A Study to Evaluate the Safety and Efficacy of PTC518 in Participants With Huntington’s Disease (HD)

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

PTC Identifier:
PTC518-CNS-002-HD
ClinicalTrials.gov Identifier:
NCT05358717
EudraCT Identifier:
2021-003852-18
Not Recruiting

Trial Purpose

Age
25+ years
Sex
Both (Female and Male)
Healthy Volunteers
No

Key Participation Requirements

Inclusion Criteria:

  • Genetically confirmed HD diagnosis with a cytosine-adenine-guanine (CAG) repeat length from 40 to 50, inclusive
  • Eligibility for HD-ISS Stage 2 Group (Parts A, B, and C):

Exclusion Criteria:

  • Receipt of an experimental agent within 90 days or 5 half-lives prior to Screening or anytime over the duration of this study, ribonucleic acid (RNA)- or deoxyribonucleic acid (DNA)-targeted HD-specific investigational agents such as antisense oligonucleotides, cell transplantation, or any other experimental brain surgery
  • Any history of gene therapy exposure for the treatment of HD

Trial Summary

Total Participants

This is the number of individuals who are taking part in the trial.

Total Participants
252

Trial Dates

These are the start and end dates for the trial. Note that future dates are estimates that may be updated before or during the trial.

Trial Dates
Apr 2022 - Feb 2025

Phase

These are the different steps that a treatment goes through during clinical development before it is approved for use.

Phase
Phase 2

Placebo Controlled

In this type of study, some participants receive a “placebo,” which looks like the study treatment, but does not actually contain the active treatment.

Placebo Controlled
Yes

Product

This is any type of drug, device, or other treatment that is being studied in the trial.

Product
N/A

Accepts Healthy Volunteers

Healthy volunteers are individuals who participate in the trial and do not have that specific disease or condition.

Accepts Healthy Volunteers
No
Discuss with the trial center for details

Trial Design

Trial Type

This is the general nature of the study.

Trial Type
Interventional

Interventional

Participants in these studies are subject to an intervention by researchers. These trials are used to understand the effects of a particular intervention.

Discuss with the trial center for details

Blinding

Study participants know which treatments they might get if they join the trial, however during a trial they may not be informed which treatment they are actually taking. The act of not disclosing this information to the participant is known as “blinding.”

Blinding
N/A
Discuss with the trial center for details

Intervention Type

This is a medicine, device, or other type of treatment that is being studied or is already approved for use. Interventions can also include behavior changes, like diet and exercise.

Intervention Type
Drug

Allocation

This determines how study participants are assigned their treatment.

Allocation
Randomized

Randomized

This means participants are randomly assigned to the different arms of the study.

Trial Purpose

This is the rationale behind why the clinical trial is being performed.

Trial Purpose
Treatment

Trial Arms

These are the groups of participants in a clinical study. Each different “arm” is assigned a different treatment to use. Different types of trial arms in studies can include:

Trial Arms
Experimental

Experimental arm

Experimental arm: The group assigned to use the study treatment

Primary Outcome

Primary Outcome

This is the most important measurement of the study and is used to help researchers evaluate the effect of a treatment.

Number of Participants With Adverse Events (AEs)

Timeframe: Baseline up to Month 18

Change From Baseline in Blood Total Huntingtin Protein (tHTT) at Month 3

Timeframe: Baseline, Month 3

Secondary Outcome

Secondary Outcome

This measurement is a secondary measurement and is still important in helping researchers evaluate the effect of a treatment.

Change From Baseline in Caudate Volume as Assessed Via Volumetric Magnetic Resonance Imaging (vMRI) at Month 12

Timeframe: Baseline, Month 12

Change From Baseline in Composite Unified Huntington’s Disease Rating Scale (cUHDRS) Scores at Month 12

Timeframe: Baseline, Month 12

Change From Baseline in Blood tHTT Protein at Month 12

Timeframe: Baseline, Month 12

Change From Baseline in Cerebrospinal Fluid (CSF) Mutant Huntingtin Protein (mHTT) at Month 12

Timeframe: Baseline, Month 12

Change From Baseline in Blood mHTT Protein at Month 12

Timeframe: Baseline, Month 12

Contact Information

Location
Status
Location
University of California, San Diego
La Jolla, CA, United States, 92037
Status
Active, not recruiting
Location
Georgetown University
Washington, DC, United States, 20007
Status
Withdrawn
Location
Vanderbilt University Medical Center
Nashville, TN, United States, 37212
Status
Active, not recruiting
Location
University of Alabama at Birmingham
Birmingham, AL, United States, 35294
Status
Withdrawn
Location
The University of Texas Health Science Center at Houston; McGovern Medical School
Houston, Texas, United States, 77030
Status
Active, not recruiting
Location
Columbia University, G.H. Sergievsky Center
New York, NY, United States, 10032
Status
Withdrawn