A Phase 2 interventional study of VGL101 in ALSP, sponsored by Vigil Neuroscience, Inc.. Terminated at 10 sites in 5 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-06-11.
Sponsored by Vigil Neuroscience, Inc. (part of Sanofi) · Phase 2, Interventional, and Treatment
This is a multicenter, open-label study to assess the safety and tolerability of iluzanebart (also referred to as VGL101) in subjects with documentation of a gene mutation in the CSF1R gene for the treatment of adult-onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP) and to evaluate the effects of iluzanebart on imaging and biomarkers of disease progression in subjects with ALSP. Participants will receive infusions of iluzanebart approximately every 4 weeks for 1 year. The study includes a 52-week, open-label Core Study, followed by a Long-Term Extension (LTE), which provides subjects who complete the original 52-week study (Core Study) with the option to continue treatment for up to an additional 2 years.
39 studies on the registry are indexed under Leukoencephalopathies; 16 are open to participants now.
Browse Leukoencephalopathies studies →Vigil Neuroscience, Inc. is the lead sponsor of 3 studies on the registry; none are open to participants now.
First submitted before Vigil Neuroscience, Inc. became part of Sanofi.
Counted across the registry records on this site, refreshed daily.
Key Inclusion Criteria:
Participants fulfill both (Parts A and B) of the following criteria:
The participant has more than 2 findings of clinical signs or symptoms in the following categories:
Key Exclusion Criteria:
Solution administered via Intravenous Infusion (IV)
Drug: VGL101
Solution administered via Intravenous Infusion (IV)
Core Study Adverse Events
To evaluate the safety and tolerability of iluzanebart for the treatment of adult-onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP) by adverse events in the Core Study
Time frame: Through Week 52
Long-Term Extension Adverse Events
To evaluate the safety and tolerability of iluzanebart for the treatment of ALSP by adverse events in the Long-Term Extension
Time frame: Week 52 through Week 148
To evaluate the effects of iluzanebart on brain volume loss on MRI in subjects with ALSP in the Core Study
Percentage of subjects with minimal radiological progression from Baseline to Week 52
Time frame: Baseline and Week 52
To assess the correlation between brain volume loss on MRI and clinical measures of disease progression in subjects with ALSP in the Core Study
* Correlation between brain volume loss and Montreal Cognitive Assessment (MoCA) changes from Baseline to Week 52 * Correlation between brain volume loss and Cortical basal ganglia functional scale (CBFS) changes from Baseline to Week 52
Time frame: Baseline and Week 52
To evaluate the effects of iluzanebart on clinical measures of disease progression in subjects with ALSP in the Core Study
* Percentage of subjects with minimal progression in the MoCA scale, from Baseline to Week 52 * Percentage of subjects with minimal progression in CBFS from Baseline to Week 52 * Percentage of subjects who did not worsen in the Clinical Global Impression - Change (CGI-C) scale at Week 52
Time frame: Baseline and Week 52
To evaluate the effects of iluzanebart on fluid biomarkers of neurodegeneration in subjects with ALSP in the Core Study
Change from Baseline to Week 52 in neurofilament light chain (NfL) in and blood
Time frame: Baseline and Week 52
To evaluate the pharmacokinetics of iluzanebart in subjects with ALSP in the Core Study
Serum and cerebrospinal fluid (CSF) concentrations of iluzanebart
Time frame: Through Week 52
To evaluate the effects of iluzanebart on brain volume loss on MRI in subjects with ALSP in the Long-Term Extension
Change from Baseline to Weeks 76, 100, 124, and 148 in brain volume loss
Time frame: Baseline and Weeks 76, 100, 124, and 148
To assess the correlation between brain volume loss on MRI and clinical measures of disease progression in subjects with ALSP in the Long-Term Extension
* Correlation between brain volume loss and MoCA changes from Baseline to Weeks 76, 100, 124, and 148 * Correlation between brain volume loss and CBFS changes from Baseline to Weeks 76, 100, 124, and 148
Time frame: Baseline and Weeks 76, 100, 124, and 148
To evaluate the effects of iluzanebart on clinical measures of disease progression in subjects with ALSP in the Long-Term Extension
* Change from baseline to Weeks 64, 76, 88, 100, 112, 124, 136, and 148 in the MoCA and CBFS * Mean CGI-C score at Weeks 64, 76, 88, 100, 112, 124, 136, and 148
Time frame: Baseline and Weeks 64, 76, 88, 100, 112, 124, 136, and 148
To evaluate the effects of iluzanebart on fluid biomarkers of neurodegeneration in subjects with ALSP in the Long-Term Extension
Change from Baseline to Weeks 76, 100, 124, and 148 in NfL in blood
Time frame: Baseline and Weeks 76, 100, 124, and 148
To evaluate the pharmacokinetics of iluzanebart in subjects with ALSP in the Long-Term Extension
Serum and CSF concentrations of iluzanebart
Time frame: Week 52 through Week 148
Plan to share: No
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This study is terminated, as verified in Jun 2025. You cannot join it, but the record below documents what was studied.
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