Study to Assess PXL065 in Subjects With Adrenomyeloneuropathy (AMN) Form of X-linked Adrenoleukodystrophy (X-ALD or ALD)

An Open-label Phase 2a Study to Assess the Pharmacokinetics and Pharmacodynamic of PXL065 Parameters After 12 Weeks of Treatment in Male Subjects With Adrenomyeloneuropathy (AMN) Form of X-linked Adrenoleukodystrophy (X-ALD or ALD)

A randomized open-label Phase 2a study to assess the pharmacokinetics and pharmacodynamic parameters of PXL065 after 12 weeks of treatment in male subjects with adrenomyeloneuropathy (AMN).

A randomized open-label Phase 2a study to assess the pharmacokinetics and pharmacodynamic parameters of PXL065 after 12 weeks of treatment in male subjects with adrenomyeloneuropathy (AMN).

There will be a total of 3 study periods.

• Screening period of a maximum of 4 weeks prior to the open-label Treatment Period (Baseline Visit - V2). This period can be exceptionally extended for 2 weeks
• Open-label Treatment Period of 12 weeks
• Follow-up Period of 2 weeks after the last intake of the treatment (V5-End of Treatment Visit (EoT)).

During the treatment period, very long chain fatty acids (VLCFA) will be assessed every 4 weeks, to evaluate the kinetics of the PXL065 effect. Neurofilament light (NfL) will be assessed after 8 and 12 weeks of treatment, and other exploratory biomarkers after 12 weeks of treatment. A follow up period will allow continued monitoring the subjects' safety and evaluation of the kinetics of the 2 main biomarkers (VLCFA and NfL) at 2 weeks after the last intake of the treatment.

Inclusion Criteria:

• Male subjects with either a confirmed diagnosis of AMN by genetic testing (mutation in the ATP binding cassette subfamily D (ABCD1 gene)) or a family history of X-linked adrenoleukodystrophy (ALD) together with an elevation in VLCFA obtained from overnight fasting plasma sample at Screening Visit (V1).
• Age: ≥ 18 to ≤ 65 years at informed consent signature.
• Normal brain magnetic resonance imaging (MRI) or brain MRI showing non-specific abnormalities that can be observed in AMN subjects without signs of cerebral form of ALD (C-ALD). MRI must be performed within 6 months prior to V2. If there is no available brain MRI within this period, a brain MRI must be performed before V2

Exclusion Criteria:

• Any progressive neurological disease other than AMN.
• Arrested or progressing C-ALD as defined by cerebral lesions (except for non-specific abnormalities that can be observed in AMN subjects).
• Prior receipt of an allogeneic hematopoietic stem cell transplant or gene therapy