An Extension Study to Evaluate the Long-Term Safety and Efficacy of PTC518 in Participants With Huntington's Disease (HD)

Huntington Disease Clinical Trial

Official title:

A Phase 2b, Double-Blind, Randomized Extension Study to Evaluate the Long-Term Safety and Efficacy of PTC518 in Participants With Huntington's Disease

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT06254482
• Other study ID #: PTC518-CNS-004-HD
• Secondary ID: 2023-504628-24-0
• Status: Recruiting
• Phase: Phase 2
• Start date: August 25, 2023
• Est. completion date: July 20, 2027

Study information

• Verified date: May 2024
• Source: PTC Therapeutics
• Contact: Patient Advocacy
• Phone: 1-866-562-4620
• Email: medinfo[@]ptcbio.com
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The primary goal of this study is to evaluate the long-term safety and pharmacodynamic effects of PTC518 in participants with HD.

Description:

Participants who completed the Treatment Period in the parent Phase 2a Study PTC518-CNS-002-HD (NCT05358717), fulfilled the enrollment criteria, and chose to enroll in this extension study will undergo baseline evaluations and be assessed for 30 additional months.

All participants will receive active PTC518 in this extension study. Participants who received PTC518 in the parent Study PTC518-CNS-002-HD will continue at the same dose level they received in that study in a blinded fashion (5, 10, or 20 milligrams [mg]). Participants who received placebo in the parent Study PTC518-CNS-002-HD will be allocated to a PTC518 dose level according to the same dosing group in which they were previously randomized (5, 10, or 20 mg). The 20 mg dosing arm will be open for randomization only if and when the Data Safety and Monitoring Board from the parent Study PTC518-CNS-002-HD recommends initiating this dosing level based on an unblinded review of safety data from that study.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 250
• Est. completion date: July 20, 2027
• Est. primary completion date: June 30, 2027
• Accepts healthy volunteers: No
• Gender: All
• Age group: 25 Years and older

Eligibility

Inclusion Criteria:

• Participant who has completed the Treatment Period in Study PTC518-CNS-002-HD.

Exclusion Criteria:

• Participants who have not previously completed the Treatment Period in Study PTC518-CNS-002-HD.

Note: Other inclusion and exclusion criteria may apply.

Related Conditions & MeSH terms

• Huntington Disease

Intervention

Drug:
• PTC518
PTC518 will be administered per dose and schedule specified in the arm.

Locations

Country	Name	City	State
Australia	Monash Health	Clayton
Australia	Westmead Hospital	Westmead
Austria	Medical University Innsbruck	Innsbruck
Canada	The Ottawa Hospital, Parkinson's and Movement Disorders Clinic	Ottawa
France	Centre Hospitalier Universitaire d'Angers	Angers
France	Hôpital Universitaire de Marseille Hôpital de la Timone	Marseille
France	Brain and Spine institute Paris	Paris
Germany	Charite University Medicine Berlin	Berlin
Germany	Ruhr-Univ. Bochum St. Joseph-Hospital	Bochum
Germany	George-Huntington-Institut	Münster
Germany	Ulm University, UKU, Dep. of Neurology	Ulm
Italy	Irccs Istituto Delle Scienze Neurologiche Di Bologna Uoc Clinica Neurologica	Bologna
Italy	IRCCS Carlo Besta Neurological Institutte	Milan
Italy	IRCCS Casa Sollievo della Sofferenza Research Hospital	San Giovanni Rotondo
Netherlands	Leiden University Medical Center	Leiden
New Zealand	University of Otago, New Zealand Brain Research Institute	Christchurch
Spain	Hospital Universitario Cruces	Barakaldo
Spain	Hospital de la Santa Creu I Sant Pau	Barcelona
Spain	Hospital Universitario Burgos	Burgos
Spain	Hospital Ramón y Cajal	Madrid
United Kingdom	The Barbery National Centre for Mental Health	Birmingham
United Kingdom	University Hospital of Wales	Cardiff
United Kingdom	UCL Queen Square Institute of Neurology National Hospital for Neurology and Neurosurgery	London
United Kingdom	Manchester University NHS Foundation Trust	Manchester

Sponsors (1)

Lead Sponsor	Collaborator
PTC Therapeutics

Countries where clinical trial is conducted

Australia,  Austria,  Canada,  France,  Germany,  Italy,  Netherlands,  New Zealand,  Spain,  United Kingdom, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Number of Participants With Treatment-emergent Adverse Events (TEAEs)		Baseline up to Month 30
Primary	Blood Total Huntingtin Protein (tHTT) Levels		Baseline up to Month 28
Secondary	Change From Baseline in Caudate Volume as Assessed Via Volumetric Magnetic Resonance Imaging (vMRI) at Month 24		Baseline, Month 24
Secondary	Change From Baseline in Composite Unified Huntington's Disease Rating Scale (cUHDRS) Scores at Month 24		Baseline, Month 24
Secondary	Cerebrospinal Fluid (CSF) Mutant Huntingtin Protein (mHTT) Levels		Baseline up to Month 24
Secondary	Blood mHTT Protein Levels		Baseline up to Month 28