Adrenoleukodystrophy (X-ALD) is the most common genetic disorder of the brain white matter with an incidence of 1:14,700 births. It is caused by mutations in the ABCD1 gene, which encodes a transporter of very long-chain fatty acids (VCLFA) into the peroxisome for degradation. As a consequence VLCFA accumulate in tissues and plasma being the pathognomonic biomarker for diagnosis. The excess of VLCFA produces mitochondrial ROS and oxidative damage, a major factor driving X-ALD pathogenesis. Other key dysregulated pathways are energy production, mitochondrial biogenesis and respiration, proteostasis, and ER stress. Current therapeutic options are unsatisfactory, restricted to bone marrow transplant and gene therapy, for which most patients do not qualify. The encouraging results of plasma exchange (PE) with albumin replacement for Alzheimer's Disease prompted us to start this study. Our rationale is the following: In plasma, VLCFA are transported by lipoproteins and albumin. Albumin is the major transporter of fatty acids (FA) to the brain. ABCD1 deficiency induces inflammation and increases blood-brain barrier leakage, which could facilitate increased permeability to albumin. We posit that replacement of albumin would lower VLCFA levels in plasma through peripheral sink mechanisms, diminishing the quantity of VLCFA reaching the brain, and would prevent lipid peroxidation. A pilot proof-of-concept study in 5 X-ALD patients will be carried out to replace endogenous albumin through PE applied, once a week the first month and monthly for 5 months. A 6 months follow-up after the end of the treatment will be carried out.

Inclusion Criteria:

1. Men of 18 to 65 years old, inclusive

2. Elevated plasma VLCFA and gene mutation identified

3. Clinical signs of AMN with at least pyramidal signs in the lower limbs and difficulties to run

4. Presence of motor deficit according to the EDSS scale

5. Ability to perform the 2MWT

6. Normal brain MRI or brain MRI showing the following abnormalities that can be observed in AMN patients without the cerebral form of X-ALD, obtained in the 6 months prior to screening:

   • abnormal hyperintensity of pyramidal tract fibers in the brain stem on FLAIR or T2 sequence
   • abnormal hyperintensity of pyramidal tract fibers in the internal capsules on FLAIR or T2 sequence
   • cerebellar atrophy
   • moderate cortical atrophy

Exclusion Criteria:

1. Any contraindication for plasma exchange due to behavioral disorders or abnormal coagulation parameters, such for example:

   • Hypocalcemia (Ca++ < 8.7 mg/dl)
   • Thrombocytopenia (< 100.000/µl)
   • Fibrinogen < 1.5 g/l
   • Prothrombin time (Quick) p< 60% versus control (INR > 1.5)
   • Beta-blocker treatment and bradycardia < 55/min
   • Treatment with ACIs (increased risk of allergic reactions)

2. Hemoglobin < 10 g/dl

3. Difficult venous access precluding plasma exchange

4. A history of frequent adverse reactions (serious or otherwise) to blood products

5. Hipersensibility to albumin o allergies to any of the components of Albunorm® 5%

6. Plasma creatine > 2 mg/dl

7. Uncontrolled high blood pressure (systolic blood pressure of 160 mmHg or higher and/or diastolic blood pressure of 100 mmHg or higher despite regular treatment during the last 3 months)

8. Liver cirrhosis or any liver problem with GPT > 2.5 x ULN, or bilirubin > 2 mg/dl

9. Heart diseases as evidenced by myocardial infarction, severe or unstable angina, or heart failure in the past 12 months

10. Gadolinium enhancement on T1 sequence of any abnormal hypersignal of white matter, including myelinated pyramidal tracts, visible at brain MRI on FLAIR sequences

11. Significant peripheral edema (2+ or more on the Assessment Chart for Pitting Edema) of the extremities of any etiology

12. Any evolutive malignancy during the last five years or any condition complicating adherence to the study protocol

13. Smokers (one pack/ day or more for at least 20 years), current or former

14. Any psychiatric disease

15. Present participation to another therapeutic clinical trial for X-ALD, or the receipt of any other investigational drug in the three months prior to the start of the study

16. Patients being treated with anticoagulants or antiplatelet therapy

17. Not easily contactable by the investigator in case of emergency or not capable to call the investigator