X-linked Adrenoleukodystrophy

This is a Phase I/II clinical trial of gene therapy for treating X-linked adrenoleukodystrophy using a high-safety, high-efficiency, self-inactivating lentiviral vector (LV) TYF-ABCD1 to functionally correct the defective gene. The objectives are to evaluate the safety and efficacy of the intrathecal and intravenous lentiviral gene transfer clinical protocol.

X-linked adrenoleukodystrophy (X-ALD) is a hereditary white matter disorder caused by mutations in the ABCD1 gene leading to disturbances in the metabolism of fatty acids. This results in an accumulation of very long chain fatty acids (VLCFA) in the cells of the body causing damage to the central nervous system (white matter of the brain and spinal cord). The most common adult-onset X-ALD phenotype is adrenomyeloneuropathy (AMN), a slowly progressive myelopathic variant with demyelination of the long tracts in the spinal cord, clinically manifested as slowly progressive spastic paraparesis, sensory ataxia, bladder and sexual dysfunction. Although this rare disease is inherited X-linked, previous research revealed that up to 80% of heterozygous women develop AMN symptoms during their lifetime. The primary objectives of this study are 1) to assess the prevalence of symptomatic courses in female carriers of X-ALD and 2) to determine the impact of AMN symptoms on the quality of life of affected women in various areas (including everyday life, work, social network, sleep quality, sexuality, mood). Participants are asked to fill in self-report questionnaires, which are available in English, German, French, Spanish, and Italian, and are provided electronically on the online platform Leuconnect (https://www.leuconnect.com) launched by European Leukodystrophies Association (ELA) international (https://elainternational.eu/).

The Myelin Disorders Biorepository Project (MDBP) seeks to collect and analyze clinical data and biological samples from leukodystrophy patients worldwide to support ongoing and future research projects. The MDBP is one of the world's largest leukodystrophy biorepositories, having enrolled nearly 2,000 affected individuals since it was launched over a decade ago. Researchers working in the biorepository hope to use these materials to uncover new genetic etiologies for various leukodystrophies, develop biomarkers for use in future clinical trials, and better understand the natural history of these disorders. The knowledge gained from these efforts may help improve the diagnostic tools and treatment options available to patients in the future.

Observational, single-site prospective and minimally interventional study in women with X-linked adrenoleukodystrophy (ALD), conducted in France.

This study is a observational study conducted through recruiting X-linked adrenoleukodystrophy (X-ALD) patients, to build a comprehensive evaluation and long-term follow-up platform for X-ALD patients, and to provide a theoretical basis for the treatment and management of X-ALD patients.

CALD is an inflammatory demyelinating disease that causes severe motor and cognitive deficit leading to rapid death. Hematopoietic stem cell transplantation (HSCT) can halt neuroinflammation in CALD through the replacement of microglia (i.e., brain immune system) but only if performed during its early phase. Using standard brain MRI, it is estimated that only 30% of adult CALD patients are identified. Complex and lengthy clinical evaluations together with MRI reading from experts improve CALD detection but are not available in routine clinical practice. Diffusion tensor imaging is a quantitative microstructural technique that can identify neuroinflammation at a very early stage. Still, its implementation in clinical practice has been very limited due to high inter-center measurements variability and bias due to data quality issues. The approach we will use solves these problems by introducing an automatic calibration and standardization with systematic quality control enabling the use of all MRI scanners in clinical settings. The innovative aspect of this project lies on the validation of an expert-independent prognosis biomarker able to specifically identify patients at high-risk to convert to CALD so that treatment can be initiated at the early stage of neuroinflammation. We aim to demonstrate that this tool has at least a 2-fold sensitivity compared to the current standard of care.