Myobloc Atrophy Study

Botulinum toxin has long been used as a clinical application for the treatment of overactive
skeletal and smooth muscles, i.e. spasticity. The benefits of botulinum therapy are
indisputable, however, muscle atrophy is one main adverse effect that may hinder a patient's
strength and decrease the ability for the practitioner to accurately administer botulinum
toxin to a specific muscle group. This, in turn may cause unintentional weakness of adjacent
muscle groups through inaccurate targeting or diffusion of botulinum toxin. Currently, only
two serotypes (abbreviated to BTX-A (BOTOX, XEOMIN and DYSPORT) and BTX-B (MYOBLOC),
respectively) are used in clinical practice for spasticity. Research has shown that both
BTX-A and BTX-B are efficacious in the treatment of spasticity. However, there is no
documented literature evaluating if there is a statistically significant difference in the
degree of muscle atrophy using BTX-A versus BTX-B.

Inclusion Criteria:

- Men and women aged 18 or older with spasticity secondary to either a disorder or
trauma, such as a spinal cord injury (SCI), a brain injury, a tumor, a stroke,
multiple sclerosis (MS), or a peripheral nerve injury.

- Participants must have the ability to provide written consent to participate in the
study.

Exclusion Criteria:

- Patients who have received BTX-A or BTX-B in the past in the skeletal muscle group
under investigation or patients who have had an allergic response to BTX-A or BTX-B
in the past.

- Diagnosis of Myasthenia gravis, Eaton-Lambert Syndrome, or Amyotrophic Lateral
Sclerosis. Females who are pregnant or breastfeeding. Subjects taking Aminoglycosides
or other agents interfering with neuromuscular function.