A Clinical Evaluation of Non-Invasive Vagus Nerve Stimulation for Temper Outbursts in People With PWS

Inclusion Criteria:

1. Genetically proven diagnosis of PWS.

2. Age 10-40 years.

3. History in the last six months of an average of at least two temper outbursts perweek.

4. Able to comply with requirements of study and provide consent or assent; If consentis to be provided by the participant's guardian, same applies to the guardian.

5. Concomitant use of psychiatric medication is allowed; participant must be on astable dose 90 days prior to screening with no plans for dose modification duringthe course of the study.

6. Concomitant use of psychotherapy/counseling is allowed. Therapies for mental healthor behavior challenges, including applied behavior analysis (ABA) are also allowed;however, participant must be on a stable regimen 90 days prior to screening with noplans for modification during the course of the study.

7. Living with family or in another setting with family members or staff willing tosupport the participant and the required data collection.

8. Agree to share tVNS patient application compliance and daily temper outburst datawith the sponsor.

9. Access to cellular data or Wi-Fi.

10. Participant and caregiver speak American English as first language or are fluent inAmerican English.

Exclusion Criteria:

1. Positive pregnancy test at screening, baseline, or at any point in the study.

2. Evidence of active or recent unstable serious mental illness, including, psychosis,mania, severe depression, or suicidality.

3. Moved to present residential placement in last three months or less.

4. Likely move in residential placement during the course of the study.

5. Cardiac abnormalities including medically documented history of cardiac disease orcardiac arrhythmia, documented resting heart rate ≤ 50 beats per minute (BPM); orhistory of 2° type 2 or 3° heart block on electrocardiogram (ECG).

6. Evidence of clinically significant abnormalities of blood, liver, or kidney functionfrom clinical safety laboratory assessments as determined by the Site Investigator.

7. History of blood clot, pulmonary embolism, or deep vein thrombosis.

8. Prior diagnosis of epilepsy or currently active seizures.

9. Current enrollment in the active phase of different clinical trial or interventionalstudy.

10. Current use of hearing aids or implantable medical devices including implanted vagusnerve stimulation (iVNS) device, implanted cardiac pacemaker, implanted cardiacdefibrillator, cochlear implants, cerebral shunt or cardiac implantable electricaldevices.

11. Presence of dermal abnormalities at the stimulation site that would interfere withthe ability of the tVNS device to function properly.

12. Presence of an allergy to titanium, titanium-iridium, thermoplastic elastomers,perfluoroethylene propylene, or polyurethane elastomers, or components of /preservatives present in the device electrode cream (Ceteareth-20, Propylene Glycol,Bentonite, Polysorbate 20, Phenoxyethanol, Ethylhexylglycerin).

13. Severe, untreated sleep apnea, as self-reported by subject or caregiver or suspectedby Site Investigator.

14. Subject is, in the opinion of the Investigator, not suitable to participate in thestudy.