A Follow-up Phase IIa Study to Evaluate the Long-term Safety and Efficacy Profile of ABX464 Given at 50 mg Once Daily in Subjects With Moderate to Severe Active Ulcerative Colitis.
Phase: PHASE2
Conditions: Ulcerative Colitis
Sponsor: Abivax S.A.

 
 
 
 
 
 
 
 
 
 
CLINICAL STUDY PROTOCOL 
ABX464-102 
 
Sponsor: 
ABIVAX 
 
5, rue de la Baume 
 
75008 Paris 
 
FRANCE 
 
Investigational product: 
 
ABX464  
Product code: 
 
ABX464 
Therapeutic indication: 
 
A follow-up Phase IIa study to evaluate the long-term safety and efficacy profile 
of ABX464 given at 50 mg once daily in subjects with Moderate to Severe Active 
Ulcerative Colitis. 
EudraCT number: 
 
2017-003284-35 
Study code: 
 
 
ABX464-102 
 
Version number:  
 
7.0 
Release date: 
 
 
February 07th, 2022 
 
 
 
 
CONFIDENTIALITY STATEMENT 
Information and data contained herein are proprietary and confidential. 
This information should not be disclosed to any third party without the prior written consent of ABIVAX 
 
 

ABIVAX 
Clinical Study Protocol 
Study code: ABX464-102 
 February 7th, 2022 
 
 
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CLINICAL STUDY PROTOCOL 
Study code 
ABX464-102 
Investigational product code 
ABX464 
EudraCT number 
2017-003284-35 
Detailed Title 
A follow-up Phase IIa study to evaluate the long-term safety and efficacy profile 
of ABX464 given at 50 mg once daily in subjects with Moderate to Severe Active 
Ulcerative Colitis. 
Study Phase 
Phase IIa 
Coordinating Investigator 
Prof. Severine Vermeire 
University Hospitals Leuven - campus Gasthuisberg 
Gastroenterology 
UZ Herestraat 49 - box 7003 08 
3000 Leuven 
Belgium 
Sponsor 
ABIVAX 
5 rue de la Baume 
75008 Paris 
Tel: +33 (0) 1 53 83 08 41 
Fax: +33 (0) 1 53 83 07 48 
Date/Version 
  February 7th, 2022 / Version 7.0 
 

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CONTACTS 
Sponsor 
ABIVAX 
5 rue de la Baume 
75008 PARIS - France 
Dr Sophie Biguenet 
Chief Medical Officer 
Tel: + 33 (0) 6 3648 7644 
Dr Paul GINESTE 
Senior Director, Clinical Operations 
Tel: + 33 (0) 1 53 83 09 61 
 
Coordinating investigator 
Prof. Severine Vermeire 
University Hospitals Leuven - campus Gasthuisberg 
Gastroenterology 
Herestraat 49 - box 7003 08 
3000 Leuven 
Belgium 
Statistical Analysis 
Dr. Sandor Fritsch 
F. Hochedlinger gasse 23/18 
1020 Vienna 
Austria 
Study Conduct, Data 
management 
Simbec-Orion 
Centre d’Affaires La Boursidière 
Bâtiment le Jura, BP 141 
92357 Le Plessis- Robinson Cedex 
France 
Imaging Central Review 
Bioclinica 
72 Hammersmith Road, 6th Floor  
London, W14 8UD- United Kingdom 
miRNA-124 determination 
Biogazelle 
Technologiepark-Zwijnaarde 82,  
9052 Gent - Belgium 
Pharmacovigilance 
IntuVigilance Limited 
Cardinal Point 
Park Road, 
Rickmansworth WD3 1RE 
Hertfordshire, UK 
Hotline phone: +44 800 689 4129 
Email Address: safety@intuvigilance.com 
Fax number: +44 800 915 6753 
 
 
 

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INVESTIGATOR AGREEMENT PAGE 
 
EudraCT number  
 
2017-003284-35 
Detailed Title:  
A follow-up Phase IIa study to evaluate the long-term safety and efficacy 
profile of ABX464 given at 50 mg once daily in subjects with Moderate to 
Severe Active Ulcerative Colitis. 
 
 
I have carefully read all the pages of this clinical study protocol and I agree to the following:  
• 
To conduct the study as outlined in the protocol, any mutually agreed future protocol amendments and with 
all the terms and conditions set out by ABIVAX. 
• 
Not to implement any changes in the procedures described in the protocol without the prior approval of the 
sponsor and prior to review and written approval by the Ethics Committee and/or Regulatory Authorities, 
unless instructed otherwise by the Regulatory Authorities or the wellbeing of subjects is jeopardized. 
• 
To conduct the study in accordance with the Good Clinical Practice ICH E6 (R2) guidelines, US 21 Code of 
Federal Regulations dealing with clinical studies (including parts 50 and 56 concerning informed consent and 
IRB regulations), the European Union Clinical Trials Directive 2005/28/EC, the provisions of the Helsinki 
Declaration, and relevant legislation in force.  
• 
I am thoroughly aware of the study drug specifications and adverse events as described in the protocol and 
the current Investigator’s Brochure and any other information provided by the Sponsor. 
• 
To ensure that sub-investigator(s) and other relevant members of my staff involved in the study are fully 
aware of their responsibilities regarding this study and will conduct the study according to the protocol.  
 
Investigator’s Name:  
 
 
________________________________________ 
Investigator’s Signature:   
 
________________________________________ 
Date:  
 
 
 
 
________________________________________ 
 
 

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TABLE OF CONTENTS 
CONTACTS 
3 
SYNOPSIS 
9 
1. 
INTRODUCTION AND STUDY RATIONALE 
14 
1.1. 
ULCERATIVE COLITIS (UC) 
14 
1.1.1. 
DISEASE 
14 
1.1.2. 
MANAGEMENT OF SUBJECTS 
14 
1.2. 
ABX464 RATIONALE 
14 
1.2.1. 
INVESTIGATIONAL TREATMENT DESCRIPTION 
14 
1.2.2. 
INVESTIGATIONAL PRODUCT DESCRIPTION 
15 
1.2.3. 
INVESTIGATIONAL PRODUCT MODE OF ACTION 
15 
1.2.4. 
PRECLINICAL DATA OF ABX464 
17 
1.2.4.1. 
NON-CLINICAL BACKGROUND INFORMATION 
17 
1.2.5. 
PREVIOUS CLINICAL EXPERIENCE WITH ABX464 
18 
1.3. 
RATIONALE FOR THE CLINICAL STUDY AND STUDY DESIGN 
20 
2. 
STUDY OBJECTIVES AND ENDPOINTS 
22 
2.1. 
PRIMARY OBJECTIVE 
22 
2.2. 
SECONDARY OBJECTIVES 
22 
2.3. 
PRIMARY ENDPOINT 
22 
2.4. 
SECONDARY ENDPOINTS 
22 
3. 
INVESTIGATIONAL PLAN 
24 
3.1. 
STUDY DESIGN 
24 
3.1.1. 
DESIGN AND METHODOLOGY 
24 
3.1.2. 
DATA SAFETY MONITORING BOARD – INDEPENDENT CARDIOVASCULAR SAFETY COMMITTEE (ICVSC) 
24 
3.2. 
DURATION OF STUDY PARTICIPATION 
24 
4. 
STUDY POPULATION 
25 
4.1. 
NUMBER OF SUBJECTS/CENTERS 
25 
4.2. 
ELIGIBILITY CRITERIA 
25 
4.2.1. 
INCLUSION CRITERIA 
25 
4.2.2. 
EXCLUSION CRITERIA 
25 
5. 
STUDY ASSESSMENTS AND PROCEDURES 
26 
5.1. 
STUDY FLOW CHART 
26 
5.2. 
STUDY CONDUCT 
26 
5.2.1. 
DAY 0 (D56 VISIT OF THE ABX464-101 STUDY) 
26 
5.2.2. 
DAY 7, 14, 21, 42 VISITS (± 2 DAYS) 
27 
5.2.3. 
DAY 28, DAY 56/M2, MX+1 VISITS (28 ± 4 DAYS) UNTIL M24 
27 
5.2.4. 
M27 UNTIL M45 (CALENDAR MONTH ± 14 DAYS) 
27 
5.2.5. 
M48 (CALENDAR MONTH ± 14 DAYS) 
28 
5.2.6. 
END OF STUDY VISITS 
28 
5.3. 
DETAIL OF THE STUDY ASSESSMENTS 
29 
5.3.1. 
ECHOCARDIOGRAPHY 
29 
5.3.3. 
PHYSICAL EXAMINATION AND VITAL SIGNS 
29 
5.3.4. 
PREGNANCY 
30 
5.3.5. 
ECG 
30 
5.3.6. 
MIR-124 EXPRESSION LEVEL DETERMINATION 
30 
5.3.7. 
SF-36 QUESTIONNAIRE (SF-36) 
30 
5.3.8. 
PARTIAL/TOTAL MAYO SCORE 
30 
5.3.9. 
SIGMOIDOSCOPY 
31 
5.3.10. 
CLINICAL REMISSION, CLINICAL RESPONSE, AND CORTICOSTEROID-FREE CLINICAL REMISSION 
31 
5.3.11. 
ENDOSCOPIC IMPROVEMENT AND ENDOSCOPIC REMISSION 
31 
5.3.12. 
HEMATOLOGY AND BIOCHEMISTRY 
31 
6. 
INVESTIGATIONAL PRODUCT(S) 
33 
6.1. 
DESCRIPTION OF INVESTIGATIONAL TREATMENT 
33 
6.2. 
DESCRIPTION OF INVESTIGATIONAL PRODUCT 
33 
6.2.1. 
ACTIVE INVESTIGATIONAL PRODUCT (ABX464) 
33 
6.3. 
ADMINISTRATION AND DOSING 
33 
6.3.1. 
ADMINISTRATION OF THE INVESTIGATIONAL PRODUCT 
33 
6.3.2. 
GUIDELINES FOR TREATMENT POSTPONEMENT AND DOSE MODIFICATIONS 
33 
6.4. 
METHOD OF ASSIGNING SUBJECTS TO TREATMENT ARMS 
33 
6.5. 
PACKAGING 
34 
6.6. 
STORAGE 
34 
6.7. 
PRODUCT ACCOUNTABILITY 
34 

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6.8. 
PRIOR AND CONCOMITANT MEDICATION 
34 
6.8.1. 
ALLOWED CONCOMITANT TREATMENT 
34 
6.8.2. 
PROHIBITED CONCURRENT MEDICATIONS 
34 
7. 
SUBJECT COMPLETION AND WITHDRAWAL 
36 
7.1. 
SUBJECT COMPLETION 
36 
7.2. 
STUDY DISCONTINUATION CRITERIA 
36 
7.3. 
STUDY DISCONTINUATION 
37 
8. 
ADVERSE EVENTS (AE), ADVERSE EVENT OF SPECIAL INTEREST (AESI) AND SERIOUS ADVERSE EVENTS (SAE) 
38 
8.1. 
DEFINITION OF AN AE 
38 
8.2. 
DEFINITION OF AN AESI 
38 
8.3. 
DEFINITION OF A SAE 
40 
8.3.1. 
EVENTS AND/OR OUTCOMES NOT QUALIFYING AS SAES 
41 
8.4. 
EVENTS OR OUTCOMES QUALIFYING AS AES OR SAES 
41 
8.4.1. 
CLINICAL LABORATORY PARAMETERS 
41 
8.4.2. 
PREGNANCY REPORT 
41 
8.5. 
TIME PERIOD, AND FREQUENCY OF DETECTING AES, AESIS AND SAES 
41 
8.6. 
RECORDING AES AND SAES 
42 
8.7. 
REPORTING OF AESIS AND SAES TO ABIVAX OR ITS DESIGNEE 
42 
8.8. 
REPORTING OF SAES/ TO REGULATORY AUTHORITIES 
44 
9. 
DATA ANALYSIS AND STATISTICAL CONSIDERATIONS 
45 
9.1. 
STATISTICAL AND ANALYTICAL PLANS 
45 
9.1.1. 
PROTOCOL DEVIATIONS 
45 
9.1.2. 
DEFINITION OF STUDY ANALYSIS SETS 
45 
9.1.3. 
SUBJECTS/SUBJECTS DISPOSITION 
45 
9.1.4. 
DEMOGRAPHIC AND OTHER BASELINE CHARACTERISTICS 
45 
9.1.5. 
TREATMENT COMPLIANCE 
45 
9.2. 
EFFICACY ANALYSIS 
46 
9.3. 
SAFETY ANALYSES 
46 
9.3.1. 
CLINICAL LABORATORY EVALUATION 
46 
9.4. 
DETERMINATION OF SAMPLE SIZE 
47 
10. STUDY CONDUCT CONSIDERATION 
48 
10.1. 
REGULATORY AND ETHICAL CONSIDERATIONS 
48 
10.1.1. 
GENERAL REQUIREMENTS 
48 
10.1.2. 
INDEPENDENT ETHICS COMMITTEE/INSTITUTIONAL REVIEW BOARD 
48 
10.1.3. 
SUBJECT INFORMED CONSENT 
49 
10.1.4. 
COMPENSATION TO SUBJECTS 
49 
11. STUDY MANAGEMENT 
50 
11.1. 
REMOTE DATA ENTRY 
50 
11.2. 
DATA MANAGEMENT 
50 
11.3. 
DATA CODING 
50 
11.4. 
STUDY MONITORING 
50 
11.5. 
RECORDS RETENTION 
51 
11.6. 
QUALITY ASSURANCE AND INSPECTION BY AUTHORITIES 
51 
11.7. 
STUDY AND SITE CLOSURE 
52 
11.8. 
STUDY REPORT AND PUBLICATION 
52 
11.9. 
OWNERSHIP AND CONFIDENTIALITY 
52 
12. REFERENCES 
53 
13. APPENDICES 
54 
 
 

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ABBREVIATIONS 
Abbreviation or Term 
Definition 
AE 
adverse event 
AESI 
Adverse event of special interest  
ALT/SGPT 
alanine aminotransferase/serum glutamic pyruvate transaminase 
AST/SGOT 
aspartate aminotransferase/serum glutamic oxaloacetic transaminase 
AUC 
area under the plasma concentration 
BMDM 
Bone Marrow Derived Macrophages 
CBC 
Cap Binding Complex 
Cmax 
peak plasma concentration 
CPK 
Creatine PhosphoKinase 
CRF 
case report form 
CRP 
C-Reactive Protein 
CTC-AE 
Common Terminology Criteria for Adverse Events 
DSMB 
Data and Safety Monitoring Board 
DSS 
Dextran Sodium Sulfate 
ECG 
electrocardiogram 
EDTA 
ethylenediaminetetraacetic acid 
ESR 
Erythrocyte Sedimentation Rate 
Frel 
relative bioavailability 
GCP 
good clinical practice 
GGT 
gamma-glutamyl transferase 
GLS 
Global Longitudinal Strain 
GM 
geometric mean 
H 
hours 
HIV 
Human Immunodeficiency Virus 
HR 
heart rate 
hs 
Hyper sensitivity 
IB 
Investigator’s Brochure 
IBD 
Inflammatory Bowel Disease 
ICF 
informed consent form  
ICH 
International Conference on Harmonization 
ICVSC 
Independent Cardiovascular Safety Committee 
IEC 
Independent Ethics Committee 
Il-6 
Interleukin 6 
IL-22 
Interleukin 22 
IMP 
Investigational Medicinal Product 
IRB 
Institutional Review Board 
IUD 
Intra-Uterine Device 
LFTs 
Liver Function Tests 
LPS 
Lipopolysaccharide 
LVEF 
Left Ventricle Ejection Fraction 
Max 
maximum 
MCS 
Mayo Score 
MCP-1 
Monocyte Chemoattractant Protein-1 
MedDRA 
Medical Dictionary for Regulatory Activities 
mg 
milligram 
Min 
minimum 
miR 
micro-RNA 
mL 
milliliter 
NOAEL 
No Observed Adverse Effect Level 
NT-ProBNP 
N-terminal pro-brain natriuretic peptide 
o.d. 
Once Daily 
PBMC 
Peripheral Blood Mononuclear Cells 
PCSA 
potentially clinically significant abnormalities 
PD 
pharmacodynamics 
PK 
pharmacokinetics 
PP 
Per Protocol 
qPCR 
Quantitative Polymerase Chain Reaction 
QTc 
heart-rate–corrected QT interval (time between the start of the Q wave and the end of the T wave in the 
heart's electrical cycle) using Bazett’s formula 
R 
Accumulation ratio 
RV 
Right Ventricle 
RNA 
Ribonucleic Acid 
SAE 
serious adverse event 
SD 
standard deviation 
SEM 
standard error of the mean 
SF-36 
Quality of Life Questionnaire 
STAT-3 
signal transducer and activator of transcription 3 

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t1/2 
terminal half-life 
TEAE 
treatment emergent adverse event 
tlag 
interval between administration time and the sampling time preceding the first concentration above the limit 
of quantification 
TMS 
Total Mayo Score 
TNF 
Tumor Necrosis Factor 
UC 
Ulcerative Colitis 
ULN 
Upper Limit of Normal range 
WOCBP 
Women of Child Bearing Potential 
 
 

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SYNOPSIS 
Study n° 
ABX464-102 
Clinical Phase 
IIa 
 
 
Type of Study 
Follow-up Study  
Study title 
A follow-up Phase IIa study to evaluate the long-term safety and efficacy profile of ABX464 
given at 50 mg once daily in subjects with Moderate to Severe Active Ulcerative Colitis. 
Short title 
Follow-up study in Moderate to Severe Active Ulcerative Colitis subjects. 
Investigators and study 
centers 
Active sites from previous study (ABX464-101) located in Belgium, Hungary and Poland. 
Study period 
Q4 2017 – Q3 2022 
Investigational product 
ABX464 is a small molecule that binds the cap binding complex (CBC), comprised of two proteins 
CBP20 and CBP80, within the cell nucleus. This binding leads to an increased expression of a 
single micro-RNA (miR-124) by impacting the splicing of a single long non-coding RNA. Because 
of its action on this single splicing event, leading to an increase in miR-124, a microRNA with 
potent anti-inflammatory properties, ABX464 potentially has broad applicability across a 
variety of inflammatory diseases. ABX464 is currently under investigation as a potential 
treatment for Rheumatoid Arthritis (RA) and inflammatory bowel diseases (IBD). As of 30 
November 2021, 1023 subjects have received ABX464, according to various administration schedules, 
in all completed, and ongoing open-label clinical studies across all indications. Out of these 1023 
subjects, 830 subjects have been dosed with ABX464 50mg once daily (od) including 240 
subjects for longer than 6 months with 197 for more than a year. In addition, 36 subjects have 
received ABX464 or placebo in ongoing blinded clinical study (ABX464-921). All doses tested were well 
tolerated. 
Study Design and 
Methodology 
This study is an open-label study aiming at evaluating the long-term safety and the efficacy 
profile of ABX464 given once a day (o.d) at 50 mg in subjects who have been previously enrolled 
in the ABX464-101 clinical study (induction study) and who are willing to continue their 
treatment. 
All subjects will receive ABX464 given at 50 mg o.d irrespective of their previous treatment 
received in the ABX464-101 study (i.e. ABX464 or Placebo). 
The actual treatment received by a subject throughout the previous study (ABX464-101) will 
not be known at the time the subjects enter this follow-up study.  
The enrolment in this follow-up study will be based on the willingness of the subject to carry 
on his/her participation and also based on investigator’s judgement. 
Subjects will be treated with ABX464 for an overall period of 48 months. Subjects will be 
followed up weekly during the first month, every two weeks during the second month and then 
on a monthly basis until M24, then quarterly from M24 to M48. 
At M48, depending on their clinical response, eligible patients willing to continue study 
treatment will be offered to take part into a long term follow up safety study (ABX464-108 
study). ABX464-108 study is a separate study requiring health authorities and ethics 
committees’ approval. If patients are not eligible to pursue treatment in this long-term follow-
up study, they will be followed for 4 additional weeks for safety purposes before End of study 
Visit. 
Study Objectives 
Primary Objective 
The primary objective of the study is to evaluate the long-term safety of ABX464 given at 50 
mg once daily in subjects with Moderate to Severe Active Ulcerative Colitis. 
Secondary Objectives 
The secondary objectives are: 
▪ 
To evaluate the long-term effect of ABX464 on clinical and endoscopic remission in 
subjects with Moderate to Severe Active Ulcerative Colitis assessed by the Mayo Score 
(MCS). 
▪ 
To evaluate the long-term effect of ABX464 on inflammatory markers (C-Reactive Protein 
(CRP), Calprotectin and Erythrocyte Sedimentation Rate (ESR) 
▪ 
To evaluate the long-term of ABX464 on Quality of Life (QoL) measured by the SF-36 
questionnaire in subjects with Moderate to Severe Active Ulcerative Colitis until M24. 

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Study n° 
ABX464-102 
Clinical Phase 
IIa 
 
 
Type of Study 
Follow-up Study  
The echocardiography objective is: 
To evaluate the effect of ABX464 on cardiac function as assessed through echocardiograms. 
 
Study Endpoints 
 
Primary Endpoint: 
▪ 
Number of incidences of treatment-emergent adverse events in ABX464 treated 
subjects. 
Secondary Endpoints: 
▪ 
The change from Day 0 in Total Mayo Score. 
▪ 
The change from Day 0 in Partial Mayo Score. 
▪ 
The time to UC worsening. 
▪ 
The change from Day 0 in fecal calprotectin, CRP levels and ESR. 
▪ 
The scores and changes from Day 0 in SF-36 Questionnaire scores. 
▪ 
The miR-124 expression at month 12, month 36 and month 48. 
▪ 
The number of incidences of treatment-emergent serious adverse events. 
▪ 
The number of incidences of treatment-emergent adverse events of special interest. 
▪ 
The number of incidences of adverse events leading to investigational product 
discontinuation. 
▪ 
The number of incidences of specific laboratory abnormalities. 
▪ 
Percentage of subjects reaching clinical remission at M12, M36, and M48. 
▪ 
Percentage of subjects reaching clinical response at M12, M36, and M48. 
▪ 
Percentage of subjects reaching endoscopic improvement at M12, M36, and M48. 
▪ 
Percentage of subjects reaching endoscopic remission at M12, M36, and M48. 
▪ 
Percentage of subjects reaching corticosteroid-free clinical remission at M12, M36, 
and M48. 
The echocardiography secondary endpoints are: 
▪ 
Absolute (%) change-from-previous echocardiogram of Left ventricle Ejection Fraction 
(LVEF) as measured by 2-dimensional echocardiography 
▪ 
Number of subjects with a clinically relevant reduction (change-from-previous 
echocardiogram) of LVEF, defined as by > 10% reduction (absolute percentage points) to a 
value < 50% 
▪ 
Absolute (%) change in Global Longitudinal Strain (GLS) from-previous echocardiogram 
▪ 
Number of subjects with a relative percentage reduction in GLS by > 15% from the previous 
value 
▪ 
Number of subjects with a reduction of LVEF > 10% (absolute percentage points) to a value 
≥ 50% with an accompanying fall in GLS > 15%  
▪ 
Number of subjects with a reduction in LVEF by > 10% (absolute percentage points) to a 
value ≥ 50% 
▪ 
Changes from previous echocardiography of other echocardiographic parameters as 
described in a standard protocol, including 2-dimensional volumes, RV size and systolic 
function and valve function. 
Main Selection Criteria 
 
Inclusion criteria: 
A subject will be eligible for inclusion in this study only if ALL of the following criteria apply: 
▪ 
Subjects previously enrolled in the ABX464-101 clinical study who have completed the 
initial 2-month treatment phase; 
▪ 
Subjects able and willing to comply with study visits and procedures; 
▪ 
Subjects with hematological and biochemical laboratory parameters as follows at the 
D56 visit of the ABX464-101 study: 
o 
Hemoglobin > 9.0 g dL-1; 
o 
Absolute neutrophil count ≥ 750 mm-3; 
o 
Platelets ≥ 100,000 mm-3; 

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Study n° 
ABX464-102 
Clinical Phase 
IIa 
 
 
Type of Study 
Follow-up Study  
o 
Total serum creatinine ≤ 1.3 x upper limit of normal (ULN); 
o 
Creatinine clearance > 50 mL min-1 by the Cockcroft-Gault equation; 
o 
Total serum bilirubin < 1.5 x ULN; 
o 
Alkaline phosphatase, AST (SGOT) and ALT (SGPT) < 1.5 x ULN; 
▪ 
Subjects should understand, sign and date the written voluntary informed consent form 
at the enrolment visit prior to any protocol-specific procedures being performed; 
▪ 
Females and males receiving the study treatment and their partners must agree to use 
a highly effective contraceptive method during the study and for 6 months after end of 
study or early termination. Contraception should be in place at least 3 months prior to 
study participation. Women must be surgically sterile or if of childbearing potential must 
use a highly effective contraceptive method. Women of childbearing potential (WOCBP) 
will enter the study after confirmed menstrual period and a negative pregnancy test. 
Highly effective methods of contraception include true abstinence, intrauterine device 
(IUD) or hormonal contraception aiming at inhibition of ovulation, intrauterine hormone 
releasing system, bilateral tubal ligation, vasectomized partner. True abstinence is 
defined when this is in line with the preferred and usual lifestyle of the patient. In each 
case of delayed menstrual period (over one month between menstruations) 
confirmation of absence of pregnancy is required. This recommendation also applies to 
WOCBP with an infrequent or irregular menstrual cycle. Female and male patients must 
not be planning pregnancy during the trial and for 6 months post completion of their 
participation in the trial. In addition, male participants should use condoms and should 
not donate sperm as long as contraception is required. 
▪ 
Exclusion Criteria: 
The following criterion should be checked at the time of screening. If this exclusion criterion 
applies, the subject will not be included in the study: 
▪ 
Any condition, which in the opinion of the investigator, could compromise the subject's 
safety or the adherence to the study protocol. 
Medications 
Mandatory and/or allowed Concomitant Medications: 
▪ 
ABX464 administered once daily at 50 mg 
▪ 
Oral 5-aminosalicylic acid at stable dose. 
▪ 
Immunosuppressants in the form of azathioprine, 6-mercaptopurine, or methotrexate 
at stable dose. 
▪ 
Antidiarrheals (e.g., loperamide, diphenoxylate with atropine) at stable dose. 
▪ 
COVID-19 vaccines are allowed. 
Prohibited Concomitant Medications: 
▪ 
Anti-tumor necrosis factor (TNF) therapies. 
▪ 
Vedolizumab. 
▪ 
JAK inhibitors. 
▪ 
Topical corticosteroids and topical 5-aminosalicylic acid preparations. 
▪ 
Cyclosporine and tacrolimus. 
▪ 
Drugs that could interact with ABX464 should be avoided especially the CYP1A2 
inducers/inhibitors. The following CYP1A2 inducers/inhibitors are prohibited during the 
whole course of the study (ciprofloxacin, enoxacin, fluvoxamine, montelukast, 
phenytoin, rifampicin, ritonavir, teriflunomide). The UGT1A9 inhibitors and OAT 
P1B1/P1B3 inhibitors/substrates that could interact with ABX464 and its metabolite 
ABX464-N-Glu should also be avoided. 
▪ 
Use of any investigational or non-registered product within 3 months preceding Day 0 
except ABX464. 
Study discontinuation 
Subjects who are not found eligible or not willing to enter the ABX464-108 study are not considered as 
prematurely discontinued as they have completed the scheduled treatment of ABX464-102 study. 
Subject’s study discontinuation could occur for the following reasons: 
▪ 
Investigator’s decision; 

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Study n° 
ABX464-102 
Clinical Phase 
IIa 
 
 
Type of Study 
Follow-up Study  
▪ 
An Adverse Event or an intercurrent condition that preclude continuation of treatment;  
▪ 
Specifically, an increase ≥ 3.0 x ULN in liver transaminases (AST/SGOT and/or 
ALT/SGPT) or an increase ≥ 2.0 x ULN in Alkaline phosphatase or in total bilirubin 
requires close observation with repeating liver enzymes and serum bilirubin tests two 
times weekly and clinical investigation to understand the etiology of this elevation. 
Frequency of retesting can decrease to once a month if abnormality stabilizes after the 
initial two weeks of follow-up and if the patient is asymptomatic.  
Discontinuation of the study treatment should occur if: 
• 
ALT or AST > 8xULN 
• 
ALT or AST > 5xULN for more than 2 weeks 
• 
ALT or AST > 3xULN and total bilirubin > 2xULN or INR>1.5 
• 
ALT or AST > 3xULN with appearance of fatigue, nausea, vomiting, right upper 
quadrant pain or tenderness, fever, rash, and/or eosinophilia (>5%); 
▪ 
Severe (grade 3 or higher) infection, a severe (grade 3 or higher) opportunistic 
infection, or sepsis; 
o 
Any cardiac AESI or condition diagnosed during the course of the study and assessed 
by the clinical adjudication committee as changing the risk/benefit balance for the 
subject; 
o 
New onset of acute pancreatitis; 
o 
Malignancies (including non-melanoma skin cancers); 
o 
Any relevant toxicity or negative change in the risk/benefit assessment leading to an 
unacceptable risk for the subject or any data deriving from other clinical trials or 
toxicological studies which negatively influence the risk/benefit assessment. This may 
be applicable but is not limited to the following cases: occurrence of AEs which 
character, severity or frequency is new in comparison to the existing risk profile, or 
clinically significant abnormal laboratory results, including new onset anemia 
(defined as a hemoglobin decrease >2 g/dL from baseline or hemoglobin <8 g/dL 
▪ 
Worsening of the UC defined as a 2-point increase in the pMMS, with pMMS ≥ 4 on 2 
separate occasions 7 day-apart and confirmed by an endoscopy sub score of 2 points or 
higher; subject who would experience a treatment failure during the study may be withdrawn at 
any time. S/he will have to be treated according to standard of care as soon as s/he is discontinued 
from study treatment because of study withdrawal; 
▪ 
Withdrawal of consent; 
▪ 
Pregnancy; 
▪ 
Patients included with a history of cardiac ischemic disease and/or congestive heart failure will be 
discontinued from the study, will perform the End of Study Visit 4 weeks after last study drug 
administration and will then be treated according to the standard of care upon study 
treatment interruption.  
▪ 
Administrative reasons from Sponsor. 
Data Safety Monitoring 
Board (DSMB) - 
Independent 
Cardiovascular Safety 
Committee (ICVSC) 
A Data Safety Monitoring Board with expertise and experience in the management in UC will 
review the safety of the trial on a monthly basis until December 2019 and then quarterly from 
January 2020 onwards. 
An Independent Cardiovascular Safety Committee (ICVSC), comprised of 3 cardiologists with 
experience from drug development, will be formed as detailed in the Charter. The ICVSC will be 
responsible for an on-going evaluation of cardiac adverse events of special interest (Cardiac AESIs), for 
treatment emergent echocardiographic findings, and for treatment emergent changes of cardiac safety 
biomarkers (as detailed above). The ICVSC will review cardiac adverse events on an on-going basis, 
meet regularly and provide recommendations to Sponsor and DSMB regarding study procedures and 
conduct. 
Sample Size calculation 
Not applicable / Maximum 30 subjects (i.e. ABX464-101’s sample size) 
Statistical Methods 
 
Safety: 

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Study n° 
ABX464-102 
Clinical Phase 
IIa 
 
 
Type of Study 
Follow-up Study  
Analysis of safety will be performed on the safety data set consisting in all subjects who 
received at least one dose of ABX464 in the study. The assessment of safety will be based on 
the frequency of adverse events (with and without regard to causality) graded according to the 
Common Terminology Criteria for Adverse Events “CTC-AE” (Version 5.0) and also, the review 
of individual values for clinical laboratory data, vital signs and ECG focusing on the detection of 
abnormal values and potentially clinically significant abnormalities (PCSAs) determined upon 
investigator considerations. 
All adverse events will be listed and the data will be tabulated by body system/organ class. 
Adverse event tabulations will include all treatment emergent adverse events, which will be 
further classified by severity, and relationship to treatment. 
Clinical laboratory parameters, echocardiography parameters, vital signs, and ECG will be 
summarized by using descriptive statistics (n, mean, SD, SEM, median, minimum and 
maximum). Number of subjects with at least one abnormal value will be tabulated (counts and 
percentages) for each parameter in summary shift tables. 
Efficacy:  
Efficacy results will be presented descriptively; proper tests will be performed if appropriate. 
 
 
 

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1. INTRODUCTION AND STUDY RATIONALE 
1.1. 
Ulcerative Colitis (UC)  
1.1.1. Disease 
Ulcerative colitis (UC) is a chronic inflammatory condition causing continuous mucosal inflammation of the colon 
without granulomas on biopsy, affecting the rectum and a variable extent of the colon in continuity, which is 
characterized by a relapsing and remitting course. 
UC is a lifelong disease arising from an interaction between genetic and environmental factors, observed 
predominantly in the developed countries of the world. 
The precise etiology is unknown and therefore medical therapy to cure the disease is not yet available. 
1.1.2. Management of subjects 
Subjects may live with a considerable symptom burden despite medical treatment (66% describe interference 
with work and 73% with leisure activities[1] in the hope that the etiology of ulcerative colitis will shortly be 
revealed, and a cure emerge. 
Although most subjects present with mild-to-moderate UC, 10% of subjects initially present with severe disease. 
Additionally, approximately 15% of subjects will develop a severe flare during the course of their lifetime. Both 
the American College of Gastroenterology practice guidelines and the European Crohn's and Colitis Organization 
position statements define severe colitis similarly as the passage of six or more stools per day with evidence of 
systemic toxicity (e.g., fever, tachycardia, anemia or elevated ESR) [2,3]. 
Subjects with acute severe UC require hospitalization for optimal management owing to the seriousness of their 
illness. Although rates of death in severe UC have dropped by up to 25% with the adoption of more aggressive 
monitoring and treatment [4] acute severe colitis is still associated with a measurable mortality [5]. 
The use of intravenous steroids and improved surgical techniques probably explain much of the reduction in 
mortality associated with acute severe UC observed in the decades since their introduction [6]. 
Severe UC should be considered a medical emergency, and subjects require close monitoring of stool frequency 
and vitals symptoms. Serial abdominal examinations and plain radiographs should be performed. 
The cornerstone of management of severe UC remains the use of intravenous corticosteroids, which are effective 
in the induction of remission in the majority of cases. While many subjects with acute severe ulcerative colitis 
will respond to a short course of intravenous corticosteroids, up to a third will fail to improve. In these subjects 
with steroid-refractory colitis, the choice is between rescue medical therapy with ciclosporin, anti-TNF Alpha, 
vedolizumab or surgery. Anti-tumor necrosis factor (TNF) therapy is effective for the treatment of UC.  
Nevertheless, up to 30% of subjects show no clinical benefit, while another 40% lose response over time and 
need to escalate or discontinue anti-TNF therapy within one year of treatment. 
Thus, there is an unmet medical need for novel treatment options for patients with moderate to severe UC. 
1.2. 
ABX464 rationale 
1.2.1. Investigational treatment description 
ABX464 is a first-in-class, orally available, small molecule with anti-inflammatory activity which is under 
investigation as a potential treatment for moderate to severe ulcerative colitis and rheumatoid arthritis. 
ABX464 binds the Cap Binding Complex (CBC) comprised of two proteins CBP20 and CBP80, within the cell 
nucleus. This binding leads to an increased expression of a single micro-RNA (miR-124) by impacting the splicing 
of a single long non-coding RNA. Because of its action on this single splicing event, leading to an increase in miR-
124, a microRNA with potent anti-inflammatory properties, ABX464 potentially has broad applicability across a 
variety of inflammatory diseases. ABX464 is currently under investigation as a potential treatment for 
Rheumatoid Arthritis (RA) and inflammatory bowel diseases (IBD).   

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In humans, ABX464 is conjugated via glucuronidation to ABX464-N-Glu, which contributes the majority of ABX464 
plasma exposure. ABX464-N-Glu is pharmacologically active and also binds to the CBC leading to an increase in 
miR124 expression.  
1.2.2. Investigational product description  
ABX464 has the following chemical structure: 
 
 
The chemical name of the molecule is 8-chloro-N-[4-(trifluoromethoxy) phenyl]quinolin-2-amine, or (8-chloro-
quinolin-2-yl)-(4-trifluoromethoxy-phenyl)-amine. Its molecular weight is 338.7 g/mol. 
The study drug is formulated as hard gelatin, powder-filled capsules (size 01). 
1.2.3. Investigational product Mode of Action 
ABX464 upregulates MiR-124 in vitro in several cell types 
MiR-124 induction by ABX464 in Human Peripheral blood mononucleated cells (PBMCs) has been demonstrated 
as follows: 
• 
Affymetrix genechip miRNA array 2.0 which contains 15644 miRNA probes representing 1105 miRNA 
across 131 organisms. The chip also contains 2202 pre-miR probes and 2334 probes for snoRNA and 
scaRNA. 
• 
TaqMan® Array Human MicroRNA which contains 196 miRNAs. 
 
Both approaches demonstrated that only miR-124 was upregulated by ABX464 treatment across species and that 
no miRNAs were downregulated. The expression of miR-124 was significantly increased (about 13-fold) by 
ABX464. MiR-124 was upregulated after ABX464 treatment in both CD4+ and CD8+ T cells. 
The effects of ABX464 on miR-124 expression was tested in Human Monocyte-Derived Macrophages (HuMDM). 
The results demonstrated that using Real Time Taqman quantitative polymerase chain reaction (qPCR), ABX464 
is able to up-regulate the expression of miR-124 in HuMDM. 
MiR-124 is encoded from three independent genes, miR-124-1, miR-124-2, and miR-124-3, located on human 
chromosomes 8 and 20. The specific upregulation of miR-124 in CD4+ cells was demonstrated to be the result of 
the action of ABX464 on the splicing of long non-coding RNA 0599-205 located in miR-124-1, one of the three 
loci expressing miR-124.  
ABX464 upregulates miR-124 in treated patients with moderate to severe ulcerative colitis  
After 8 weeks of treatment (57 days) with ABX464 at doses of 25, 50 or 100 mg, the number of miR-124 copies 
in rectal biopsies and in blood were significantly higher in all ABX464 groups compared to placebo (Figure 1 and 
Figure 2). 
 
 
 
 

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Figure 1: MiR 124 induction in rectal biopsies of patients treated with ABX464 in the phase 2b trial (UC) 
 
Figure 2 : MiR 124 induction in blood of patients treated with ABX464 in the phase 2b trial (UC) 
 
ABX464 reduces pro-inflammatory cytokines/chemokines 
ABX464 reduced the expression of pro-inflammatory chemokines/cytokines MCP1 (-50%), CXCL1 (-20%), IL-10 (-
30%), IL-1β (-25%), TNFα (-25%) and IL-6 (-20%) within 4 days of treatment of HuMDM polarized to M1 
phenotype. 
In vivo evidence for the role of ABX464 in inflammation 
ABX464 decreases pro-inflammatory cytokines  
The results observed in HuMDM were confirmed in vivo in the mouse model of Dextran Sulfate Sodium (DSS) 
induced colonic inflammation. Following concomitant 10 days of DSS exposure and ABX464 treatment, ABX464 
induced a significant marked reduction of pro-inflammatory cytokines: TNFα (7.5-fold reduction), IL-6 (2-fold 
reduction), and MCP1 (6-fold reduction in the distal and middle regions) in the supernatant of mouse colons that 
were incubated for 24 hours in culture medium. 
ABX464 decreases the pro-inflammatory Th17 CD4+ cell subset  
Th17 cytokines, that include IL-17, IL-23, and IL-22, are often increased in the inflamed intestinal mucosa of active 
UC and Crohn’s disease (CD) patients relative to unaffected regions and healthy controls [7]. In PBMCs, ABX464 
treatment did not affect the Treg populations but significantly reduced the number of Th17 and Th1 population 
and increased Th 2 cells population. Th17 cells are known to differentiate in response to IL-1β, IL6 and IL23 
through STAT3 pathway, one of the targets of miR-124 [8]. Proinflammatory Th17 cells are increased in the 
mesenteric lymph nodes of DSS-exposed mice, ABX464 prevented this increase of Th17 in mesenteric lymph 
nodes of DSS mice. 

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IL-17 secretion was also tested during the course of the phase 2b clinical trial in ulcerative colitis (ABX464-103). 
A statistically significant decrease in IL-17 in the sera of the patients has been shown for patients dosed with 
ABX464 compared to placebo. 
ABX464 reduces disease severity in an acute DSS-induced colitis model 
Compared with mice untreated with ABX464, a reduced DSS-induced weight loss was observed in mice receiving 
ABX464. The weight of ABX464-treated mice returned to pre-treatment levels and the mice displayed decreased 
disease parameters including smaller and fewer colonic lesions as well as smaller reductions of colon length. 
ABX464 decreased macrophages recruitment during acute colitis.  
1.2.4. Preclinical data of ABX464 
 
1.2.4.1. 
Non-clinical background information 
The toxicity of ABX464 and ABX464-N-Glu was studied in a range of rodent and nonrodent species (rats, rabbits, 
dogs, cynomolgus and marmoset monkeys, and mini-pigs) with treatment durations ranging from 2-weeks to 6/9 
months. These studies have demonstrated that ABX464 and ABX464-N-Glu are overall well tolerated. Vomiting 
and ptyalism were the major clinical sign, and the main target organs of ABX464 toxicity were the gastro-
intestinal tract and the liver. The adverse effects noted on these organs were essentially mild/moderate but 
showed reversibility during the recovery phases. 
Plasma exposure to ABX464 and ABX464-N-Glu in humans (based on predicted steady-state exposure in 
ulcerative colitis patients at the highest proposed dose of 100mg) are calculated as being approximately parity 
(Cmax) to 4-fold (AUC) for ABX464 and 9-fold (Cmax) to 2-fold (AUC) for ABX464-N-Glu exposure as seen in pivotal 
chronic toxicology studies. 
ABX464 had no significant adverse effects on the nervous and respiratory systems, or on cardiovascular function. 
ABX464 was shown to be non-genotoxic and ABX464-N-Glu was shown to be non-mutagenic. 
Genotoxicity:  
ABX464 was found to be non-genotoxic. Its main metabolite, the ABX464-N-Glu was not mutagenic as assessed 
by an Ames test, an in vitro and an in vivo micronucleus assay. 
Reprotoxicity: 
Reproductive toxicity was assessed from fertility to postnatal development, in five studies. In rabbits, the 
maternal NOAEL was considered to be 9mg/kg od and the NOAEL for the embryo-fetal development less than 
1mg/kg od. In rats, the maternal NOAEL and the NOAEL for pup development and survival is considered to be 
lower than 15 mg/kg od. The F1 generation NOAEL is considered to be 40mg/kg od in absence of adverse effect 
at this dose-level. 
Teratogenicity: 
ABX464 appears to have teratogenic activity.  
Hepatocellular toxicity:  
In minipigs the main adverse finding was centrilobular hepatocellular degeneration/necrosis associated with 
hemorrhage, fibrosis and /or extramedullary hematopoiesis observed at dose levels of 10mg/kg and above. The 
liver lesions observed in one of the animals administered 5mg/kg od, were not considered adverse. Based on this 
observation, the NOAEL is 5mg/kg od. 
No signs of hepatotoxicity related to ABX464 have been observed in any of the patients treated with ABX464 in 
clinical trials and DILISym evaluation did not predict any risk of liver toxicity for ABX464 and ABX464-N-Glu. 
Regarding the other observations made from the pre-clinical toxicology program, please refer to the current 
version of the Investigator Brochure. 

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1.2.5. Previous clinical experience with ABX464 
The effect of ABX464 in humans has been assessed in eighteen clinical trials: 
• 
Completed clinical studies in healthy volunteers (ABX464-001, ABX464-002, ABX464-901, ABX464-902, 
and ABX464-903) and controlled studies in patients with ulcerative colitis (ABX464-101 and ABX464-
103), in patients with rheumatoid arthritis (ABX464-301), in HIV infected subjects (ABX464-003, ABX464-
004, and ABX464-005), and in COVID-19 infected patients (ABX464-401). 
• 
Open label studies in ulcerative colitis (ABX464-102, ABX464-104, and ABX464-108) and rheumatoid 
arthritis (ABX464-302).  
• 
A drug product formulation study (ABX464-905) is ongoing in Healthy Volunteers 
• 
A bioequivalence study (ABX464-921) is ongoing in Japanese Healthy Volunteers. 
As of 30 November 2021, 1023 subjects have received ABX464, according to various administration schedules, 
in all completed, and ongoing open-label clinical studies across all indications. Out of these 1023 subjects, 830 
subjects have been dosed with ABX464 50mg once daily (od) including 240 subjects for longer than 6 months 
with 197 for more than a year. In addition, 36 subjects have received ABX464 or placebo in ongoing blinded 
clinical study (ABX464-921). Fourteen patients have received ABX464 50mg od for more than 3 years in the UC 
open label maintenance study (ABX464-102) and 248 patients have received ABX464 50mg for more than 6 
months.  
ABX464 was rapidly absorbed in healthy volunteers, HIV and UC patients with a Cmax observed approximately 
1.5 to 2.9 hours after dosing. Exposure to ABX464 was comparable in all subjects receiving ABX464 at a given 
dose. PK of ABX464 were linear in the dose range 50-150mg. After repeated administrations of ABX464, an initial 
decrease in ABX464 AUC was observed and steady state was reached after 4 weeks of treatment.  
ABX464 was rapidly metabolised to ABX464-N-Glu. ABX464-N-Glu had a much longer half-life compared to 
ABX464 (about 100 hours) largely contributing to the high exposures observed.  
Food increased ABX464 exposure at least 2.8-fold while exposure to the metabolite was comparable in fed or 
fasted conditions. 
Clinical Efficacy 
Completed and ongoing studies with ABX464 in UC are:  
• 
Phase 2a program with an 8-week induction (ABX464-101; completed) and a 4-year maintenance 
(ABX464-102; ongoing; 52-week interim analysis completed) studies 
• 
Phase 2b program including the 16-week induction (ABX464-103; completed) and an open-label 
extension (ABX464-104; ongoing) studies 
ABX464-103 was a randomized, double-blind and placebo-controlled phase 2b induction study and was 
conducted from 95 centres in 16 countries. It had three once-daily oral ABX464 treatment groups (25mg, 50mg 
and 100mg) and one placebo group. 254 patients with moderate to severe active ulcerative colitis were enrolled 
into the trial. 50% of these patients had inadequate response, loss of response, or intolerance to tumor necrosis 
factor alpha (TNF-α) inhibitors, vedolizumab, other biologics and/or JAK inhibitors treatments while the other 
50% were refractory to conventional treatments. Endoscopies were read centrally and blinded by independent 
reviewers. Electronic patient diaries were used to promote the reliability of the collection of stool frequency, 
rectal bleedings and other patient reported outcomes. Gender, clinical, biological and endoscopic parameters 
were well distributed across placebo and treatment groups at enrolment time. The primary endpoint, i.e. the 
reduction of the modified Mayo Score from baseline after 8 weeks of treatment was statistically significant for 
all active treatment groups. ABX464-103 study was completed in April 2021 (LPLV = 16 April 2021). 
 
 

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Table 01  
Primary and secondary efficacy endpoints in ABX464-103 study 
 
 
ABX464 was shown to be effective in patients refractory to conventional treatments and, importantly, also in 
patients with inadequate response, loss of response, or intolerance to biologics and/or JAK inhibitors. These 
efficacy results warrant the continuation of the development of ABX464 in UC indication. 
97.7% of all patients who completed the phase 2b induction study (ABX464-103), irrespective of treatments or 
treatment outcome during the induction study, enrolled into this subsequent open-label maintenance study to 
evaluate the long-term safety and efficacy profile of ABX464 for up to two years.  
Clinical Safety 
During non-clinical studies, the main clinical signs observed in non-clinical studies for ABX464 consisted of, 
ptyalism and bodyweight loss which was dose proportional and severe in some cases. the main target organs 
affected were the gastro-intestinal tract and liver with the main macroscopic findings observed as dark foci in 
the glandular mucosa of stomach, adverse altered cell foci and bile duct hyperplasia in the liver, adverse 
erosion/ulcer in the forestomach, centrilobular hepatocellular degeneration/necrosis and liver necrosis. Some 
degree of anemia was found in the 9-month marmoset study with ABX464-N-Glu. Immunosuppression has been 
observed in a 9-month study with direct dosing of ABX464-N-Glu in cynomolgus monkeys. Two cases of cardiac 
fibrosis, likely associated with the Marmoset Wasting Syndrome, have been observed in a 9-month study with 
marmoset monkeys exposed to high doses of ABX464-N-Glu. 
Week 8 top-line results  
(ITT1 population / N= 252)  
Placebo 
25mg 
50mg 
100mg 
Primary Endpoint  
Modified Mayo Score  
Mean change from baseline  
All patients  
-1.9 
-3.1 * 
-3.2 * 
-2.9 * 
Bio exposed 
-1.0 
-2.8 * 
-2.9 * 
-2.8* 
*p-values of <0.05 versus placebo for all dose groups (ANCOVA)  
Key Secondary Endpoints (not powered to show statistical significance)  
Endoscopic Improvementa,d 
All patients  
8 (13.6%) 
20 (34.5%) * 
21 (39.6%) * 
24 (44.4%) * 
Bio exposed 
1 (3.7%) 
8 (28.6%) * 
7 (30.4%) * 
8 (26.6%) * 
*p-values of <0.05 versus placebo for all dose groups using a likelihood ratio chi-square test  
Clinical Remission b, d 
All patients  
8 (12.5%) 
17 (27.9%) * 
11 (17.5%) 
16 (25.0%) 
Bio exposed  
1 (3.2%)  
6 (20.0%) *  
2 (6.7%)  
6 (18.8%) *  
*p-values of <0.05 versus placebo using a likelihood ratio chi-square test but not according to the predefined Mantel-
Haenszel Chi Square test (p<0.1)  
Clinical Response c, d  
All patients  
23 (35.9%)  
40 (65.6%) *  
38 (60.3%) *  
35 (54.7%) *  
Bio exposed 
5 (16.1%)  
17 (56.6%) *  
13 (43.3%) *  
15 (46.8%) *  
*p-values of <0.05 versus placebo using a likelihood ratio chi-square test  
Fecal Calprotectin (μg/g)  
Mean change from baseline  
All patients  
-1027.7  
-2192.8 **  
-2316.8 **  
-2280.9 **  
**p-values of <0.01 versus placebo (MMRM) 
1 = Intent-to-treat patient population. Drop-out patients were considered as failure for all binary endpoints. Nearest neighbor imputation 
(as defined in the Statistical Analysis Plan) was used for missing values at week 8 and applied to MMS, clinical remission, and clinical 
response. Endoscopic improvement rates are presented without imputation (data available at time point). 
a = Endoscopic improvement is defined as endoscopic subscore ≤1.    
b = Clinical remission (per Modified Mayo Score) is defined as stool frequency subscore (SFS) ≤1, rectal bleeding subscore (RBS) of 0 and 
endoscopic subscore ≤1. 
c = Clinical response (per Modified Mayo Score) is defined as a decrease from baseline in the Modified Mayo Score ≥2 points and ≥30% 
from baseline, plus a decrease in RBS ≥1 or an absolute RBS ≤1. 
d = Evidence of friability during endoscopy confers an endoscopic subscore of 2 or 3  

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As of 30 November 2021, 1023 subjects have received ABX464, according to various administration schedules, 
in all completed, and ongoing open-label clinical studies across all indications. Out of these 1023 subjects, 830 
subjects have been dosed with ABX464 50mg once daily (od) including 240 subjects for longer than 6 months 
with 197 for more than a year. In addition, 36 subjects have received ABX464 or placebo in the ongoing blinded 
clinical study (ABX464-921). All doses tested were well tolerated. 38 Serious Adverse Events were reported in all 
clinical studies, except COVID study (ABX464-401) which are reported separately in this IB. No fatalities were 
reported in non-COVID indication/population except one fatal case that was a road traffic accident and was 
unrelated to the study drug. 
Anticipated ABX464 adverse events (regardless of their severity) 
Frequent gastrointestinal symptoms such as abdominal pain, nausea, vomiting and diarrhea, as well as 
headaches, are described effects for ABX464, which are dose-dependent, with intensity going from mild to 
severe, occurring after treatment onset. 
Therefore, designated anticipated AEs are: 
• Headache 
• Nausea 
• Vomiting 
• Abdominal pain (abdominal pain or upper abdominal pain) 
• Diarrhea 
• Back pain 
Due to safety signals in nonclinical toxicology studies, the following events are monitored as adverse events of 
special interest in ongoing and future studies with ABX464: anemia, liver function tests abnormalities, serious 
grade 3 infections and opportunistic infections, malignancies including non-melanoma skin cancers and cardiac 
events, including biomarkers (blood levels of AST, troponin, CPK and NT-proBNP). 
The following events have been observed in clinical studies and are also monitored as adverse events of special 
interest in ongoing and future studies with ABX464: headaches, skin lesions plus lipase elevation and acute 
pancreatic disorders. 
Healthy volunteers and patients exposed to ABX464 will continue to be monitored with routine ECGs as part of 
the clinical studies. 
Overall, ABX464 is considered to be safe and clinical development is justified.  
For further information, please refer to the current Investigator’s Brochure. 
1.3. 
Rationale for the clinical study and study design 
Phase IIb study (ABX464-101) aimed at evaluating the efficacy and safety of ABX464 given at a fixed dose of 50mg 
once daily versus placebo in patients with moderate to severe active UC who have failed or are intolerant to 
immunomodulators, anti-TNFα or corticosteroids was conducted in Belgium, France, Germany, Austria, Poland, 
Hungary. 
32 patients were randomized (23 ABX464 patients/9 placebo). The principal study results are presented below. 
A strong efficacy signal was observed with ABX464 50 mg: 
• 
Clinical Remission rate of 35.0 % of ABX464 patients (Placebo = 11.1%) 
• 
Mucosal Healing rate of 50.0 % (p=0.03) of ABX464 patients (Placebo = 11.1%) 
• 
Clinical Response rate of 70.0 % of ABX464 patients (Placebo = 33.0%) 
Same results were also observed in Total and Partial Mayo Score, as depicted in the following graphs 

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Figure 3: Mean change in Total and Partial Mayo Score in ABX464-101 study 
At the end of the completed 2 months induction treatment study, 22 Patients (15 previously treated with ABX464 
and 7 on placebo) were enrolled into the open-label maintenance study with ABX464 50mg daily (ABX464-102) 
regardless of what treatment they had previously received. An interim analysis of this maintenance study was 
performed after all patients had completed at least 12 months dosing in the maintenance study, with a mean 
ABX464 treatment duration in the maintenance study of 422 days. 
The interim analysis used the Month 12 Per Protocol (M12 PP) dataset which included all subjects that had a 
Month 12 visit. Of the 22 subjects, 3 subjects were excluded from the M12 PP Set: 2 subjects from the ABX464 
induction group (one who withdrew due to lack of efficacy at M1 of the maintenance study and one who was 
lost to follow-up) and 1 subject from the placebo induction group (grade 2 headache at month 4), resulting in 19 
subjects analyzed in the efficacy M12 PP set at baseline. Of the nineteen subjects in the set, sixteen had had a 
Month 12 endoscopy performed which forms part of the Total Mayo score (TMS).  
Clinical remissions obtained at the end of the induction study were durable and the rates further improved during 
the maintenance phase, as additional subjects achieved clinical remission for 12 months treatment.  
All patients who had an endoscopy performed, had an endoscopic sub-score of 0 or 1. 12/16 patients were in 
clinical remission at month 12. 
Mean and median fecal calprotectin and CRP showed continued declines during the maintenance study, though 
the large variability and small patient numbers requires that the results should be interpreted with caution.  The 
measurement of miR124 relative gene expression by qPCR using whole blood samples was included in both 
ABX464-101 and -102.  A total of 19 patients were sampled on day 0, 28, 56 of ABX464-101 and on day 365 (while 
in ABX464-102). Statistically significant increases of miR124 expression were observed at all these time points. 
No severe or serious adverse reactions were reported. Most adverse events were of mild to moderate intensity. 
The efficacy and safety results of studies ABX464-101 and ABX464-103 warrant the continuation of the clinical 
development of ABX464 in this indication. 
 
 
 

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2. STUDY OBJECTIVES AND ENDPOINTS 
2.1. 
Primary Objective 
The primary objective of the study is to evaluate the long-term safety of ABX464 given at 50 mg once daily in 
subjects with Moderate to Severe Active Ulcerative Colitis. 
2.2. 
Secondary Objectives 
The secondary objectives are: 
• To evaluate the long-term effect of ABX464 on clinical and endoscopic remission in subjects with 
Moderate to Severe Active Ulcerative Colitis assessed by the MCS. 
• To evaluate the long-term effect of ABX464 on inflammatory markers (CRP, Calprotectin and ESR) 
• To evaluate the long-term of ABX464 on Quality of Life (QoL) measured by the SF-36 questionnaire in 
subjects with Moderate to Severe Active Ulcerative Colitis until M24. 
Echocardiography objective is: 
▪ To evaluate the effect of ABX464 on cardiac function as assessed through echocardiograms. 
 
2.3. 
Primary Endpoint 
The primary endpoint of this study is defined as the number of incidences of treatment-emergent adverse 
events in the ABX464 treated subjects. 
2.4. 
Secondary Endpoints 
The secondary endpoints of this study are: 
• The change from Day 0 in Total Mayo Score. 
• The change from Day 0 in Partial Mayo Score. 
• The time to UC worsening. 
• The change from Day 0 in fecal calprotectin, CRP levels and ESR. 
• The scores and changes from Day 0 in SF-36 Questionnaire scores. 
• The miR-124 expression at month 12, month 36 and month 48. 
• The number of incidences of treatment-emergent serious adverse events. 
• The number of incidences of treatment-emergent adverse events of special interest. 
• The number of incidences of adverse events leading to investigational product discontinuation. 
• The number of incidences of specific laboratory abnormalities. 
• 
Percentage of subjects reaching clinical remission at M12, M36, and M48. 
• 
Percentage of subjects reaching clinical response at M12, M36, and M48. 
• 
Percentage of subjects reaching endoscopic improvement at M12, M36, and M48. 
• 
Percentage of subjects reaching endoscopic remission at M12, M36, and M48. 
• 
Percentage of subjects reaching corticosteroid-free clinical remission at M12, M36, and M48. 
The echocardiography secondary endpoints [9] are: 
▪ Absolute (%) change-from-previous echocardiogram of Left ventricle Ejection Fraction (LVEF) as measured by 2-
dimensional echocardiography 
▪ Number of subjects with a clinically relevant reduction (change-from-previous echocardiogram) of LVEF, defined as 
by > 10% reduction (absolute percentage points) to a value < 50% 

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▪ Absolute (%) change in Global Longitudinal Strain (GLS) from-previous echocardiogram 
▪ Number of subjects with a relative percentage reduction in GLS by > 15% from the previous value 
▪ Number of subjects with a reduction of LVEF > 10% (absolute percentage points) to a value ≥ 50% with an 
accompanying fall in GLS > 15%  
▪ Number of subjects with reduction in LVEF by > 10% (absolute percentage points) to a value ≥ 50% 
▪ Changes from previous echocardiography of other echocardiographic parameters as described in a standard 
protocol, including 2-dimensional volumes, RV size and systolic function and valve function. 
 
 
 

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3. INVESTIGATIONAL PLAN 
3.1. 
Study design 
3.1.1. Design and methodology 
This study is an open-label study aiming at evaluating the long-term safety and the efficacy profile of ABX464 
given once a day (o.d) at 50 mg in subjects who have been previously enrolled in the ABX464-101 clinical study 
(induction study) and who are willing to continue their treatment. 
All subjects will receive ABX464 given at 50 mg o.d irrespective of their previous treatment received in the 
ABX464-101 study (i.e. ABX464 or Placebo). 
The actual treatment received by a subject throughout the previous study (ABX464-101) will not be known at the 
time the subjects enter this follow-up study. 
The enrolment in this follow-up study will be based on the willingness of the subject to carry on his/her 
participation and also based on investigator’s judgement. 
Subjects will be treated with ABX464 for an overall period of 48 months. Subjects will be followed up weekly 
during the first month, every two weeks during the second month and then on a monthly basis until M24, then 
quarterly from M24 to M48.  
At M48, depending on their clinical response, eligible patients willing to continue study treatment will be offered 
to take part into a long term follow up study (ABX464-108 study). ABX464-108 study is a separate study requiring 
health authorities and ethics committees’ approval. If patients are not eligible to pursue treatment in this long-
term follow-up study, they will be followed for 4 additional weeks for safety purposes before End of study Visit. 
3.1.2. 
Data Safety Monitoring Board – Independent Cardiovascular Safety 
Committee (ICVSC) 
An independent Data Safety Monitoring Board (DSMB), with expertise and experience in the pathology, and 
without direct involvement in the conduct of the trial, will be set up specifically to guarantee effective protection 
of subjects, ensure the ethical conduct of the trial, benefit/risk ratio of the trial, and to ensure the independent 
review of the scientific results during the trial and at the end of the trial. 
The DSMB will meet on a monthly basis until December 2019 and then quarterly from January 2020 onwards. 
Besides, the DSMB may recommend the early termination of the trial at any time if an unacceptable toxicity 
occurs. 
In addition, DSMB will be review all potential causally related Serious Adverse Events within 7 days of the initial 
report. 
The DSMB has only a consultative role; it will inform the sponsor who will decide whether the DSMB 
recommendation will be followed. A DSMB charter must be available upon submission of the trial (initial 
protocol) to the respective competent authorities. 
An Independent Cardiovascular Safety Committee (ICVSC), comprised of 3 cardiologists with experience from drug 
development, will be formed as detailed in the Charter. The ICVSC will be responsible for an on-going evaluation of 
cardiac adverse events of special interest (Cardiac AESIs), for treatment emergent echocardiographic findings, and for 
treatment emergent changes of cardiac safety biomarkers (as detailed above). The ICVSC will review cardiac adverse 
events on an on-going basis, meet regularly and provide recommendations to Sponsor and DSMB regarding study 
procedures and conduct. 
3.2. 
Duration of study participation 
Subjects will be enrolled in the present study at Day 0 and will be treated for a treatment overall duration of 48 
months. 
From ABX464 treatment stop onwards, subjects will be followed-up for one additional month. 
 
 

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4. STUDY POPULATION 
4.1. 
Number of Subjects/Centers 
These subjects were enrolled in some of the active sites of the induction study (ABX464-101). These sites are 
located in, Belgium, Poland and Hungary. 
4.2. 
Eligibility Criteria 
4.2.1. Inclusion Criteria 
A subject will be eligible for inclusion in this study only if ALL of the following criteria apply: 
▪ Subjects previously enrolled in the ABX464-101 clinical study who have completed the initial 2-month 
treatment phase; 
▪ Subjects able and willing to comply with study visits and procedures; 
▪ Subjects with hematological and biochemical laboratory parameters as follows at the D56 visit of the 
ABX464-101 study: 
o 
Hemoglobin > 9.0 g dL-1; 
o 
Absolute neutrophil count ≥ 750 mm-3; 
o 
Platelets ≥ 100,000 mm-3; 
o 
Total serum creatinine ≤ 1.3 x ULN (upper limit of normal); 
o 
Creatinine clearance > 50 mL min-1 by the Cockcroft-Gault equation; 
o 
Total serum bilirubin < 1.5 x ULN; 
o 
Alkaline phosphatase, AST (SGOT) and ALT (SGPT) < 1.5 x ULN; 
▪ Subjects should understand, sign and date the written voluntary informed consent form at the enrolment 
visit prior to any protocol-specific procedures being performed; 
▪ Females and males receiving the study treatment and their partners must agree to use a highly effective 
contraceptive method during the study and for 6 months after end of study or early termination. 
Contraception should be in place at least 3 months prior to study participation. Women must be surgically 
sterile or if of childbearing potential must use a highly effective contraceptive method. Women of 
childbearing potential (WOCBP) will enter the study after confirmed menstrual period and a negative 
pregnancy test. Highly effective methods of contraception include true abstinence, intrauterine device 
(IUD) or hormonal contraception aiming at inhibition of ovulation, intrauterine hormone releasing system, 
bilateral tubal ligation, vasectomized partner. True abstinence is defined when this is in line with the 
preferred and usual lifestyle of the patient. In each case of delayed menstrual period (over one month 
between menstruations) confirmation of absence of pregnancy is required. This recommendation also 
applies to WOCBP with an infrequent or irregular menstrual cycle. Female and male patients must not be 
planning pregnancy during the trial and for 6 months post completion of their participation in the trial. In 
addition, male participants should use condoms and should not donate sperm as long as contraception is 
required. 
4.2.2. Exclusion Criteria 
The following criterion should be checked at the time of screening. If this exclusion criterion applies, the subject 
will not be included in the study: 
▪ 
Any condition, which in the opinion of the investigator, could compromise the subject's safety or the 
adherence to the study protocol. 
 
 

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5. STUDY ASSESSMENTS AND PROCEDURES 
5.1. 
Study Flow Chart  
A detailed study flow chart (with all assessments) is displayed hereafter.  
 
(D56) 
D0 
D7 
D14 
D21 
D28 
D42 
Day56/M2 
Mx+1 
to 
M24 
M27 
to 
M45* 
M48 
EoS 
Time Window 
 
± 2 
days 
± 2 
days 
± 2 
days 
± 4 
days 
± 2 
days 
± 4 days 
± 4 
days 
± 14 
days 
± 14 
days 
28 days 
after 
ABX464 
Stop (± 
4 days)  
ABX464-101 D56 examinations 
X  
 
 
 
 
 
 
 
 
 
 
Obtained Inform Consent 
X  
 
 
 
 
 
 
 
 
 
 
Check of IN/EX Criteria 
X 
 
 
 
 
 
 
 
 
 
 
Physical Examination 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Body Weight (kg) 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Vital signs 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
ECG (12 lead) 
 
 
 
 
 
 
X 
At 
Month 
24 
X 
X 
X 
Blood Pregnancy test (WOCBP) 
 
 
 
 
X 
 
X 
X 
Xa 
Xa 
X 
Hematology + Biochemistry, 
including NT-proBNPb 
 
X 
X 
X 
X 
X 
X 
X 
Xb 
Xb 
Xb 
miR-124 blood sample 
(Paxgene®) 
 
 
 
 
 
 
 
At 
Month 
12 
At 
Month 
36  
At 
Month 
48 
 
Mayo score (Total or Partial) 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Faecal calprotectin  
 
 
 
 
X 
 
X 
X 
X 
X 
X 
Sigmoidoscopy 
 
 
 
 
As 
needed 
 
X 
At 
Month 
24 
At 
Month 
36  
At 
Month 
48 d 
 
 Cardiac ischemic 
disease/congestive heart failure 
medical/treatment history review 
 
 
 
 
 
 
 
 
X 
X 
 
Echocardiographyc 
 
 
 
 
 
 
 
 
X 
X 
 
SF-36 (Questionnaire) 
 
 
 
 
X 
 
X 
X 
 
 
 
ABX464 treatment dispensation 
X  
 
 
 
X 
 
X  
X 
X 
 
 
Adverse Events and CM 
recording  
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
* Visits are performed quarterly after M24 (at M27, M30, M33, M36, M39, M42, M45, M48).  
a Urine pregnancy tests will be provided to WOCBP to perform a pregnancy check every month (between onsite visits)  
b NT-proBNP blood levels only at Month 42 and 48 and at the End of Study Visit 
c Echocardiography at the earliest visit, then at Month 42 and 48 
d Local reading result of sigmoidoscopy need to be available on M48 visit to check eligibility to enter study ABX464-108 
5.2. 
Study conduct 
It is the investigator’s responsibility to ensure that all the assessments are carried out during each visit and that 
the intervals between visits/follow-ups are adhered to. 
5.2.1. Day 0 (D56 visit of the ABX464-101 study) 
The subject will be informed about the general aspects of the study and will sign the screening informed consent 
form. The subject number will be allocated once the subject will be created in the eCRF. Only when consent has 
been given may further study procedures be carried out. During Day 0 visit, the assessments planned as the D56 
Visit in the ABX464-101 study protocol should be performed.  
In addition, if the subject is eligible for the Follow-up study the following examination should be performed: 
• 
Signed informed consent form; 
• 
Inclusion/exclusion criteria will be verified globally; 
• 
ABX464 IMP dispensation; 
• 
Adverse Events and Concomitant Medications reporting. 
 

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5.2.2. Day 7, 14, 21, 42 visits (± 2 days) 
The following examinations/procedures should be performed: 
• 
Physical examination and vital signs; 
• 
Body weight; 
• 
Hematology & Biochemistry; 
• 
Partial Mayo Score; 
• 
Adverse Events and Concomitant Medications reporting; 
• 
Schedule next subject visits. 
5.2.3. Day 28, Day 56/M2, Mx+1 Visits (28 ± 4 days) until M24 
The following examinations/procedures should be performed: 
• 
SF-36 questionnaire (as the first visit procedure); 
• 
Physical examination and vital signs; 
• 
Body weight; 
• 
Hematology and Biochemistry including blood pregnancy test for all women of childbearing potential; 
• 
Faecal calprotectin dosage; 
• 
Sigmoidoscopy, mandatory only at D56 and at M24 
• 
12 leads ECG only at D56 and at M24;  
• 
Blood sampling for miR-124 expression at month 12 only: 
• 
Partial or Total Mayo Score; 
• 
ABX464 IMP dispensation 
• 
Adverse Events and Concomitant Medications reporting; 
• 
Schedule next subject visits. 
5.2.4. M27 until M45 (Calendar month ± 14 days)  
Visits are performed quarterly after M24. Only 7 visits should be performed at M27, M30, M33, M36, M39, M42, 
and M45. The following examinations/procedures should be performed: 
• 
Review of the subject’s medical history at the earliest opportunity to discontinue subjects with history 
of cardiac ischemic disease and/or congestive heart failure; If the patient needs to be discontinued, 
she/he will perform the End of Study Visit 4 weeks after last study drug intake. 
• 
Physical examination and vital signs; 
• 
Body weight; 
• 
Hematology and Biochemistry including blood pregnancy test for all women of childbearing potential 
and NT-proBNP (at Month 42 only); 
• 
Faecal calprotectin dosage; 
• 
12 leads ECG;  
• 
Blood sampling for miR-124 expression at month 36 only 
• 
Partial Mayo Score; 
• 
Total mayo score (only at M36); 
• 
ABX464 IMP dispensation; 
• 
Adverse Events and Concomitant Medications reporting; 
• 
Sigmoidoscopy, mandatory at M36; 
• 
Echocardiography at the earliest visit, and at M42; 

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• 
Schedule next subject visits. 
5.2.5. M48 (Calendar month ± 14 days)  
Visit M48 is the last visit in this study before entering the long-term follow-up study ABX464-108. If the patient 
is not eligible to enter this ABX464-108 study, she/he will perform the End of Study Visit (EoS) 4 weeks after last 
study drug intake. 
The following examinations/procedures should be performed: 
• 
Physical examination and vital signs; 
• 
Body weight; 
• 
Hematology and Biochemistry including blood pregnancy test for all women of childbearing potential 
and NT-proBNP; 
• 
Faecal calprotectin dosage; 
• 
12 leads ECG;  
• 
Blood sampling for miR-124 expression  
• 
Partial Mayo Score; 
• 
Total mayo score; 
• 
Adverse Events and Concomitant Medications reporting; 
• 
Sigmoidoscopy, mandatory; 
• 
Echocardiography 
• 
Schedule the EoS visit (if patient doesn’t enter the study ABX464-108) 
Nota bene: 
➢ The last treatment intake in study ABX464-102 should be the day before this visit M48. 
➢ The local reading result of sigmoidoscopy need to be available on M48 visit to check eligibility to 
enter study ABX464-108.The sigmoidoscopy can be performed within 14 days before the visit but 
not after the visit. If the sigmoidoscopy results (local reading) are not available on M48, the patient 
will be considered not eligible to enter the ABX464-108 study and will performed the end of study 
visit 28 days (+4 days) after M48. 
5.2.6. 
End of Study Visits 
This EoS visit should be performed 28 days (+4 days) after the last study treatment dosing, or if a subject meets 
a discontinuation criterion before. From the last dosing day, subjects will be treated according to standard of 
care.  
Following examinations/procedures should be performed: 
• 
Physical examination and vital signs; 
• 
Body weight; 
• 
Hematology and Biochemistry including blood pregnancy test for all women of childbearing potential 
and NT-proBNP; 
• 
Partial Mayo Score; 
• 
12 leads ECG;  
• 
Faecal calprotectin dosage; 
• 
Adverse Events and Concomitant Medications reporting. 
 

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NB: In case of premature discontinuation occurring during the treatment phase the above examinations should 
be performed as an End of Study Visit 4 weeks after treatment interruption. 
After the end of study visit, patients will be treated according to the local standard of care. 
5.3. 
Detail of the study assessments  
5.3.1. Echocardiography 
Since enrolment is completed at the time of this amendment, drug-free baseline measurements are not 
available.  
All patients ongoing in the study have already undergone Month 36 visit. Therefore, an echocardiography will be 
performed at the earliest visit and then at Month 42 and Month 48. Echocardiography will be performed locally. 
Procedures will be standardized for optimized video acquisition at clinical sites. Sites will receive an 
Echocardiography Manual that includes detailed instructions regarding image acquisition. 
Two-dimensional echocardiography measurements will be assessed during the study. The following standard 
parameters - pertinent to the assessment of changes in cardiac function will be assessed: 
▪ 
Left Ventricular Ejection Fraction (LVEF%) 
▪ 
Left Ventricular end systolic/end diastolic volumes 
▪ 
Left Ventricular septal/posterior wall thickness 
▪ 
Left Ventricular Mass/Mass indexed 
▪ 
Left Ventricular Global Longitudinal Strain (GLS) 
▪ 
Left Atrial volume 
▪ 
Doppler assessment (Mitral E/A ratio, Stroke Volume, Cardiac Output, Tissue Doppler Imaging) 
▪ 
Valvular assessment for regurgitation/stenosis 
▪ 
Right ventricular size 
Specific attention will be brought to potential changes from previous assessment in LVEF and GLS. All 
echocardiographic parameters will be presented descriptively and will be reviewed by the Independent 
Cardiovascular Safety Committee (ICVSC). 
5.3.2. Cardiac ischemic disease/congestive heart failure) medical / treatment 
history review 
• A retrospective review of medical history to search for cardiac ischemic disease and/or congestive heart 
failure will be done at the next possible visit of the subject as enrolment is finished at the time of this 
amendment. Patients with a history of or treated for cardiac ischemic disease and/or congestive heart failure 
will have to be discontinued from the study. If the patient needs to be discontinued, she/he will perform the 
End of Study Visit 4 weeks after last study drug administration and will then be treated according to the 
standard of care upon study treatment interruption. 
5.3.3. Physical Examination and Vital Signs 
A routine physical examination (including body weight) will be done at each study visit. Physical examinations 
will cover eyes, ears, nose, throat, lungs/thorax, heart/cardiovascular system, abdomen, skin and mucosae, 
nervous system, lymph nodes, musculo-skeletal system, and, if applicable, others. Any new clinically relevant 
finding compared to baseline must be documented as adverse event. 
Measurements of vital signs will be done at each visit (Blood pressure, Heart Rate, Body temperature). The 
subject should rest supine for at least 10 minutes prior to measurements. The measurements can be performed 
either in sitting or supine position of the subject. The right or left arm may be used. However, the position and 
the arm used for measurement should be kept constant throughout the trial for an individual subject.  

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The investigator should ensure that each parameter outside the normal range is assessed for clinical significance. 
For any deviation assessed clinically significant, the investigator has to document the change as an adverse event 
(AE) in the eCRF.  
In addition, it is at the discretion of the investigator to document any change or trend over time in vital signs as 
an AE if he considers the change to be clinically significant, even if the absolute value is within the alert limit or 
reference range. 
5.3.4. Pregnancy 
For all female subjects of childbearing potential, a blood pregnancy test (beta human chorionic gonadotropin 
[HCG]) will be each month and quarterly after Month 24. From Month 24 onwards, monthly urine pregnancy test 
will be provided to WOCBP to check for pregnancy between on-site visits. In case of positive pregnancy testing, 
detailed procedures can be found in section 8.4.2. 
5.3.5. ECG 
Electrocardiograms have to be done at Day 56, quarterly from M24 to M48 and at EoS visits. At least a 12-lead 
ECG with recordings of at least 6 action potentials in lead II (paper speed 25mm/s, amplitude 10mm/mV) has to 
be done in a resting position. Prior to the recording the subject should be at rest for at least five minutes. Resting 
ECG should be performed before any examinations. 
The ECG printout will be reviewed by the investigator and a signed and dated copy of the ECG will be attached 
to the medical file. The original ECG printouts are considered as source data and should be stored at site. In case 
thermal paper is used, a copy of the original ECG must be kept as well. All abnormal findings must be documented 
in the CRF. Any clinically relevant findings compared to ECG done at the EoS visit of the previous study (ABX464-
101) must be documented as adverse events. 
5.3.6. miR-124 expression level determination 
ABX464 up-regulates miRNA in PBMCs, making of this micro-RNA a potentially useful biomarker for ABX464 
treatment monitoring. Determination of miRNA level in total blood will be performed at Month 12, Month 36 
and Month 48 in order to assess the sustainability of the up regulation observed during the induction study. 
Assays for miRNA determination will be conducted by a specialized central laboratory. 
Total blood in PAXgene® tubes will be used according to lab manual instructions. 
5.3.7. SF-36 questionnaire (SF-36) 
The SF-36 questionnaire is a self-administered questionnaire containing 36 items which takes about five minutes 
to complete. It measures health on eight multi-item dimensions, covering functional status, well-being, and 
overall evaluation of health. SF-36 will be filled in by the subjects on a monthly basis until M24 prior to any study 
procedures. 
5.3.8. Partial/Total Mayo Score 
The Total Mayo score is the most commonly used index in clinical trials and consists of 4 items: stool frequency, 
rectal bleeding, flexible sigmoidoscopic examination, and a physician global assessment of disease activity 
(Appendix#3). 
A non-invasive 9-point Mayo or partial Mayo Score (pMS) incorporates stool frequency, rectal bleeding, and the 
physician’s global assessment of disease activity. The partial Mayo Score has been found to correlate closely with 
the full Mayo score and to independently have strong discriminative and construct validity and responsiveness 
to change in disease activity. 
Modified Mayo Score (MMS) consists of 3 items: stool frequency, rectal bleeding, flexible sigmoidoscopic 
examination) and partial Modified Mayo Score (pMMS) consists of only 2 items: stool frequency and rectal 
bleeding. Either the Partial or the Total Mayo score will be completed at each subject visit by the Investigator. 
Partial modified or modified Mayo score will also be used in descriptive analysis and for efficacy evaluation. 

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5.3.9. Sigmoidoscopy 
A Sigmoidoscopy will be performed in all subjects at Day 56/M2, Month 24, Month 36, and Month 48 (i.e. Study 
procedure).  
In addition, monthly sigmoidoscopies could be performed if deemed necessary by the investigator (Until month 
24). In such a case, the endoscopy rating will be reported in the eCRF (Total MCS). 
Sigmoidoscopies procedures (or colonoscopies if applicable) at Month 24, Month 36, and Month 48 will be 
standardized for optimized video acquisition at clinical sites. Sigmoidoscopies should be performed according to 
the Central Imaging Management System Charter. Central Imaging Management System will be provided 
including a central image database. Once uploaded, video data will be analyzed for quality and resolution prior 
to independent review by an expert central reader. Study videos will be scored separately using the Mayo Clinic 
Score (excluding friability) for all time points by central readers.  
The local reading result of sigmoidoscopy need to be available on M48 visit to check eligibility to enter study 
ABX464-108. The sigmoidoscopy can be performed within 14 days before the visit but not after the visit. If the 
sigmoidoscopy results (local reading) are not available on M48, the patient will be considered not eligible to 
enter the ABX464-108 study and will performed the end of study visit 28 days (+4 days) after M48. 
5.3.10. Clinical remission, clinical response, and corticosteroid-free clinical 
remission 
The following remission and response will be assessed at M12, M24, M36 and M48: 
Clinical remission is achieved when all the following criteria are met in the components of the Mayo Score:  
• 
rectal bleeding sub-score = 0 
• 
central endoscopy sub-score <= 1 
• 
stool frequency sub-score <= 1. 
Clinical response is defined as: 
• 
reduction in Total Mayo Score of at least 2 points and >= 30 percent from baseline 
• 
with an accompanying decrease in rectal bleeding sub-score of >= 1 point or absolute rectal bleeding 
sub-score of <= 1 point. 
Corticosteroid-free clinical remission is defined as clinical remission at M12, M24, M36 and M48, and 
concomitant corticosteroid free for ≥ 12 weeks prior to these timepoints among patients with clinical remission 
after 8 weeks of induction treatment (at baseline of ABX464-102 study). 
5.3.11. 
Endoscopic improvement and endoscopic remission 
Endoscopic improvement is achieved if the Mayo central endoscopic sub-score is 0 or 1.  
Endoscopic remission is defined as Mayo central endoscopic sub-score = 0.  
5.3.12. 
Hematology and biochemistry 
For hematology and biochemistry local laboratory will be used. All lab dosages will be done locally. 
Any hematology and biochemistry safety sample (Total bilirubin, AST/ALT, Alkaline phosphatase, Lipase INR, 
Prothrombin, high-sensitivity (hs) Troponin I & T, CPK and NT-proBNP) that does not have a result reported at 
any visit must be repeated (e.g. if sample is hemolyzed). The sample should be repeated as soon as possible (and 
recorded as an unscheduled visit in the eCRF). 
Each laboratory value that is outside of the institution’s normal range will be identified. The investigator will be 
responsible for assessing the clinical significance of laboratory abnormalities. If the investigator is uncertain 
about the clinical significance of a laboratory abnormality, he/she will consult with the Sponsor medical monitor. 
The investigator should follow any clinically significant laboratory abnormalities until resolution. 
Table  displays the clinical laboratory parameters that must be measured. 

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Table 2: Laboratory Tests 
HEMATOLOGY 
BIOCHEMISTRY 
STOOLS 
Hemoglobin 
Sodium 
Faecal calprotectin 
Hematocrit 
Potassium 
 
WBC 
Chloride 
 
Neutrophils 
Calcium 
 
Lymphocytes 
Phosphate 
 
Monocytes 
Glucose  
 
Eosinophils 
BUN or urea  
 
Basophils 
Creatinine  
 
Platelet count 
AST  
 
ESR 
ALT 
 
Fibrinogen 
GLDH 
 
Prothrombin time and/or INR 
Lipase 
 
 
Alkaline phosphatase 
 
 
gGT 
 
 
Total bilirubin  
 
 
Total protein  
 
 
Albumin  
 
 
LDH  
 
 
CRP 
 
 
CPK 
 
 
High-sensitive Troponin T and/or I 
 
 
NT-proBNP 
 
 
Amylase 
 
The indicative volumes drawn per study visit are presented in the following table. 
COLLECTION TUBE 
Hematology (Hemoglobin, Hematocrit, Red Cell Count, MCV, 
MCHC, Platelets, White cell count with diff.) 
2mL EDTA tube 
Fibrinogen and Prothrombin Time and/or INR 
4,5 mL Na-citrate tube 
NT-proBNP 
2mL K2 EDTA tube 
Biochemistry panel incl CRP, Serum Pregn. and hs Troponin 
(Iand/orT) 
3.5mL serum gel tube 
miR-124 determination at M12, M36, M48 only 
5mL of total blood (PAXgene tube) 
ESR  
5mL ESR tube 
 
 

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6. INVESTIGATIONAL PRODUCT(S) 
All investigational products to be used in this study have been manufactured, packaged and labelled by contract 
manufacturers for ABIVAX, according to GMP standards and are supplied to investigators free of charge. 
6.1. 
Description of investigational treatment 
The study treatment that will be administrated to subjects enrolled in this follow-up study consists of capsules 
containing ABX464 given orally once daily. 
6.2. 
Description of investigational Product 
6.2.1. Active investigational product (ABX464) 
The ABX464 investigational medicinal product (IMP) is a hard gelatin capsule intended for oral administration. 
For the proposed clinical trial, the IMP consists of size 01 capsules containing 50 mg of ABX464 drug substance 
in the form of granulate prepared with a number of common excipients (microcrystalline cellulose, 
polyvinylpyrrolidone, magnesium stearate and colloidal silica). It is supplied in high-density polyethylene bottles 
closed with high-density screw caps. 
ABX464 will be manufactured by:  
DELPHARM Lille SAS 
Parc d’activité Roubaix Est 
22, rue de Toufflers 
CS 50070 
59 452 Lys-Lez-Lannoy France 
Primary packaging labelling as well as Qualified Person release of the IMP are performed at the following site: 
CREAPHARM CLINICAL SUPPLIES (previously SODIA) 
Avenue Robert Schuman 
51 100 REIMS 
The study drug should not be stored above 30°C (86°F) and should not be frozen or refrigerated. 
6.3. 
Administration and Dosing 
6.3.1. Administration of the investigational product 
Subjects will be dosed with a daily dose of 50 mg that is 1 capsule every day. 
Subjects will be orally dosed in fed condition (regular breakfast) with a cup of water. 
A subject diary, in which the subject should report the number of capsules taken and the intake time, will be 
given to the subject at baseline. Moreover, this diary will enable the subject to report also potential discomfort 
or side effects s/he could experience. 
The last study treatment intake should be the day before M48 visit. 
6.3.2. Guidelines for treatment postponement and dose modifications 
No intra-subject dose escalation/dose adjustment are allowed.  
6.4. 
Method of Assigning Subjects to Treatment Arms 
All subjects will be assigned a unique and incremental subject Identification (ID) number (i.e. the same than the 
one used in the ABX464-101 study). Subject IDs will be unique (i.e. reallocation of the ID will not be permitted). 
The format will be a seven-digit number as follows: ABX-country/site number (4 digits) – subject number (3 

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digits). The latter 3-digit subject number will be assigned according to the subject’s order of inclusion in the 
center. 
Study treatment dispensation will be performed at each study visit. In all cases, subject should return his/her 
used and unused bottles at each study visit for a compliance check.  
6.5. 
Packaging 
The IMP consists in hard gelatin, powder-filled capsules (size 01) containing 50 mg of ABX464, supplied in high-
density polyethylene bottles closed with high-density screw caps. 
6.6. 
Storage 
ABX464 will be shipped to the investigational site at ambient temperature. The study drug should not be stored 
above 30°C (86°F) and should not be frozen or refrigerated.  
The IMP should not be used beyond the expiration date. Drug supplies are to be stored in a secure, limited-access 
location under the storage conditions required by GCP/GMP guidelines. 
6.7. 
Product Accountability 
An accurate and current accounting of the dispensing and return of IMP(s) will be maintained on an ongoing 
basis by the pharmacist and a member of the study site staff in the Accountability Log and case report form and 
will be verified by the study’s monitor. 
6.8. 
Prior and Concomitant Medication 
6.8.1. Allowed concomitant treatment 
Mandatory and/or allowed Concomitant Medications are: 
▪ 
ABX464 once daily at 50 mg. 
▪ 
Oral 5-aminosalicylic acid at stable dose. 
▪ 
Immunosuppressants in the form of azathioprine, 6-mercaptopurine, or methotrexate at stable dose. 
▪ 
Antidiarrheals (e.g., loperamide, diphenoxylate with atropine) at stable dose. 
▪ 
COVID-19 vaccines are allowed. 
Potential other concomitant medications should be kept at constant dose during the course of the study and 
properly reported in the medical file of the subject and the eCRF. 
This information should include the name of the medication (international nonproprietary name), daily dosage, 
duration and indication. 
6.8.2. Prohibited concurrent medications 
The following drugs are prohibited during the course of the study.  
▪ 
Anti-tumor necrosis factor (TNF) therapies. 
▪ 
Vedolizumab. 
▪ 
JAK inhibitors. 
▪ 
Topical corticosteroids and topical 5-aminosalicylic acid preparations. 
▪ 
Cyclosporine and tacrolimus. 
▪ 
Drugs that could interact with ABX464 should be avoided especially the CYP1A2 inducers/inhibitors. The 
following CYP1A2 inducers/inhibitors are prohibited during the whole course of the study (ciprofloxacin, 

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enoxacin, fluvoxamine, montelukast, phenytoin, rifampicin, ritonavir, teriflunomide). Please refer to 
Appendix #1. 
The UGT1A9 inhibitors and OAT P1B1/P1B3 inhibitors/substrates that could interact with ABX464 and 
its metabolite ABX464-N-Glu should also be avoided. Please refer to Appendix #1. 
▪ 
Use of any investigational or non-registered product within 3 months preceding Day 0 except ABX464. 
 
 

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7. SUBJECT COMPLETION AND WITHDRAWAL 
7.1. 
Subject Completion 
Treatment duration with ABX464 is 48 months or earlier if one study discontinuation criterion is met (defined 
below).  
The subjects exiting the study must perform the Follow-up and End of Study (EoS) visits 4 weeks after last study 
drug intake. They will be then treated according to the standard of care upon study treatment interruption. 
7.2. 
Study discontinuation criteria 
Subjects who are not found eligible or not willing to enter the ABX464-108 study are not considered as prematurely 
discontinued as they have completed the scheduled treatment of ABX464-102 study. 
A subject can be withdrawn at any time from the study for the following reasons: 
Subject’s study discontinuation could occur for the following reasons: 
• 
Investigator’s decision; 
• 
An Adverse Event or an intercurrent condition that preclude continuation of treatment;  
o 
specifically, an increase ≥ 3.0 x ULN in liver transaminases (AST/SGOT and/or ALT/SGPT) or an 
increase ≥ 2.0 x ULN in Alkaline phosphatase or in total bilirubin requires close observation with 
repeating liver enzymes and serum bilirubin tests two times weekly and clinical investigation to 
understand the etiology of this elevation. Frequency of retesting can decrease to once a month if 
abnormality stabilizes after the initial two weeks of follow-up and if the patient is asymptomatic. 
Discontinuation of the study treatment should occur if: 
• 
 ALT or AST > 8xULN 
• 
ALT or AST > 5xULN for more than 2 weeks 
• 
ALT or AST > 3xULN and total bilirubin > 2xULN or INR>1.5 
• 
ALT or AST > 3xULN with appearance of fatigue, nausea, vomiting, right upper quadrant pain or 
tenderness, fever, rash, and/or eosinophilia (>5%); 
o 
Severe (grade 3 or higher) infection, a severe (grade 3 or higher) opportunistic infection, or sepsis; 
o 
Any cardiac AESI or condition diagnosed during the course of the study and assessed by the clinical 
adjudication committee as changing the risk/benefit balance for the subject; 
o 
New onset of acute pancreatitis; 
o 
Malignancies (including non-melanoma skin cancers); 
o 
Any relevant toxicity or negative change in the risk/benefit assessment leading to an unacceptable 
risk for the subject or any data deriving from other clinical trials or toxicological studies which 
negatively influence the risk/benefit assessment. This may be applicable but is not limited to the 
following cases: occurrence of AEs which character, severity or frequency is new in comparison to 
the existing risk profile, or clinically significant abnormal laboratory results, including new onset 
anemia (defined as a hemoglobin decrease >2 g/dL from baseline or hemoglobin <8 g/dL 
• 
Worsening of the UC defined as a 2-point increase in the pMMS, with pMMS ≥ 4 on 2 separate occasions 
7 day-apart and confirmed by an endoscopy sub score of 2 points or higher; subject who would experience 
a treatment failure during the study may be withdrawn at any time. S/he will have to be treated according to 
standard of care as soon as s/he is discontinued from study treatment because of study withdrawal; 
• 
Withdrawal of consent; 
• 
Pregnancy; 
• 
Patients included with a history of cardiac ischemic disease and/or congestive heart failure will be discontinued 
from the study, will perform the End of Study Visit 4 weeks after last study drug administration and will then 
be treated according to the standard of care upon study treatment interruption. 
• 
Administrative reasons from Sponsor. 

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7.3. 
Study Discontinuation 
All subjects, regardless of the completion or premature discontinuation, should perform the Follow-up and End 
of Study Visits according to the study flow-chart. 
 

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8. ADVERSE EVENTS (AE), ADVERSE EVENT OF SPECIAL 
INTEREST (AESI) AND SERIOUS ADVERSE EVENTS (SAE) 
The investigator is responsible for the detection and documentation of events meeting the criteria and definition 
of an AE, AESI or serious adverse event (SAE). During the study, in case of a safety evaluation, the investigator or 
site staff will be responsible for reporting AEs, AESIs and SAEs, as detailed in this section of the protocol.  
During the screening period, only adverse event related to the screening procedures will be collected. 
Any disease progression will not be reported in the eCRF as an adverse event, but will be documented in the 
efficacy section. 
8.1. 
Definition of an AE 
Any untoward medical occurrence in a subject or clinical investigation subject administered a pharmaceutical 
product and which does not necessarily have to have a causal relationship with this treatment. 
An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), 
symptom, or disease (new or exacerbated) temporally associated with the use of a medicinal product, whether 
or not considered related to the medicinal product. 
8.2. 
Definition of an AESI 
The following events will be considered AESI and must be reported to Intuvigilance (same procedure as SAE). 
Skin Lesions (regardless of its severity)  
A dermatologist consultation should be scheduled to evaluate the type of lesion, its severity and etiology. An 
anonymized medical report shall be provided.  
Headaches  
Headaches are frequently reported by patients dosed with ABX464. Abivax follows closely, by means of individual 
adapted questionnaire, provided in Appendix #4, this AE in specific situations (i.e. headache lasting longer than 72 
hours AND not resolved by standard painkillers).  
Anemia  
Some degree of anemia was found in the 9-month marmoset study with ABX464-N-Glu. Although it has not been 
reproduced clinically, Abivax performs surveillance for anemia by means of regular determination of hemoglobin and 
hematocrit levels. Anemia defined as Hb drop > 2 g/dL from baseline or Hb < 8g/dL will be reported as AESI. 
Hepatic enzymes  
ABX464 showed liver findings in some toxicological studies, hence attention is paid to identification of liver enzymes 
elevations in subjects. No human predictors of hepatoxicity for ABX464 or its metabolite, ABX464-N-Glu, have been 
identified. Based upon preclinical and clinical available data, a DILIsym evaluation of ABX464 was conducted and 
concluded that there was no risk of DILI in these patients. A signal detection analysis of ALT/AST changes in subjects 
treated with ABX464 did not reveal any meaningful variation of the mean ALT/AST measurement throughout 
treatment nor an increased incidence of any liver function tests (LFTs). Sporadic cases of isolated alkaline 
phosphatase increase have been reported in patients dosed with ABX464. 
A specific liver function monitoring plan is implemented in all clinical studies (see Section 5.3.10 and  Section 7.2) during 
the course of treatment and a measurement of LFTs 4 weeks after treatment interruption (during End of Study visit). 
The LFTs should, as per the clinical protocols, include at least the determination of the liver transaminases (ALT/AST), 
gamma-glutamyl transferase (GGT), alkaline phosphatase and total bilirubin. Specifically, an increase ≥ 3.0 x ULN in 
liver transaminases (AST/SGOT and/or ALT/SGPT) or an increase ≥ 2.0 x ULN in total bilirubin without initial 
findings of cholestasis (elevated alkaline phosphatase) will be reported as AESI. 
Severe (grade ≥ 3) infections and opportunistic infections  
Immunosuppression has been observed during the 9-month cynomolgus monkey study with ABX464-N-Glu dosed 
directly by oral gavage. Therefore, serious (grade 3) infections and opportunistic infections due to bacterial, 

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mycobacterial, invasive fungal, viral, or parasitic organisms (including aspergillosis, blastomycosis, candidiasis, 
coccidioidomycosis, histoplasmosis, legionellosis, listeriosis, pneumocystosis, and tuberculosis) will be reported as 
AESIs. Subjects will be monitored for the development of signs and symptoms of infection during treatment with 
ABX464. ABX464 will be discontinued if a subject develops a severe (grade 3 or higher) infection, a severe (grade 3 or 
higher) opportunistic infection, or sepsis. 
Acute pancreatic adverse events 
Cases of transient increase in lipase serum levels have been observed in ABX464 clinical studies in ulcerative colitis 
patients as well as in patients with COVID-19 infection (blinded placebo/ABX464 treatment). Therefore, lipase and 
amylase will be monitored in the clinical studies. An elevation of serum lipase and/or amylase at least three times 
greater than the upper limit of normal will be reported as AESI and a workup for a diagnosis of pancreatitis will be 
performed according to the Atlanta criteria for the definition of acute pancreatitis. 
Definition of diagnosis of acute pancreatitis [10] 
The diagnosis of acute pancreatitis requires two of the following three features:  
• 
Abdominal pain consistent with acute pancreatitis (acute onset of a persistent, severe, epigastric pain often 
radiating to the back);  
• 
Serum lipase activity (or amylase activity) at least three times greater than the upper limit of normal; and  
• 
Characteristic findings of acute pancreatitis on contrast-enhanced computed tomography (CECT) and less 
commonly magnetic resonance imaging or transabdominal ultrasonography.  
If abdominal pain suggests strongly that acute pancreatitis is present, but the serum amylase and/or lipase activity is 
less than three times the upper limit of normal, as may be the case with delayed presentation, imaging will be required 
to confirm the diagnosis. The CECT will be planned and performed locally in that case.  
If the diagnosis of acute pancreatitis is established by abdominal pain and by increases in the serum pancreatic enzyme 
activities, a CECT is not usually required for diagnosis in the emergency room or on admission to the hospital. 
Malignancies including Non-Melanoma Skin Cancers 
Despite a lack/paucity of reported events in non-clinical and clinical trials, a potential impact on both innate and 
adaptive immune responses and the novel mechanism of action, could be a concern with regards to malignancies, 
mainly in the long-term. Therefore, all malignancies including non-melanoma skin cancers will be reported as an AESI.  
Cardiac Fibrosis: 
Two cases of cardiac fibrosis, likely associated with the marmoset wasting syndrome [11] , have been observed in a 9-
month study with marmoset monkeys exposed to high doses of ABX464-N-Glucuronide. These findings were 
considered to be spontaneous. A review of the safety database for ABX464 has revealed no changes in troponin level 
compared with placebo or any increased reporting of cardiovascular adverse events compared with placebo. However, 
the following cardiac monitoring will be performed in this study:  
Additional cardiac Laboratory monitoring procedures will include: 
1. 
Monitoring of AST, Troponin and creatinine phosphokinase (CPK) blood levels at each study visit, including 
baseline visit plus the End of Study Visit 
2. 
Monitoring of N-terminal pro b-type natriuretic peptide (NT-proBNP) blood levels every 6 months plus at 
the End of Study Visit.  
A relative change of more than 20% from baseline values in cardiac laboratory parameters will be reported as an 
AESI. 
Two-dimensional echocardiography with local evaluation will be performed every 6 months. 
An independent Cardiovascular Safety Committee (ICVSC) will evaluate cardiac AESIs, treatment emergent 
echocardiographic findings, and treatment emergent changes of cardiac safety biomarkers (as detailed above). 
The following treatment emergent adverse events (TEAEs) will also be categorized as Cardiac AESI: 
 
Under the Cardiac SOC: 
▪ Aortic valve disease 
▪ Asystole 

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▪ Atrial fibrillation 
▪ Atrial flutter 
▪ 3rd degree AV block (AV block complete) 
▪ Cardiac arrest 
▪ Chest pain – cardiac 
▪ Heart failure 
▪ Left ventricular systolic dysfunction 
▪ Mitral valve disease 
▪ Mobitz (type) II atrioventricular block (type 2, 2nd degree AV block) 
▪ Myocardial infarction 
▪ Myocarditis 
▪ Pericardial effusion 
▪ Pericardial tamponade 
▪ Pericarditis 
▪ Pulmonary valve disease 
▪ Restrictive cardiomyopathy 
▪ Right ventricular dysfunction 
▪ Sick sinus syndrome 
▪ Tricuspid valve disease 
▪ Ventricular fibrillation 
▪ Ventricular tachycardia 
8.3. 
Definition of a SAE 
A serious adverse event (experience) or reaction is any untoward medical occurrence that, at any dose: 
a) Results in death 
NOTE: Death is an outcome of an AE, and not an AE in itself. Event which led to death should be recorded with 
fatal outcome. 
b) Is life-threatening 
NOTE: The term 'life-threatening' in the definition of 'serious' refers to an event in which the subject was at risk 
of death at the time of the event. It does not refer to an event, which hypothetically might have caused death, if 
it were more severe. 
c) 
Requires hospitalization or prolongation of existing hospitalization 
NOTE: In general, hospitalization means that the subject has been detained (usually involving at least an 
overnight stay) at the hospital or emergency ward for observation and/or treatment that would not have been 
appropriate in the physician’s office or out-subject setting. Complications that occur during hospitalization are 
AEs. If a complication prolongs hospitalization or fulfills any other serious criteria, the event is serious. When in 
doubt as to whether “hospitalization” occurred, or was necessary, the AE should be considered serious. 
Hospitalization for elective treatment of a pre-existing condition that did not worsen after informed consent was 
given is not considered an AE. 
d) Results in persistent or significant disability/incapacity,  
NOTE: The term disability means a substantial disruption of a person’s ability to conduct normal life functions. 
This definition is not intended to include experiences of relatively minor medical significance such as 
uncomplicated headache, nausea, vomiting, diarrhea, influenza, and accidental trauma (e.g. sprained ankle) 
which may interfere or prevent everyday life functions but do not constitute a substantial disruption. 
e) Is a congenital anomaly/birth defect 
f) 
Is another medically important condition: This refers to an AE that may not be immediately life-
threatening or results in death or hospitalization but may jeopardize the subject or may require 
intervention to prevent one of the outcomes listed above. Based on medical and scientific judgment 
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If there is any doubt about whether or not an AE is serious, the investigator should contact the sponsor. 
8.3.1. Events and/or Outcomes Not Qualifying as SAEs 
Any hospitalization, or prolongation of hospitalization due to the circumstances listed below, will not be reported 
as SAE: 
• 
planned medical/surgical procedure; 
• 
planned medical/surgical admission (planned prior to entry into study, appropriate documentation 
required), for the disease under study; 
• 
Administrative or social reasons (e.g. lack of housing, economic inadequacy, care-giver respite, family 
circumstances).  
8.4. 
Events or Outcomes Qualifying as AEs or SAEs 
8.4.1. Clinical laboratory parameters  
Abnormal laboratory findings (e.g., clinical chemistry, hematology) or other abnormal assessments (e.g. vital 
signs) that are judged by the investigator as clinically significant will be recorded as AEs or SAEs if they meet the 
definitions of sections 8.1 and 8.2 respectively. Clinically significant abnormal laboratory findings or other 
abnormal assessments that are detected during the study or are present at informed consent and significantly 
worsen during the study will be reported as AEs or SAEs. Clinically significant abnormal laboratory findings or 
other abnormal assessments that are associated with the disease being studied, and are present at the start of 
the study but do not worsen, will not be reported as AEs or SAEs. However, if these findings or assessments are 
judged by the investigator to be more severe than expected considering the subject’s condition, then they may 
be reported as AEs or SAEs. 
8.4.2. Pregnancy report 
Subjects who become pregnant at any time will be immediately withdrawn from participation in the study. All 
appropriate withdrawal assessments may be performed at the discretion of the investigator. 
The investigator will collect pregnancy information on any woman subject or partner of a male subject, who 
becomes pregnant and their partner while participating in this study. The investigator will record pregnancy 
information on a specific pregnancy notification form and submit it to IntuVigilance Limited (see contact details 
in section 8.4) within 24 hours after knowledge of a subject's or partner’s pregnancy. The subject or partner will 
also be followed to determine the outcome of the pregnancy, be it full-term or prematurely terminated. 
Information on the status of the mother and child will be forwarded to ABIVAX or its designee. Follow-up will 
normally end 6 to 8 weeks following the estimated delivery date but could last up to one year after the delivery. 
While pregnancy itself is not considered to be an AE or SAE, any pregnancy complication or elective termination 
of a pregnancy for medical reasons will be recorded as an SAE. A spontaneous abortion is always considered to 
be an SAE and will be reported as such. 
The time period for collecting pregnancy information is identical to the time period for collecting AEs, as stated 
in Section 8.5, Time Period, Frequency, and Method of Detecting AEs and SAEs. Pregnancy information is 
collected from the signing of Pregnancy Follow up Inform Consent or Pregnant Partner Informed Consent to the 
end of the pregnancy follow-up. 
8.5. 
Time Period, and Frequency of Detecting AEs, AESIs and SAEs 
All AEs, AESIs and SAEs occurring from the time a subject consent to participate in the study until 4 weeks after 
he or she has completed or discontinued the investigational product must be recorded in the subject’s eCRF.  
Importantly, SAEs and AESIs will have to be reported, either by email or by Fax, to IntuVigilance Limited within 
24 hours of awareness of an SAE/AESI. 
Hotline phone: +44 800 689 4129 
Email Address: safety@intuvigilance.com 

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Fax number: +44 800 915 6753 
Legislative guidance requires also reporting any related SAEs to be reported after the subject finished the study 
if the investigator becomes aware of them. 
8.6. 
Recording AEs and SAEs 
Severity of AEs will be assessed according to CTC-AE Classification Version 4.0. 
Subjects will be asked to report all AEs as part of the procedures performed at each study visit. The site personnel 
will document all AEs in the subject’s medical record. All AEs subsequently must be recorded in the appropriate 
eCRF sections. 
The following points must be recorded for each event: 
• 
A description of the event in medical terms, not as reported by the subject; 
• 
Date of onset (start date); 
• 
Date of resolution (stop date); 
• 
The time of onset with respect to administering the investigational product; 
• 
The severity of the sign/symptom or clinically significant abnormal laboratory value according to 
CTC-AE Classification; 
• 
The causal relationship between the investigational product and the occurrence of each AE. This 
will be assessed by each investigator using clinical judgment. Alternative causes, such as natural 
history of the underlying diseases, concomitant medications, other risk factors and the temporal 
relationship of the event to the investigational product will have to be considered. The causality of 
all AEs should be assessed by the investigator with the following question: Is there a reasonable 
possibility that the AE may have been caused by the investigational product? And answered “NO” 
(if not related) and “YES” (if related); 
• 
Action taken regarding the investigational product:  
o 
No action; 
o 
Temporary discontinuation; 
o 
Permanent discontinuation; 
• 
Subject’s outcome: 
o 
Recovered without sequelae / resolved without sequelae; 
o 
Recovered with sequelae / resolved with sequelae; 
o 
Recovering/Resolving; 
o 
On-going; 
o 
Fatal (for SAEs only). 
 
If in any one subject, the same AE occurs on several occasions, the AE in question must be documented and 
assessed anew each time. 
8.7. 
Reporting of AESIs and SAEs to ABIVAX or its designee 
Throughout the study, the reporting of SAEs and AESIs to the Sponsor or its designee will be done through the 
SAE and AESI forms. 
It is the investigator’s responsibility to ensure that the SAE/AESI report is submitted to IntuVigilance Limited 
within 24 hours after knowledge of the event(s).  
The SAE/AESI forms or paper report forms should be completed as thoroughly as possible, with all the available 
details of the event and signed by the investigator or designee. An assessment of causality should always be 
provided at the time of the initial report. If the investigator or designee does not have all information regarding 
the SAE/AESI, he/she should not wait to receive additional information before completing the form and notifying 
IntuVigilance Limited.  

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Additional or follow-up information relating to the initial SAE report, will be requested, if necessary. Again, this 
information is to be completed and submitted through the SAE forms within 24 hours of receipt of the 
information.  
In the rare occasion when the facsimile equipment does not work and in the absence of, the investigator should 
notify IntuVigilance Limited by telephone within the given timeframe, and send a copy of the SAE report form by 
email. 
 

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8.8. 
Reporting of SAEs/ to Regulatory Authorities  
ABIVAX has a legal responsibility to notify, as appropriate, both the local regulatory authorities and other 
regulatory agencies about the safety of the investigational product. It is therefore important that the investigator 
notifies promptly ABIVAX or designee of any SAE, in order for legal obligations and ethical responsibilities towards 
other subjects to be met.  
In addition, the investigator or designee, will comply with the local regulatory requirements (when applicable) in 
reporting of SAEs to the ethics committee and, if required, to the relevant government authority. 
Safety reports on adverse events that are serious AND unexpected AND associated with the investigational 
product are prepared according to ABIVAX’s policy and applicable regulations and are forwarded to the 
investigators. These reports are filed with the investigator brochure or other appropriate study documentation. 
It is the Sponsor or its designee and/or investigator’s responsibility to notify the IRB or IEC of these reports, if 
applicable according to local requirements.  
 
 

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9. DATA ANALYSIS AND STATISTICAL CONSIDERATIONS 
A summary of the principal features of the statistical analysis of the data will be described here, in the statistical 
section of the protocol. A more technical and detailed elaboration of the principal features stated in the protocol 
will be given in the first version of the statistical analysis plan (SAP). 
Any amendments to the SAP will be clearly documented and signed prior to the final database lock including 
justifications and details of their potential impact on the interpretation of the study results. 
9.1. 
Statistical and Analytical Plans 
An interim analysis was performed at M12. 
The study analysis will be performed following database lock upon the completion of the last subject or upon its 
early discontinuation whichever occurs first.  
9.1.1. Protocol deviations 
Protocol deviations will be reviewed and classed as critical (immediate impact on patient safety or data integrity), 
major or minor during the data-review meeting. Major protocol deviations are defined as deviations liable to 
bias the evaluation of the main efficacy endpoint. The following deviations will be considered as major (non-
exhaustive list):  
• 
Non- compliance with the inclusion or exclusion criteria; 
• 
Non- compliance with the study treatment; 
• 
Intake of prohibited medication; 
• 
Noncompliance with time window. 
9.1.2. Definition of study analysis sets 
The following datasets will be defined and used for the analyses: 
• 
The Safety dataset (SAF population) is defined as those subjects included in the study, who have 
received at least one dose of the study treatment. 
• 
The Full Analysis dataset (FAS population) is defined as those subjects included in the study, who have 
received at least one dose of the study treatment, and who have at least one baseline data. 
• 
The Per Protocol dataset (PP population) is defined as those subjects of the FAS population without 
any major protocol deviation. 
9.1.3. Subjects/Subjects disposition 
The number and the percentages of subjects enrolled will be tabulated. The reason for subject exclusions from 
each of the populations will also be listed. In addition, the number of discontinued subjects with their reason for 
discontinuation will be tabulated. 
9.1.4. Demographic and other baseline characteristics 
Demographics and other baseline characteristics will be summarized by treatment arm. This analysis will be 
conducted on the FAS population. 
9.1.5. Treatment compliance 
Number of doses will be presented on the FAS population. 
 
 

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9.2. 
Efficacy Analysis 
All efficacy analysis will be conducted on both FAS population and PP population except if otherwise specified. 
Descriptive statistics will be presented by treatment arm and include: 
• 
Quantitative variables: mean, standard deviation, minimum and maximum, 95% confidence intervals, 
median and quartiles will be presented when considered relevant. Number of filled and missing values 
will also be presented. 
• 
Qualitative variables: count, percentage for each modality and 95% confidence intervals when relevant. 
Number of missing values will also be presented. 
9.3. 
Safety Analyses 
Adverse events will be coded using the standard dictionary (MedDRA) down to the lower level term (LLT). 
An overall summary table will be presented (Any adverse event, any treatment emergent adverse event (TEAE), 
any SAE, death, any grade 3 or higher adverse events from baseline to the end of Study. This analysis will be 
conducted on SAF population. 
Two periods will be defined for TEAE: 
• 
Any adverse event which occurs or worsens from first dosing to the last dosing day; 
• 
Any adverse event which occurs after the last dosing day. 
Adverse events will be described by primary system organ class and preferred term. Numbers and percentage of 
subjects, and number of occurrences of adverse event will be presented for: 
• 
TEAE; 
• 
Serious TEAE; 
• 
TEAE leading to drug discontinuation; 
• 
TEAE of grade 3 or 4; 
• 
TEAE for which relationship with the study drug is recorded as possible or probable 
• 
TEAE of special interest 
The assessment of safety will be based on the frequency of adverse events (with and without regard to causality) 
graded according to the CTC-AE Classification and also, the review of individual values for clinical laboratory data, 
vital signs and ECG focusing on the detection of abnormal values and PCSAs [potentially clinically significant 
abnormalities (PCSAs) determined upon investigator considerations]. 
All adverse events will be listed and the data will be tabulated by body system/organ class. Adverse event 
tabulations will include all treatment emergent adverse events, which will be further classified by severity, and 
relationship to treatment. 
Clinical laboratory parameters, echocardiography parameters, vital signs, and ECG will be summarized by using 
descriptive statistics (n, mean, SD, SEM, median, minimum and maximum). Number of subjects with at least one 
abnormal values will be tabulated (counts and percentages) for each parameter in summary shift tables. 
9.3.1. Clinical laboratory evaluation 
Descriptive statistics for laboratory parameters will be computed at each scheduled assessment. If relevant for 
some parameter, change from baseline will also be tabulated. In addition, shift tables from baseline will be 
presented. 
 

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9.4. 
Determination of Sample Size 
Not applicable 
 
 

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10. STUDY CONDUCT CONSIDERATION 
10.1. 
Regulatory and Ethical Considerations 
10.1.1. 
General Requirements 
The study will be conducted in compliance with the study protocol, ABIVAX / SIMBEC-ORION Standard Operating 
Procedures and in accordance with any local regulatory requirements, to ensure adherence to Good Clinical 
Practice (GCP) as described in the following documents: 
• 
ICH Harmonized Tripartite Guidelines for Good Clinical Practice (ICH E6 (R2). 
• 
US 21 Code of Federal Regulations dealing with clinical studies (including parts 50 and 56 concerning 
informed consent and IRB regulations). 
• 
Directive 2005/28/EC on the approximation of the laws, regulations and administrative provisions of the 
Member States relating to the implementation of good clinical practice in the conduct of clinical studies 
on medicinal products for human use and its guidance. 
• 
Declaration of Helsinki and its amendments. 
• 
EudraLex GMP guidelines Annex 13 related to shipment, storage and handling of investigational 
products. For the containment and countering against the spread of the COVID-19 virus (coronavirus 
disease 19), alternative delivery methods of the medicinal product(s) (IMP) from the Hospital Pharmacy 
to trial subjects may be arranged to guarantee the access to the IMP and the treatment continuity to 
the subjects; for example, by using couriers dedicated to delivering to the subject’s home or by 
delivering the medicinal product(s) to the caregiver/family members or delegates of the subject, if going 
to the clinical site is considered impossible or high risk for the subject. If a specialized courier is used for 
the transport of the medicinal product to the subject’s home, the use of personal data will be 
guaranteed according to the applicable regulations on Privacy. Suitable remote communication 
mechanisms with the trial subjects will be guaranteed and adequate documentation of the procedures 
put in place will be maintained and described in the appropriate procedure and documented in subjects’ 
medical source and Investigators’ Site Files.  
• 
Regulation (EU) 2016/679 of the European Parliament and of the Council of 27 April 2016 on the 
protection of natural persons with regard to the processing of personal data and on the free movement 
of such data. 
• 
EU Regulation 536/2014 of the European Parliament and of council, which introduces the Clinical Trials 
Information System (CTIS) that harmonizes the submission, assessment and supervision processes for 
clinical trials throughout Europe 
 
Upon signing the protocol, the investigator agrees to adhere to the instructions and procedures described in it 
and thereby to adhere to the principles of Good Clinical Practice that it conforms to. 
Written informed consents will be obtained for each subject before he or she can participate in the study.  
ABIVAX will obtain favorable opinion/approval to conduct the study from the appropriate regulatory agencies in 
accordance with any applicable country-specific regulatory requirements prior to a site initiating the study in 
that country. 
10.1.2. 
Independent Ethics Committee/Institutional Review Board 
Prior to the start of the study, the study protocol and amendments if applicable as well as other appropriate 
study-related documents will be submitted to an independent Institutional Review Board (IRB) or independent 
Ethics Committee (IEC), respectively. 
For each center it will be individually specified, who (investigator or sponsor) will be responsible for informing 
the IRB or IEC, respectively of any protocol amendments or new relevant information that require an ethical 
reconsideration of the study protocol. 
If the investigator is responsible for obtaining approval, he/she should also obtain a statement from the IRB or 
IEC, respectively that it is organized and operates according to GCP and applicable laws and regulations. 
 

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10.1.3. 
Subject Informed Consent 
It is the responsibility of the investigator to give each subject full and adequate verbal and written information 
regarding the aims, methods, anticipated benefits and potential hazards. The subject must be informed that 
participation is voluntary, and that they are free to withdraw from the study at any time without any 
disadvantages for their subsequent care. Although a subject is not obliged to give her/his reason(s) for 
withdrawing prematurely from the trial, the investigator should make a reasonable effort to ascertain the 
reason(s), while fully respecting the subject's rights. Written consent (signed and dated by the subject and the 
investigator) must be obtained prior to admission. The subject must be provided with a copy of the subject 
information and informed consent.  
The Investigator will be responsible for obtaining an ICF signed by the subject in accordance with ICH GCP 
guidelines to collect pregnancy information on any woman patient or partner of a male patient, who becomes 
pregnant while participating in this study. 
The data collected in this study will be processed anonymously at ABIVAX. Subjects should be informed about 
the purpose of the planned computer data processing and the publication of the data (e.g. at scientific meetings). 
The subject must give consent to the computer processing and to the publishing of anonymous data.  
The subject must be informed of and consent in writing that personal data relating to the trial may be subject to 
audits by Health Authorities and the sponsor. However, personal data will be kept strictly confidential and will 
not be made publicly available. 
10.1.4. 
Compensation to Subjects 
Insurance coverage will be provided for all subjects enrolled in the study from the time of the subject’s inclusion 
in the study (i.e. date of signing the ICF). The insurance coverage will be provided by the Sponsor and will be in 
line with GCP guidance and legal requirements, but also in accordance with local regulations. A confirmation of 
insurance and corresponding insurance conditions should be archived in the Investigator File. 
Besides, due to the cumbersome procedures related to the study (number of visits,…) subjects could be 
financially compensated by the Sponsor in accordance with the national regulations and the approval of the 
Ethics Committees. 
 
 

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11. STUDY MANAGEMENT 
11.1. 
Remote Data Entry 
An electronic case report form (eCRF) will be used to record all data required by the protocol. Remote Data Entry 
(RDE) will be used for data collection, i.e. the subject’s information pertaining to the study, will be entered into 
the eCRF via a computer at the investigational site. 
Prior to the start of the study, the investigator will complete a "Investigator site staff signature and task 
delegation log" form, showing the signatures and initials of any person who is authorized to make or change 
entries in the eCRF and any person authorized to electronically sign the eCRF. 
The eCRF used for this study is validated and fulfils the GCP ICH E6 (R2) requirements, European and FDA (21 CFR 
Part 11) regulations.  
Training sessions will be held for all the participants who will use this tool (e.g. investigators, ABIVAX staff and 
contract research organization [CRO] staff, including project managers, CRAs and data managers). 
Several supports are available to help all users with this tool including eCRF User Guide and five days a week / 
working hours helpdesk (support line). 
All of the information will be recorded through transcription from source documents into the eCRF by an 
authorized person.  
The investigator is responsible for the management and accuracy of the information in the eCRF. At each 
monitoring visit, the subject medical files should be at the clinical research associate's (CRA) disposal for review. 
11.2. 
Data management 
Data management will be outsourced to a Contract Research Organization (CRO). The data managers will issue 
electronic edit checks via EDC, and modification of the data will be permitted by the investigator to achieve 
accuracy with source documents and eliminate all inconsistencies in the data.  
The data will be reviewed for completeness and logical consistency. Automated validation programs will identify 
missing data, out of range data and other data inconsistencies at the time of entry. 
All new/updated information will be reviewed and verified by the appointed monitor.  
11.3. 
Data coding 
Adverse events, concomitant diseases, medical/surgical histories will be coded using the Medical Dictionary for 
Regulatory Activities (MedDRA). Concomitant medication will be coded using the WHO-DRUG dictionary. 
11.4. 
Study Monitoring 
The study will be conducted in accordance with the ICH Note for Guidance on GCP (ICH, Topic 6, 1996). The 
appointed monitor will contact the site prior to the start of the study to review with the site staff the protocol, 
study requirements, and their responsibilities to satisfy regulatory, ethical, and ABIVAX requirements. 
Throughout the study, the monitor will arrange visits to the study center at appropriate intervals to assess the 
progress of the study and review the completed eCRFs.  For the containment and countering against the spread 
of the COVID-19 virus (coronavirus disease 19), remote subjects visit and remote monitoring methods may be 
implemented, including the ability to phone or video call the trial site staff, for the purpose of source data 
verification. These methods will be described in the appropriate procedure and documented in subjects’ medical 
source and Investigators’ Site Files. 
During the monitoring visits, the monitor will: 
• 
Ensure that the safety and the rights of subjects are being protected; 
• 
Check that the data are authentic, accurate, and complete and discuss any inconsistencies; 

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• 
Ensure that all study materials are correctly stored and dispensed with particular emphasis to the 
investigational product; 
• 
Verify that the site staff and facilities continue to be adequate for the proper conduct of the study; 
• 
Ensure that the study is conducted in accordance with the currently approved protocol and any other 
study agreements, GCP, and all applicable regulatory requirements; 
• 
Help resolve any problems that may have arisen. 
In line with ICH GCP guidelines, monitoring will include verification of data entered in the CRF against the original 
subject records. Therefore, for the purpose of monitoring review, direct access to all study-related site and 
source documents is mandatory. Data items for which the eCRF will serve as the source document will be 
identified, agreed upon and documented. The investigator must also ensure provision of sufficient time, space 
and qualified personnel for the monitoring visits. 
11.5. 
Records Retention 
Following closure of the study, the investigator or the head of the medical institution (where applicable) must 
maintain all site study records, except for those required by local regulations to be maintained by someone else, 
in a safe and secure location. The records must be maintained to allow easy and timely retrieval, when needed 
(e.g., audit or inspection), and, whenever feasible, to allow any subsequent review of data in conjunction with 
assessment of the facility, supporting systems, and staff. 
ABIVAX will inform the investigator/institution of the required time period for retaining these records in order 
to be compliant with all applicable regulatory requirements. The minimum retention time will meet the strictest 
standard applicable to that study site, as dictated by ICH GCP E6 Section 4.9, any institutional requirements or 
local laws and regulations, or ABIVAX standards/procedures; otherwise, by default the retention period will be 
15 years. 
The investigator must notify ABIVAX of any changes in the archival arrangements, including, but not limited to, 
the following: archival at an off-site facility, transfer of ownership of the records in the event the investigator 
leaves the site. In addition, the investigator should seek the written approval of the Sponsor prior to disposing 
any of the archived records. 
11.6. 
Quality Assurance and Inspection by Authorities 
To ensure compliance with GCP and all applicable regulatory requirements, ABIVAX may conduct quality 
assurance audits. Regulatory agencies may also conduct a regulatory inspection of this study. Such 
audits/inspections can occur at any time during or after completion of the study. By signing the protocol 
agreement page, the investigator agrees to permit drug regulatory agencies and ABIVAX audits. If an audit or 
inspection occurs, the investigator and institution will allow the auditor/inspector direct access to all relevant 
documents and to allocate his/her time and the time of his/her staff to the auditor/inspector to discuss findings 
and any relevant issues. Items of particular interest in case of an audit are, but not limited to, the following: 
• 
IRB/IEC and regulatory authority approvals; 
• 
Informed consent forms of the subjects; 
• 
Approved study protocol and amendments and investigator brochure; 
• 
Treatment accountability; 
• 
Safety reporting; 
• 
Study file; 
• 
Study personnel; 
• 
Log of monitoring visits and monitoring process; 
• 
Medical records and other source documents; 
• 
Site facilities; 

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• 
Reports to the IRB/IEC and the sponsor; 
• 
Record retention. 
11.7. 
Study and Site Closure 
If the study is terminated prematurely or suspended for any reason, the investigator/institution should promptly 
inform the study subjects and should assure appropriate therapy and follow-up for the subjects 
ABIVAX reserves the right to temporarily suspend or prematurely discontinue this study, at any time for reasons 
including, but not limited to, safety or ethical issues or severe non-compliance. For multicenter studies, this can 
occur at one or more or at all sites. If such action is required, the Sponsor will discuss this with the investigator 
or the head of the medical institution (where applicable), including the reasons for taking such action, at that 
time. Advance notification will be provided to the site(s) when feasible, on the impending action prior to it taking 
effect. 
All investigators and/or medical institutions conducting the study will be informed in writing should the Sponsor 
decide to suspend or prematurely discontinue the study for safety reasons. The regulatory authorities will also 
be informed of the suspension or premature discontinuation of the study and the reason(s) for the action. If 
required by local regulations, the investigator must inform the IRB/IEC promptly and provide the reason for the 
suspension or premature discontinuation. 
Upon premature discontinuation of the study, the monitor will conduct site closure activities with the 
investigator or site staff, as appropriate, in accordance with applicable regulations, GCP, and ABIVAX procedures. 
All data must be returned to ABIVAX. Arrangements will be made for any unused investigational product based 
on the relevant ABIVAX procedures for the study. 
11.8. 
Study report and Publication 
Upon conclusion of the study, an integrated clinical and statistical study report will be written by the Sponsor in 
consultation with the Coordinating Investigator. This report will be based on the items detailed in this study 
protocol. When the clinical study report is completed, ABIVAX will provide the investigators with a full summary 
of the study results. The investigators are encouraged to share the summary results with the subjects, as 
appropriate. 
The first resulting publication will be a full publication of all data from all participating sites, coordinated by 
ABIVAX. Any secondary publications by the investigators (abstracts in journals, oral presentations etc.) will 
reference the original publication and will require pre-submission review by the Sponsor. Note that the Sponsor 
is entitled to delay any proposed secondary publication, in order to obtain patent protection, if required. 
The Coordinating Investigator as well as other members of the study committee will be authors on the first 
publication. The principal investigator of the trial will be the first author. Authorship for other investigators will 
be assigned on the basis of their recruitment contribution, as well as intellectual and administrative input. 
Ranking will be according to the number of subjects enrolled as well as contribution to the study conduct and 
preparation of final manuscript.  
11.9. 
Ownership and Confidentiality 
All information provided by ABIVAX and all data and information generated by the sites, as parts of the study 
(excluding the subjects’ medical records) are property of ABIVAX.  
All potential investigators must be aware of and agree in writing (confidentiality agreement) to the confidential 
nature of the information pertaining to this study. Furthermore, all information provided by ABIVAX and all data 
and information generated by the sites during the study must be kept confidential by the investigator and other 
site staff, and may not be used for any purpose other than conducting this study. 

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12. REFERENCES  
1. 
Ghosh S. Mitchell R. Results of the European Federation of Crohn's and Colitis Associations (EFCCA) subject survey: 
prevalence and impact on quality of life Gut  55 Suppl V 2006 A72. 
2. 
Kornbluth A, Sachar DB. Ulcerative colitis practice guidelines in adults (update): American College of 
Gastroenterology, Practice Parameters Committee. Am. J. Gastroenterol. 99(7), 1371–1385 (2004). 
3. 
Travis SPL, Stange EF, Lémann M et al. European evidence-based consensus on the management of ulcerative 
colitis: current management. J. Crohn's Colitis (2), 24–62 (2008). 
4. 
Truelove SC, Witts LJ. Cortisone in ulcerative colitis; final report on a therapeutic trial. Br. Med. J. 2(4947), 1041–
1048 (1955). 
5. 
Jess T, Riis L, Vind I et al. Changes in clinical characteristics, course, and prognosis of inflammatory bowel disease 
during the last 5 decades: a population-based study from Copenhagen, Denmark. Inflamm. Bowel Dis. 13(4), 481–
489 (2007). 
6. 
Sonnenberg A. Time trends of mortality from Crohn's disease and ulcerative colitis. Int. J. Epidemiol. 36(4), 890–
899 (2007). 
7. 
Leal, R. F., Planell, N., Kajekar, R., Lozano, J. J., Ordás, I., Dotti, I., Esteller, M., Masamunt, M. C., Parmar, H., Ricart, 
E., Panés, J., & Salas, A. (2015). Identification Of Inflammatory Mediators In Patients With Crohn’s Disease 
Unresponsive To Anti-Tnfα Therapy. Gut, 64(2), 233–242. Https://Doi.Org/10.1136/Gutjnl-2013-306518 
8. 
Yang, X. O., Panopoulos, A. D., Nurieva, R., Seon, H. C., Wang, D., Watowich, S. S., & Dong, C. (2007). Stat3 Regulates 
Cytokine-Mediated Generation Of Inflammatory Helper T Cells. Journal Of Biological Chemistry, 282(13), 9358–
9363. Https://Doi.Org/10.1074/Jbc.C600321200 
9. 
Dobson R, Ghosh AK, Ky B, et al. British Society for Echocardiography and British Cardio-Oncology Society guideline 
for transthoracic echocardiographic assessment of adult cancer patients receiving anthracyclines and/or 
trastuzumab. Echo Res Pract. 2021; 8: G1-g18. 
10. Banks et al (2012); Acute Pancreatitis Classification Working Group. Classification of acute pancreatitis--012: 
revision of the Atlanta classification and definitions by international consensus. Gut. 2013 Jan;62(1):102-11. doi: 
10.1136/gutjnl-2012-302779. Epub 2012 Oct 25. PMID: 23100216 
11. Cabana et al, (2018) identification of possible nutritional and stress risk factors in development of Marmoset 
Wasting Syndrom DOI: 10.1002/zoo.21398 
 
 
 

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13. APPENDICES 
Appendix 1: CYPIA2 inducers/inhibitors, OATB1B1/1B3 inhibitors and substrates, UGT1A9 
inhibitors  
CYP1A2 inducers/inhibitors (in bold: prohibited concomitant medications) 
Inhibitors: 
Artemisinin, Atazanavir, Ciprofloxacin, Enoxacin, Ethinyl Estradiol, Fluvoxamine, Mexiletine, Tacrine, 
Thiabendazole, Zileuton 
Inducers: 
Montelukast, Phenytoin, Rifampicin, Ritonavir, Teriflunomide 
 
OATB1B1/1B3 inhibitors and substrates (prohibited concomitant medications) 
Substrates: 
Asunaprevir, Atorvastatin, Atrasentan, Bosentan, Caspofungin, Cerivastatin, Daprevir, Docetaxel, 
Eluxadoline, Empagliflozin, Erythromycin, Fexofenadine, Fimasartan, Fluvastatin, Glecaprevir, Glyburide, 
Grazoprevir, Letermovir, Lopinavir, Lovastatin, Nateglinide, Nelfinavir, Olmesartan, Paritaprevir, 
Pitavastatin, Pravastatin, Repaglinide, Rosuvastatin, Simvastatin, Telmisartan, Torsemide, Voxilaprevir 
Inhibitors: 
Cyclosporine, Eltrombopag, Lapatinib, Lopinavir, Rifampicin, Ritonavir 
 
UGT1A9 inhibitors (prohibited concomitant medications) 
Inhibitors: 
Regorafenib, Fosphenytoin, Phenytoin, Eltrombopag, Mefenamic acid, Diflunisal, Niflumic acid, Sorafenib, 
Isavuconazole, Deferasirox, Morniflumat, Rifampicin 
 
 
 

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Appendix 2 : SF-36 Questionnaire (English Version) 
 

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Appendix 3: Mayo Score (Ulcerative Colitis) 
 
 
 
 
 

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Appendix 4: Follow-up Headache questionnaire 
 
 
 

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