Not Actual Patient

Are you caring for someone with Angelman syndrome?

Consider the REVEAL study, a clinical trial, investigating a potential treatment for people with Angelman syndrome.

REVEAL More

Are you caring for someone with Angelman syndrome?

Consider the REVEAL study, a clinical trial, investigating a potential treatment for people with Angelman syndrome.

REVEAL More

About Angelman Syndrome

Angelman syndrome is a rare genetic condition involving the loss of function of an important gene (UBE3A). This results in severe symptoms that may include:

  • Intellectual disability – difficulty learning
  • Limited/no speech
  • Seizure disorders (epilepsy)
  • Motor problems – difficulty walking, unstable gait, difficulty grasping
  • Behavioral problems - irritability, anxiety
  • Sleep disturbances
  • Gastrointestinal problems (constipation)

Symptoms of Angelman syndrome can prove to be a challenge that requires ongoing care throughout the individual’s entire lifespan.

About ION582

What is ION582?

ION582 is an investigational drug developed by Ionis being studied as a potential treatment for Angelman syndrome. Currently, there are no approved therapies that address the underlying cause of Angelman syndrome. However, certain therapies are used to treat some of the symptoms that people with Angelman syndrome experience, such as seizure and sleep medications. Speech therapy, occupational therapy, and physical therapy are also used to treat disease manifestations and improve quality of life in some people living with Angelman syndrome.

Will I receive ION582?

Participants will be randomly assigned to receive either 40mg of ION582, 80mg of ION582, or placebo during the 60-week double-blind (DB) placebo-controlled treatment period. Double-blind means that neither the patient, parent/Legally Authorized Representative/guardian, nor the study doctor will know which assignment the patient is randomized to.  This reduces bias in results by allowing researchers to distinguish between treatment effects related to ION582 versus placebo effects. In case of an emergency, however, the study doctor can find out quickly whether the study drug or placebo was given to the study participant.

All participants completing the DB treatment period will be eligible to transition into the long-term extension (LTE) treatment period, where they will receive nine (9) doses of ION582 over a period of 100 weeks (approximately 23 months). During the LTE, all participants will receive 40mg or 80mg of ION582.

What is an “investigational drug?”

“Investigational drug” means that ION582 is currently being tested and is not approved for sale by regulatory agencies like the U.S. Food and Drug Administration (FDA). Since ION582 is not approved by regulatory agencies, it is considered investigational and only allowed to be used in clinical studies like the REVEAL study. ION582 is currently being studied in a global Phase 1/2a study called HALOS in 55 people living with Angelman syndrome. The REVEAL study was designed based on data from HALOS.

What to expect during the study?

Participation in the REVEAL study lasts about four (4) years and involves the following:

  • Health questions
  • Physical and neurological examinations
  • Collection of vital signs (i.e., height, weight, blood pressure, heart rate, etc.)
  • Blood and urine tests
  • Electroencephalogram (EEG) - measures electrical activity of the brain using small stickers attached to the scalp
  • Electrocardiogram (ECG) - measures electrical activity of the heart
  • Various assessments and questionnaires to assess function and potential improvement
  • Lumbar puncture (medical procedure that involves inserting a needle into the lower back) with anesthesia and/or sedation
  • Intrathecal dosing every three (3) months

Participation in a clinical study is voluntary. The parent, guardian or legally authorized representative (LAR) may withdraw consent and remove the participant from the study at any time, for any reason.

Newly diagnosed?

Visit Angelman Syndrome Foundation’s page to learn more about navigating a recent diagnosis of Angelman syndrome.

Newly diagnosed?

Overview of clinical trials

Here are some common questions and answers about study participation.

Interested in the REVEAL study?

Contact a Study Clinic
This study is being conducted by Ionis Pharmaceuticals
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