Allogenic Adipose Tissue-derived Mesenchymal Stromal Cells for the Treatment of Primary Progressive Multiple Sclerosis

Percentage of patients experiencing at least one adverse effect (AE) due to ASC infusion qualified as CTCAE V5 grade ≥ 3 or qualified as "serious" AE using the MeDRA terminology, and occurring between the first infusion and the end of the follow-up. The severity of the AE and the causality of the ASC infusion will be validated by a DSMB

Number and description of AE (related to the experimental product) using MedDRA terminology and CTCAE V5 at each time point during the study

Percentage of patients with 3-months Confirmed Disability Progression (CDP) between W0 and W24-W48. Disability progression will be defined as an increase of 1pt Expanded Disability Status Scale (EDSS).

The Expanded Disability Status Scale (EDSS) is a method of quantifying disability in multiple sclerosis and monitoring changes in the level of disability over time. It is widely used in clinical trials and in the assessment of people with MS.

(Disability progression will be defined as an increase of 1.5 pt if baseline EDSS=0, 1pt EDSS (if baseline 1 ≤ EDSS<6), or an increase of 0.5pt if baseline EDSS is ≥ 6; confirmed at 6 months.) EDSS : Minimum Score 1, Maximum score 10, higher scores mean a worse outcome.

Mean change in EDSS score between W0 and W24-W48. Expanded Disability Status Scale (EDSS). The Expanded Disability Status Scale (EDSS) is a method of quantifying disability in multiple sclerosis and monitoring changes in the level of disability over time. It is widely used in clinical trials and in the assessment of people with MS.(Disability progression will be defined as an increase of 1.5 pt if baseline EDSS=0, 1pt EDSS (if baseline 1 ≤ EDSS<6), or an increase of 0.5pt if baseline EDSS is ≥ 6; confirmed at 6 months.) EDSS : Minimum Score 1, Maximum score 10, higher scores mean a worse outcome.

Percentage of patients with No Evidence of Progression (NEP): Evidence of Progression is defined by (1) EDSS progression confirmed at 3 months,

The Expanded Disability Status Scale (EDSS) is a method of quantifying disability in multiple sclerosis and monitoring changes in the level of disability over time. It is widely used in clinical trials and in the assessment of people with MS.

EDSS : Minimum Score 1, Maximum score 10, higher scores mean a worse outcome.

Percentage of patients with No Evidence of Progression (NEP): Evidence of Progression is defined by increase of at least 20% in the 9-Hole Peg Test -9HPT.

9HPT Nine-Hole Peg Test It is a quantitative measure of hand function and is tested with the nine-hole peg test. The patient is instructed to arrange pegs into nine holes in a board by both dominant and non-dominant hands in two consecutive trials for each hand. The amount of time (in seconds) required to place and remove all nine pegs is recorded for each trial.

Percentage of patients with No Evidence of Progression (NEP): Evidence of Progression is defined by increase of at least 20% in the Timed-25 Foot Walk -T25W

T25W Timed 25-foot walk test (T25W) The timed 25-foot walk test (T25W) is a quantitative measure of ambulation. The T25W is a reliable test for patients with more severe gait impairment because it primarily assesses walking speed. The patient is instructed to walk a distance of 25 feet as quickly as possible. Both ends are marked with prominent signs. Note, if the patient requires his/her assistive device while walking. As the patient completes trail 1 he/she is instructed to walk back to the starting point. The time will be recorded in seconds in both trials. Time limit = 180 seconds (3 minutes). Discontinued = Patient is unable to complete a trial in 3 minutes or completes the first trial but cannot complete trial 2 after a 5-minute rest period.

Mean change in MSFC composite score ((include -T25W, -9HPT- and PASAT-3)

The Multiple Sclerosis Functional Composite (MSFC) was designed by "The National MS Society's Clinical Outcome Assessment Task" and is a standardized tool used to quantify the degree of disability in patients with multiple sclerosis (MS)

Change in the MusiQOL score

The MusiQoL is a specific questionnaire comprising 31 questions describing nine dimensions of quality of life (Appendix 1):

activities of daily living (eight items); psychological well-being (four); relationships with friends (four); symptoms (three); relationships with family (three); relationships with the health care system (three); emotional and sexual life (two); coping (two); rejection (two).

Each item is scored from 1 (never/not at all) to 5 (always/very much). Before calculating the score of the dimensions, the scores of negatively written items are reversed. The score of a dimension is obtained by averaging the scores of its constituent items. The dimension scores are then transformed linearly into scores ranging from 0 to 100 (100 being the maximum quality of life level). A global quality of life score is also available.

Immunophenotyping in cerebrospinal fluid (CSF) and in blood assessing immunological and biomarkers modifications (at Week 0, Week 4, Week 12, Week 16, Week 24, Week 28, Week 48) immunophenotyping evaluation by : CSF and blood immune cells phenotyping CSF and blood cytokines and chemokines dosage MS biomarkers levels in blood and CSF (including Nfl and GFAP)

Alloimmunization in blood (at Week 0, Week 4, Week 12, Week 16, Week 24, Week 28): Detection of donor specific anti-HLA antibodies in the blood

Mean number of Gadolinium-enhancing lesions on spinal cord and cerebral MRI (Between W0 and W24-W48 and between W24- W48)

Mean number of new T2 lesions on spinal cord and cerebral MRI (Between W0 and W24-W48 and between W24- W48)

Mean change in brain volume on cerebral MRI (Between W0 and W24-W48 and between W24- W48)

Mean change in spinal cord volume on spinal cord MRI (Between W0 and W24-W48 and between W24- W48)