botulinum neurotoxin (BoNT) injections for treating arm tremors in patients with dystonic tremor syndrome (DTS). The study aims to identify which clinical and pathophysiological characteristics are associated with better outcomes from BoNT treatment. Participants will undergo various assessments, including clinical evaluations, electromyography, muscle ultrasound, and functional MRI, before and after receiving BoNT injections over a period of eight months. The goal is to personalize treatment approaches based on individual patient characteristics.

Who should consider this trial

Good fit: Ideal candidates for this study are adults aged 18 and older with a clinical diagnosis of dystonic tremor or tremor associated with dystonia in one or both upper extremities who are starting BoNT treatment.

Not a fit: Patients with acquired causes of dystonic tremor or those who have had prior extensive botulinum toxin treatment may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to more effective and personalized treatment options for patients suffering from arm tremors due to dystonia.

How similar studies have performed: Other studies have shown varying success with botulinum toxin for treating tremors, but this specific approach focusing on personalized treatment based on individual characteristics is relatively novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Clinical diagnosis of dystonic tremor or tremor associated with dystonia according to the 2018 consensus statement on the classification of tremors
* Tremor of one or both upper extremities
* Starting botulinum toxin injections as part of normal clinical practice
* Age ≥ 18 years

Exclusion Criteria:

* Acquired aetiology of dystonic tremor syndrome
* Previous botulinum toxin treatment of the to be treated upper extremity for ≥ 4 consecutive sessions
* In case of previous botulinum toxin treatment of the to be treated upper extremity for ≤3 consecutive sessions: the last botulinum toxin injections ≤ 6 months before study enrolment
* Unstable dose medications for dystonia and tremor ≤ 1 month before study enrolment
* Deep brain stimulation implantation ≤ 6 months before study enrolment
* Unstable deep brain stimulation variables ≤ 1 month before study enrolment
* Comorbidity interfering with study participation
* Known hypersensitivity for components of Dysport
* Infection at the upper extremity
* Pregnancy, trying to conceive and breastfeeding
* Insufficient knowledge of the Dutch or English language

Exclusion criteria for MRI scanning:

* Contraindications for MRI (e.g. previous brain surgery, claustrophobia, active implant, epilepsy, metal objects in the upper body that are incompatible with MRI)
* Moderate to severe head tremor while lying supine (to avoid artefacts caused by extensive head motion during scanning).
* Inability to provoke postural tremor while lying supine.

Where this trial is running

Nijmegen, Gelderland and 2 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Dystonic Tremor Syndrome, Botulinum neurotoxin, Botulinum toxin, Dystonia, Dystonic tremor syndrome, Dystonic tremor, Tremor associated with dystonia, Upper extremity

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.