Single Treatment of DaxibotulinumtoxinA for Injection in Adults With Isolated Cervical Dystonia (ASPEN-1)

Approximately 300 subjects, recruited from approximately 80 study centers in the United
States (US), Canada, and Europe will be randomized to DAXI for injection high dose, DAXI for
injection low dose, or placebo group, respectively. Subjects will be stratified by treatment
center and history of prior treatment with botulinum neurotoxin (BoNT).

Inclusion Criteria:

- Adults, 18 to 80 years of age

- Meets diagnostic criteria for isolated CD (idiopathic; dystonic symptoms localized to
the head, neck, shoulder areas) with at least moderate severity at Baseline (Day 1),
defined as a TWSTRS-total score of at least 20, with at least 15 on the
TWSTRS-Severity subscale, at least 3 on the TWSTRS-Disability subscale, and at least 1
on the TWSTRS-Pain subscale

Exclusion Criteria:

- Cervical dystonia attributable to an underlying etiology, (e.g., traumatic torticollis
or tardive torticollis)

- Predominant retrocollis or anterocollis CD

- Significant dystonia in other body areas, or is currently being treated with BoNT for
dystonia in areas other than those associated with isolated CD

- Severe dysphagia (Grade 3 or 4 on the Dysphagia Severity Scale) at Screening or
Baseline (prior to study treatment)

- Any neuromuscular neurological conditions that may place the subject at increased risk
of morbidity with exposure to BoNT, including peripheral motor neuropathic diseases
(e.g., amyotrophic lateral sclerosis and motor neuropathy, and neuromuscular
junctional disorders such as Lambert-Eaton syndrome and myasthenia gravis)

- Previous treatment with any BoNT product for any condition within the 14 weeks prior
to Screening

- Botulinum Neurotoxin Type A (BoNTA), except the investigational daxibotulinumtoxinA,
treatment-experienced subjects who had suboptimal or no treatment response to the most
recent BoNTA injection for CD, as determined by the investigator, or history of
primary or secondary non-response to BoNTA injections, known to have neutralizing
antibodies to BoNTA; or have a history of botulinum toxin type B (rimabotulinumtoxinB
[Myobloc/Neurobloc]) injection for CD due to non-response or suboptimal response to
BoNTA