(ASPEN-1) A Phase 3, Randomized, Double-Blind, Placebo-Controlled, Parallel Group, Multi-Center Trial to Evaluate the Efficacy and Safety of a Single Treatment of DaxibotulinumtoxinA for Injection in Adults with Isolated Cervical Dystonia


Researchers want to find out if daxibotulinumtoxinA for injection, a new investigational study drug, is safe and effective for use in adults with isolated cervical dystonia (CD) and if the effects last longer than the standard toxin treatment. An “investigational drug” is a drug that is being tested, and is one that has not been approved for sale by the U.S. Food and Drug Administration (FDA).


  • If enrolled in the study, you will receive one treatment of either the investigational drug or the placebo.
  • The study is divided into 3 time periods: (1) Screening period (up to 3 weeks), (2) Treatment period (1 day), and Follow-up period (up to 36 weeks)
  • You will receive all study-related procedures and the investigational drug at no cost.


  • 18-80 years of age
  • Diagnosed with isolated cervical dystonia

For additional study information and eligibility criteria, please contact Amanda Fessenden:

Study Information Flyer


18 to 65
65 and over



Monetary compensation


Can be done from home



Dystonia, Neurology

Principal Investigator

Irene Malaty, MD



Contact Information


(352) 733-2431

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