Open-Label Extension Study of DCCR in PWS Followed by Double-Blind, Placebo-Controlled, Randomized Withdrawal Period

Prader-Willi Syndrome Clinical Trial

Official title:

An Open-Label, Long-Term Safety and Efficacy Evaluation of Diazoxide Choline Extended-Release Tablets in Participants With Prader-Willi Syndrome With a Double-Blind, Placebo-Controlled, Randomized Withdrawal Period

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03714373
• Other study ID #: C602
• Status: Completed
• Phase: Phase 3
• Start date: October 1, 2018
• Est. completion date: August 17, 2023

Study information

• Verified date: April 2024
• Source: Soleno Therapeutics, Inc.
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

This is a multi-center, multi-period study with an open-label period followed by a double-blind, placebo-controlled, randomized withdrawal period evaluating the safety and efficacy of DCCR treatment.

Description:

115 PWS participants who completed clinical study C601 will be enrolled into the OLE Period. All participants in the Open Label Extension (OLE) Period will receive open-label DCCR. The actual number of participants eligible to enroll in the double-blind, placebo-controlled, randomized withdrawal (RW) period will be limited to those participants taking DCCR in the OLE Period at the time of the RW Period Visit 1 (Baseline/Randomization Visit).The treatment groups in the C602 RW Period are those participants randomized to receive DCCR and those participants randomized to receive Placebo. Participants will be randomized in a 1:1 ratio (DCCR:Placebo).

Recruitment information / eligibility

• Status: Completed
• Enrollment: 115
• Est. completion date: August 17, 2023
• Est. primary completion date: August 17, 2023
• Accepts healthy volunteers: No
• Gender: All
• Age group: 4 Years and older

Eligibility

OLE Period Key Inclusion Criteria:

• Successful completion of clinical study C601
• Provide voluntary, written informed consent (parent(s) / legal guardian(s) of patient); provide voluntary, written assent (subjects, as appropriate)

OLE Period Key Exclusion Criteria:

• Positive urine pregnancy test (in females of child-bearing potential) or females who are pregnant or breastfeeding, and/or plan to become pregnant or to breast-feed during or within 90 days after study participation
• Any new disease, condition, or circumstance which would prevent, in the opinion of the Investigator, the patient from completing all study visits and assessments required by the protocol (e.g., an anticipated change of care setting)

RW Period Key Inclusion Criteria:

• Provide voluntary, written informed consent (parent[s] / legal guardian[s] of participant); provide voluntary, written assent (participants, as appropriate); this includes consent for randomization and potential treatment with placebo for up to 16 weeks
• Currently participating in clinical study C602 and complete the OLE End of Treatment Visit procedures

RW Period Key Exclusion Criteria:

• Positive urine pregnancy test (in females of child-bearing potential)
• Females who are pregnant or breastfeeding, and/or plan to become pregnant or to breast-feed during or within 30 days after study participation

Related Conditions & MeSH terms

• Prader-Willi Syndrome
• Syndrome

Intervention

Drug:
• DCCR
Once daily oral administration of open-label DCCR tablet(s) during the OLE Period
• DCCR
Once daily oral administration of double-blind (DCCR) tablet(s) during the RW Period
• Placebo for DCCR
Once daily oral administration of double-blind (placebo for DCCR) tablet(s) during the RW Period

Locations

Country	Name	City	State
United Kingdom	Birmingham Women's and Children's Hospital	Birmingham
United Kingdom	Fulbourn Hospital	Cambridge
United Kingdom	The Queen Elizabeth University	Glasgow	Scottland
United Kingdom	Hull and East Yorkshire Hospitals NHS Trust	Hull	Yorkshire
United Kingdom	Aintree University Hospital NHS Foundation Trust	Liverpool
United Kingdom	Chelsea and Westminster Hospital	London
United Kingdom	Hammersmith Hospital	London
United Kingdom	Royal London Hospital	London
United States	Emory Children's Center	Atlanta	Georgia
United States	Children's Hospital Colorado	Aurora	Colorado
United States	National Institutes of Health Hatfield Clinical Research Center	Bethesda	Maryland
United States	Boston Children's Hospital	Boston	Massachusetts
United States	University Hospitals Cleveland Medical Center	Cleveland	Ohio
United States	The Research Institute at Nationwide Children's Hospital	Columbus	Ohio
United States	Research Institute of Dallas	Dallas	Texas
United States	University of Florida Gainesville	Gainesville	Florida
United States	Indiana University School of Medicine	Indianapolis	Indiana
United States	Kansas University Medical Center	Kansas City	Kansas
United States	Sparrow Clinical Research Institute	Lansing	Michigan
United States	NYU Winthrop Hospital	Mineola	New York
United States	Vanderbilt University	Nashville	Tennessee
United States	University of California, Irvine	Orange	California
United States	Stanford University	Palo Alto	California
United States	St. Joseph's University Medical Center	Paterson	New Jersey
United States	Children's Minnesota	Saint Paul	Minnesota
United States	University of Utah	Salt Lake City	Utah
United States	Rady Children's Hospital San Diego	San Diego	California
United States	Seattle Children's Hospital	Seattle	Washington

Sponsors (1)

Lead Sponsor	Collaborator
Soleno Therapeutics, Inc.

Countries where clinical trial is conducted

United States,  United Kingdom, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Assess the safety of DCCR by evaluating the incidence and severity of adverse events reported	Safety analyses will be conducted in all participants who receive at least one dose of DCCR. Adverse events will be described by type and level of severity.	Baseline to end of OLE (up to 4 years)
Primary	Change from RW Period Baseline in HQ-CT Total Score	Hyperphagia-related behaviors will be assessed by the hyperphagia questionnaire for clinical trials (HQ-CT), an instrument designed to measure symptoms of food related preoccupations and behaviors. The HQ-CT consists of nine items with responses ranging from 0-4 (best to worst). Scores from 9 items will be summed for a possible total score range of 0-36.	RW Period Baseline to Week 16
Secondary	Change from Baseline in HQ-CT Total Score	Hyperphagia-related behaviors will be assessed by the hyperphagia questionnaire for clinical trials (HQ-CT), an instrument designed to measure symptoms of food related preoccupations and behaviors. The HQ-CT consists of nine items with responses ranging from 0-4 (best to worst). Scores from 9 items will be summed for a possible total score range of 0-36.	Baseline to end of OLE (up to 4 years)
Secondary	Change in Body Fat Mass	Change in Body Fat Mass (kg) using DXA	Baseline to end of OLE (up to 4 years)
Secondary	Clinical Global Impression of Improvement (CGI-I)	CGI-I is a single statement designed to assess the Investigator's overall perception of change in the subject's condition across the course of the clinical trial. The Investigator provides a response to "Compared to the subject's condition at enrollment, the subject's condition is:" by rating the subject's behavior using a 7-point response scale (best to worst).	RW Period Week 16
Secondary	Clinical Global Impression of Severity (CGI-S)	The CGI-S is a single statement designed to assess the Investigator's overall perception of the severity of the participant's illness across the course of the clinical trial. The Investigator provides a response to "Considering your total clinical experience with this particular population, how ill is this participant at this time:" by rating the subject's behavior using a 7-point response scale (best to worst).	RW Period Week 16
Secondary	Assess the safety of DCCR by evaluating the incidence and severity of adverse events reported	Safety analyses will be conducted in all participants who receive at least one dose of randomized withdrawal study drug. Adverse events will be described by type and level of severity.	through the end of the RW Period, 16 weeks