The purpose of this project is to study the efficacy of three candidate molecules (Xenbilox, Tahor and Resveratrol) in order to decrease the production of oxysterols by reducing the synthesis of cholesterol and/or regulate the production of bile acids and/or enabling neuroprotective action within the motor neuron.

The primary objective of the study is:

- decrease the accumulation of metabolites which can have a negative impact on neurological and systemic function of patients with SPG5.

The secondary objectives of the study are:

• confirm the clinical and biological tolerance of the different candidate molecules under study
• improve the serum bile acid profile of patients with SPG5

Inclusion Criteria:

• patients that have confirmed through genetic testing their status as carriers of 2 mutations in the CYP7B1 gene
• age ≥ 18 years
• patients that have signed the informed consent form
• presence of health care coverage

Exclusion Criteria:

• known hypersensitvity to chenodeoxycholic acid, atorvastatin, resveratrol or to any of their byproducts
• cholesterol lowering medications other than the study treatment
• hepatic failure with transaminases >3 times the normal level
• progressive biliary pathology
• chronic diarrhea
• serious mental illness
• significant comorbid neurological disorder
• incapacity to understand information about the protocol
• unwilling or unable to participate in any part of the study
• participation in another clinical trial during the study period
• person deprived of liberty by judicial or administrative decision
• adult subject under legal protection or unable to consent
• pregnant or breastfeeding women
• lack of health care coverage
• absence of a signed informed consent form