Observational Study of VYKAT™ XR in Patients With Prader-Willi Syndrome

An Observational Study of VYKAT™ XR (Diazoxide Choline Extended-Release Tablets) in Patients With Prader-Willi Syndrome (PWS)

Prospective observational study developed to generate more evidence of the safety profile, clinical characteristics and outcomes of patients with PWS treated with VYKAT XR.

Study Overview

• Status: Enrolling by invitation
• Conditions: Prader-Willi Syndrome
• Intervention / Treatment: Drug: VYKAT XR

Detailed Description

Patients with PWS at participating sites who are initiating treatment or have initiated treatment with VYKAT XR, including patients who were previously treated with DCCR in a prior clinical study, will be invited to participate. Data from treatment prior to enrollment either from clinical practice or from previous DCCR clinical trials may be collected retrospectively.

Clinical care will not be mandated by the protocol.

• Study Type: Observational
• Enrollment (Estimated): 200

Contacts and Locations

Study Locations

• United States
  • California
    • Los Angeles, California, United States, 90027
      • Children's Hospital Los Angeles
  • Georgia
    • Atlanta, Georgia, United States, 30322
      • Emory Children's Center
  • Illinois
    • Chicago, Illinois, United States, 60611
      • Northwestern University Feinberg School of Medicine
  • Indiana
    • Indianapolis, Indiana, United States, 46202
      • Indiana University
  • Michigan
    • Ann Arbor, Michigan, United States, 48109
      • University of Michigan Medical Center
    • Lansing, Michigan, United States, 48912
      • Sparrow Clinical Research Institute
  • Minnesota
    • Saint Paul, Minnesota, United States, 55102
      • Children's Minnesota
  • Missouri
    • Kansas City, Missouri, United States, 64111
      • Children's Mercy Hospital
  • New Jersey
    • Paterson, New Jersey, United States, 07503
      • Saint Josephs Health
  • New York
    • Valley Stream, New York, United States, 11580
      • Long Island Jewish Valley Stream
  • North Carolina
    • Chapel Hill, North Carolina, United States, 27514
      • UNC Hospitals
  • Oregon
    • Portland, Oregon, United States, 97227
      • Legacy Emanuel Medical Center
  • Tennessee
    • Nashville, Tennessee, United States, 37232
      • Vanderbilt University Medical Center
  • Texas
    • Dallas, Texas, United States, 75231
      • Children's Medical Center Dallas
  • Washington
    • Seattle, Washington, United States, 98105
      • Seattle Children's Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

This study will enroll patients with PWS who are currently receiving or initiating treatment with VYKAT XR.

Description

Inclusion Criteria:

• Patients currently receiving or initiating treatment with VYKAT XR, including patients who previously received DCCR or are transitioning from DCCR to VYKAT XR in the context of a prior DCCR clinical trial.
• Patients and/or caregivers must provide written informed consent.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Intervention / Treatment

Patients with PWS who are currently receiving or initiating treatment with VYKAT XR.; All patients with PWS at participating sites who are initiating treatment or have initiated treatment with VYKAT XR at the time of enrollment into this observational study, including patients who were previously treated with DCCR in a prior clinical study, will be invited to participate. Although the overall observational study is prospective, data from treatment prior to enrollment into the observational study, either from clinical practice or from DCCR clinical trials, may be collected retrospectively.

Drug: VYKAT XR; All prospective treatment in this protocol will be commercial VYKAT XR prescribed to patients by their physicians in addition to their standard of care; patients will not receive experimental intervention or treatment from the Sponsor as part of their participation in this study.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Assess safety profile of patients with PWS treated with VYKAT XR.	The safety profile will be based on adverse events, including nonserious adverse events, serious adverse events, and adverse events leading to discontinuation of VYKAT XR.	Adverse events for each patient will be collected from the time of first dose on VYKAT XR until the last contact with the patient.

Collaborators and Investigators

• Sponsor: Soleno Therapeutics, Inc.

Study record dates

Study Major Dates

• Study Start (Actual): November 26, 2025
• Primary Completion (Estimated): March 1, 2028
• Study Completion (Estimated): March 2, 2028

Study Registration Dates

• First Submitted: February 9, 2026
• First Submitted That Met QC Criteria: March 1, 2026
• First Posted (Actual): March 5, 2026

Study Record Updates

• Last Update Posted (Actual): May 19, 2026
• Last Update Submitted That Met QC Criteria: May 15, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Prader-Willi Syndrome; PWS
• Additional Relevant MeSH Terms: Imprinting Disorders; Neurologic Manifestations; Nervous System Diseases; Nutrition Disorders; Genetic Diseases, Inborn; Overnutrition; Neurobehavioral Manifestations; Congenital Abnormalities; Abnormalities, Multiple; Overweight; Intellectual Disability; Obesity; Chromosome Disorders; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Nutritional and Metabolic Diseases; Prader-Willi Syndrome
• Other Study ID Numbers: C623

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: Yes