Research Study for Single-Patient Treatment of Cree Leukoencephalopathy/Vanishing White Matter Disease

NCT07272525 | Active Not Recruiting Early Phase 1 FDA Drug

• 1 other identifier: 2025-10780 (CLE-ABBV-CLS-7262)
• Study Type: interventional
• Target: 1
• Locations: 1 country
• Sites: 1

Brief Summary

Cree Leukoencephalopathy (CLE) is a rare and fatal neurodegenerative disorder predominantly affecting the Cree population in Northern Quebec. Characterized by progressive white matter degeneration, this condition leads to severe neurological impairment and decline, leading to premature death. Despite its significant impact on the affected population, there are currently no effective treatments for CLE. CLE is caused by a single founder pathogenic variant in the EIF2B5 gene and is therefore allelic to VWM. Fosigotifator (FGT, ABBV-CLS-7262) has been developed and its safety and efficacy are currently being studied in a multi-center Phase 1b/2 clinical trial for Vanishing White Matter (VWM) by Calico in collaboration with AbbVie. This study aims to provide under compassionate use program access to an investigational drug (FGT) for a patient diagnosed with CLE/VWM disease which has no treatment options currently available. The study will also evaluate the risk/benefit of FGT in slowing or halting the progression of white matter degeneration in a patient with CLE. By targeting the underlying pathophysiological mechanisms of white matter damage, FGT is expected to alleviate neurological symptoms and improve the quality of life for the patient. The outcomes of this study could provide critical insights into the disease's management and pave the way for the development of targeted therapies, ultimately offering hope to a population with limited treatment options.

Conditions

Cree Leukoencephalopathy; Vanishing White Matter

Outcome Measures

Primary Outcomes (1)

• Patient survival or need for continuous ventilatory support at 2 years

  Patient survival (yes/no) or need for continuous ventilatory support (yes/no) at 2 years

  3 years

Study Arms (1)

N=1 trial

EXPERIMENTAL

N=1 trial

Drug: Fosigotifator (FGT/ABBV-CLS-7262)

Interventions

Fosigotifator (FGT/ABBV-CLS-7262) DRUG

This study aims to provide under compassionate use program access to an investigational drug (FGT) for a patient diagnosed with Cree Leukoencephalopathy (CLE)/Vanishing White Matter (VWM) which has no treatment options currently available. The study will also evaluate the risk/benefit of FGT in slowing or halting the progression of white matter degeneration in a patient with CLE. By targeting the underlying pathophysiological mechanisms of white matter damage, FGT is expected to alleviate neurological symptoms and improve the quality of life for the patient. The outcomes of this study could provide critical insights into the disease's management and pave the way for the development of targeted therapies, ultimately offering hope to a population with limited treatment options.

N=1 trial

Eligibility Criteria

• Age: 4 Months+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

• The patient meets the following criteria:
• Molecularly confirmed diagnosis of CLE
• Pre-symptomatic or early symptomatic patient
• Signed informed consent from the Legal Guardians/caregivers (parents)

You may not qualify if:

• N/A

Sponsors & Collaborators

• McGill University Health Centre/Research Institute of the McGill University Health Centre: lead

Study Sites (1)

McGill University Health Centre

Montreal, Quebec, H4A3J1, Canada

Location

MeSH Terms

Conditions

Leukoencephalopathies

Condition Hierarchy (Ancestors)

Brain Diseases; Central Nervous System Diseases; Nervous System Diseases

Study Design

• Study Type: interventional
• Phase: early phase 1
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: MD, MSc, FRCPc

Study Record Dates

• First Submitted: October 11, 2024
• First Posted: December 9, 2025
• Study Start: November 14, 2024
• Primary Completion (Estimated): November 30, 2027
• Study Completion (Estimated): December 31, 2027
• Last Updated: December 30, 2025

Record last verified: 2025-12

Locations

CA (1)