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Dose-Ranging Phase 2b Study of ABX464 in Moderate to Severe Ulcerative Colitis

A Randomized, Double Blind, Placebo Controlled, Parallel Group, Multiple Dose, Induction Study to Evaluate the Safety, Tolerability and Optimal Dose of ABX464 Compared With Placebo in Patients With Moderate to Severe Ulcerative Colitis Who Have Inadequate Response, Loss of Response, or Intolerance With at Least One of the Following Agents: Immunosuppressant Treatment (i.e. Azathioprine, 6-mercaptopurine, Methotrexate), Tumor Necrosis Factor Alpha [TNF-α] Inhibitors, Vedolizumab, JAK Inhibitors and/or Corticosteroid Treatment

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03760003
Enrollment
355
Registered
2018-11-30
Start date
2019-08-13
Completion date
2021-04-16
Last updated
2025-11-28

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Ulcerative Colitis

Keywords

ABX464, Refractory patients, Phase 2b, Dose Ranging

Brief summary

Phase 2b study to evaluate the efficacy and the safety of 3 dose-levels of ABX464, administered daily in patients with moderate to severe Ulcerative Colitis.

Detailed description

This phase 2b study will evaluate the efficacy and the safety of 3 dose-levels of ABX464, administered daily in improving Modified Mayo Score (MMS) in patients with moderate to severe Ulcerative Colitis who have inadequate response, loss of response, or intolerance with at least one of the following agents: immunosuppressant treatment (i.e. azathioprine, 6-mercaptopurine, methotrexate), tumor necrosis factor alpha \[TNF-α\] inhibitors, vedolizumab, JAK inhibitors and/or corticosteroid treatment . Eligible patients will be randomized into 4 parallel intervention/treatment groups: 100mg q.d of ABX464, 50mg q.d of ABX464, 25mg q.d of ABX464, or matching placebo and will be treated for 16 weeks.

Interventions

DRUGABX464 100 mg

ABX464 100 mg (two capsules of ABX464 50 mg) once daily for 16 weeks

DRUGABX464 50 mg

ABX464 50 mg (one capsule of ABX464 50 mg + one capsule of placebo) once daily for 16 weeks

DRUGABX464 25 mg

ABX464 25 mg (one capsule of ABX464 25 mg + one capsule of placebo) once daily for 16 weeks

DRUGPlacebo

Two capsules of placebo once daily for 16 weeks

Sponsors

Abivax S.A.
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Intervention model description

Randomized, double blind, placebo controlled, parallel groups

Eligibility

Sex/Gender
ALL
Age
18 Years to 75 Years
Healthy volunteers
No

Inclusion criteria

* Men or women age 18 - 75 years; * Diagnosis of moderate to severe active UC (including ulcerative proctitis if proximal extension of disease occurs beyond 10 cm) confirmed by endoscopy and histology at least 12 Weeks prior to screening visit. Moderate to severe active UC defined by Modified Mayo Score (MMS) of 5 to 9 inclusive (on a scale of 0-9). Moderate to severe active UC should be confirmed at screening visit with a centrally read endoscopy sub-score of at least 2 (on a scale of 0-3); * Patients having either a documented inadequate response, no response, a loss of response, or an intolerance (defined as the occurrence of at least one Adverse Reaction leading to treatment discontinuation) to either immunosuppressant treatment (i.e., azathioprine, 6-mercaptopurine, methotrexate), tumor necrosis factor \[TNF\] inhibitors, vedolizumab, JAK inhibitors and/or corticosteroid treatment. Inadequate response, no response, loss of response is defined as: i. Active disease or relapse in spite of thiopurines or methotrexate given at an appropriate dose for at least 3 months (i.e. azathioprine 2-2.5 mg/kg/day or mercaptopurine 1-1.5 mg/kg/day in the absence of leukopenia), and/or ii. Active disease despite corticosteroids treatment (prednisolone up to 0.75 mg/kg/day) over a period of 4 Weeks, and/or iii. Active disease or relapse in spite of adequate treatment (as defined in the SmPC) with tumor necrosis factor \[TNF\] inhibitors or vedolizumab, and/or iv. Active disease or relapse in spite of adequate treatment with JAK inhibitors over a period of at least 6 Weeks. * Patients receiving oral corticosteroids must have been on a stable dose of prednisone or prednisone equivalent (≤20 mg/day) or on beclomethasone diproprionate (≤5mg/day) or on budesonide MMX (≤9 mg/day) for at least 2 Weeks prior to the screening visit; * Topical corticosteroids and topical 5-aminosalicylic acid preparations must have been withdrawn at least 2 Weeks prior to the screening visit; * Patients who are on oral 5-aminosalicylic acid must have been on a stable dose for at least 4 Weeks prior to the screening visit; * Patients who are receiving immunosuppressants in the form of azathioprine, 6-mercaptopurine, or methotrexate needed to be on a stable dose for at least 4 Weeks prior to screening visit. Patients taking methotrexate also are advised to take folic acid 1 mg/day (or equivalent) supplementation if there is no contraindication; * Patients on probiotics (e.g., Culturelle® \[Lactobacillus GG, i-Health, Inc.\], Saccharomyces boulardii) must be on stable doses for at least 2 Weeks prior to the screening visit; * Patients on antidiarrheals (e.g., loperamide, diphenoxylate with atropine) must be on stable doses for at least 2 Weeks prior to the screening visit; * Patients who have received tumor necrosis factor \[TNF\] inhibitors, vedolizumab or other biologics must have discontinued therapy at least 8 Weeks prior to the screening visit due to lack or insufficient efficacy or intolerance; * Patients previously treated with cyclosporine, tacrolimus or JAK inhibitors must have discontinued therapy at least 4 Weeks prior to the screening visit due to lack or insufficient efficacy or intolerance; * Patients previously treated with tube feeding, defined formula diets, or parenteral alimentation/nutrition must have discontinued treatment 3 Weeks before the screening visit and must be able to take, orally, appropriate amount of food (calories) and liquids to maintain body weight; * Patients with surveillance colonoscopy defined as per ECCO guidelines; * Patients with the following hematological and biochemical laboratory parameters obtained at screening: i. Hemoglobin \> 9.0 g dL-1; ii. Absolute neutrophil count ≥ 750 mm-3; iii. Platelets ≥ 100,000 mm-3; iv. Total serum creatinine ≤ 1.3 x ULN (upper limit of normal); v. Creatinine clearance \> 90 mL min-1 by the Cockcroft-Gault equation within 60 days prior to baseline; vi. Total serum bilirubin \< 1.5 x ULN; vii. Alkaline phosphatase, AST (SGOT) and ALT (SGPT) \< 2 x ULN; * Patients are able and willing to comply with study visits and procedures as per protocol; * Patients should understand, sign and date the written voluntary informed consent form at the screening visit prior to any protocol-specific procedures are performed; * Patients should be affiliated to a social security regimen (for French sites only); * Females and males receiving the study treatment (potentially in combination with immunosuppressant) 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 2 Weeks 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 not donate sperm as long as contraception is required.

Exclusion criteria

* Patients with Crohn's Disease (CD) or presence or history of fistula, indeterminate colitis (IC), infectious/ischemic colitis or microscopic colitis (lymphocytic and collagenous colitis); * History of toxic megacolon, abdominal abscess, symptomatic colonic stricture or stoma; history or imminent colectomy, colonic malignancy; * History or current evidence of colonic dysplasia or adenomatous colonic polyps. Patient with severe gastrointestinal complications; e.g., short bowel syndromes, recent or planned bowel surgery, Ileostomy and/or colostomy, recent bowel perforation; * History of more than one episode of herpes zoster or a history (single episode) of disseminated zoster; * Patients with active infections at screening such as infected abdominal abscess, Clostridium difficile (stool antigen and toxin required), CMV (positive IgM), TB and recent infectious hospitalization; * Patients previously treated with ABX464; * Acute, chronic or history of clinically relevant pulmonary, cardiovascular, hepatic, pancreatic or renal functional abnormality, encephalopathy, neuropathy or unstable CNS pathology such as seizure disorder, angina or cardiac arrhythmias, active malignancy or any other clinically significant medical problems as determined by physical examination and/or laboratory screening tests and/or medical history; * Acute, chronic or history of immunodeficiency or autoimmune disease; * History of malignancy excluding patients considered cured (5 years disease free survivors); * Serious illness requiring systemic treatment and/or hospitalization within 3 Weeks prior to baseline; * Pregnant or breast-feeding women; * Illicit drug or alcohol abuse or dependence; * Patients who received live vaccine 30 days or fewer before first dose of study treatment and/or who's planning to receive such a vaccine during the study duration; * Use of any investigational or non-registered product within 3 months or within 5 half-lives preceding baseline, whichever is longer and during the study; * Any condition, which in the opinion of the investigator, could compromise the patient's safety or adherence to the study protocol.

Design outcomes

Primary

MeasureTime frameDescription
Reduction From Baseline in Modified Mayo Score (MMS) at Week 8Week 8Reduction from baseline in Modified Mayo Score (MMS) MMS is a composite score of UC disease activity based on the following 3 subscores: 1. Stool frequency subscore (SFS), scored from 0 (normal number of stools) to 3 (5 or more stools more than normal). 2. Rectal bleeding subscore (RBS), scored from 0 (no blood seen) to 3 (blood alone passed). 3. Endoscopic subscore, scored from 0 (normal or inactive disease) to 3 (severe disease, spontaneous bleeding, ulceration). The overall MMS ranges from 0 to 9 where higher scores represent more severe disease.

Secondary

MeasureTime frameDescription
Number of Participants in Clinical Remission Per MMS at Week 8Week 8Number of participants who achieved clinical remission per Modified Mayo Score at Week 8 MMS is a composite score of UC disease activity based on the following 3 subscores: 1. Stool frequency subscore (SFS), scored from 0 (normal number of stools) to 3 (5 or more stools more than normal). 2. Rectal bleeding subscore (RBS), scored from 0 (no blood seen) to 3 (blood alone passed). 3. Endoscopic subscore, scored from 0 (normal or inactive disease) to 3 (severe disease, spontaneous bleeding, ulceration). The overall MMS ranges from 0 to 9 where higher scores represent more severe disease. Clinical remission is defined as SFS ≤ 1, RBS of 0, and endoscopic subscore ≤ 1 (modified to exclude friability)
Number of Participants in Clinical Remission Per MMS at Week 16Week 16Number of participants who achieved clinical remission per Modified Mayo Score at Week 16 MMS is a composite score of UC disease activity based on the following 3 subscores: 1. Stool frequency subscore (SFS), scored from 0 (normal number of stools) to 3 (5 or more stools more than normal). 2. Rectal bleeding subscore (RBS), scored from 0 (no blood seen) to 3 (blood alone passed). 3. Endoscopic subscore, scored from 0 (normal or inactive disease) to 3 (severe disease, spontaneous bleeding, ulceration). The overall MMS ranges from 0 to 9 where higher scores represent more severe disease. Clinical remission is defined as SFS ≤ 1, RBS of 0, and endoscopic subscore ≤ 1 (modified to exclude friability)
Number of Participants With Clinical Response at Week 8Week 8Clinical response is defined as a reduction in MMS of at least 2 points and greater than or equal to 30 percent from baseline with an accompanying decrease in rectal bleeding sub-score of greater than or equal to 1 point or absolute rectal bleeding sub-score of less than or equal to 1 point.
Number of Participants With Clinical Response at Week 16Week 16Clinical response is defined as a reduction in MMS of at least 2 points and greater than or equal to 30 percent from baseline with an accompanying decrease in rectal bleeding sub-score of greater than or equal to 1 point or absolute rectal bleeding sub-score of less than or equal to 1 point.
Number of Participants With Endoscopic Improvement at Week 8Week 8Endoscopic improvement is defined as an endoscopic subscore of 0 or 1 (excluding friability) Endoscopies were assessed by a blinded central reader and scored according to the following scale: 0 = Normal or inactive disease; 1. = Mild disease (erythema, decreased vascular pattern); 2. = Moderate disease (marked erythema, lack of vascular pattern, any friability, erosions); 3. = Severe disease (spontaneous bleeding, ulceration). A higher endoscopic score indicates more severe disease.
Number of Participants With Endoscopic Improvement at Week 16Week 16Endoscopic improvement is defined as an endoscopic subscore of 0 or 1 (excluding friability) Endoscopies were assessed by a blinded central reader and scored according to the following scale: 0 = Normal or inactive disease; 1. = Mild disease (erythema, decreased vascular pattern); 2. = Moderate disease (marked erythema, lack of vascular pattern, any friability, erosions); 3. = Severe disease (spontaneous bleeding, ulceration). A higher endoscopic score indicates more severe disease.
Number of Participants With Mucosal Healing at Week 8Week 8Mucosal healing is defined as endoscopic remission (overall mucosal appearance at endoscopy subscore=0) and histological remission (Geboes score \<2.0 based on rectal biopsy). The endoscopic subscore ranges from 0 (normal or inactive disease) to 3 (severe disease with spontaneous bleeding, ulceration). The Geboes histologic index includes seven histological features (architectural change, chronic inflammatory infiltrate, lamina propria neutrophils and eosinophils, neutrophils in epithelium, crypt destruction and erosion or ulcers). The Geboes score has 6 grades, each with 3-5 subgrades: Grade 0, structural change only; Grade 1, chronic inflammation; Grade 2, lamina propria neutrophils and eosinophils; Grade 3, neutrophils in epithelium; Grade 4, crypt destruction; and Grade 5, erosions or ulceration. A higher score is associated with higher disease activity.
Number of Participants With Mucosal Healing at Week 16Week 16Mucosal healing is defined as endoscopic remission (overall mucosal appearance at endoscopy subscore=0) and histological remission (Geboes score \<2.0 based on rectal biopsy). The endoscopic subscore ranges from 0 (normal or inactive disease) to 3 (severe disease with spontaneous bleeding, ulceration). The Geboes histologic index includes seven histological features (architectural change, chronic inflammatory infiltrate, lamina propria neutrophils and eosinophils, neutrophils in epithelium, crypt destruction and erosion or ulcers). The Geboes score has 6 grades, each with 3-5 subgrades: Grade 0, structural change only; Grade 1, chronic inflammation; Grade 2, lamina propria neutrophils and eosinophils; Grade 3, neutrophils in epithelium; Grade 4, crypt destruction; and Grade 5, erosions or ulceration. A higher score is associated with higher disease activity.
Number of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)Day 8, Day 29, Day 57, Day 85, Day 113, and Day 120 (End of Study)Participants recorded stool frequency using an electronic subject diary on a daily basis. The stool frequency subscore (SFS) ranges from 0 to 3 according to the following scale: Score 0: Normal number of stools Score 1: 1 to 2 stools per day more than normal Score 2: 3 to 4 stools per day more than normal Score 3: 5 or more stools per day more than normal Decreasing score indicates improvement.
Number of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineDay 8, Day 29, Day 57, Day 85, Day 113, and Day 120 (End of Study)Participants recorded rectal bleeding in an electronic subject diary on a daily basis. Rectal bleeding score (RBS) is taken as the worst subscore of the three most recent scores within 7 days prior to the visit. The rectal bleeding subscore ranges from 0 to 3 according to the following scale: Score 0: No blood seen Score 1: Streaks of blood with stool less than half the time Score 2: Obvious blood with stool most of the time Score 3: Blood alone passed A lower score represents an improvement in rectal bleeding.
Partial Modified Mayo Score Change From BaselineDay 8, Day 29, Day 57, Day 85, Day 113, and Day 120 (End of Study)Partial Modified Mayo Score (pMMS) Change from baseline The pMMS is a composite score of UC disease activity based on the following 2 subscores: 1. Stool frequency subscore (SFS), scored from 0 (normal number of stools per day) to 3 (5 or more stools per day more than normal). 2. Rectal bleeding subscore (RBS), scored from 0 (no blood seen) to 3 (blood alone passed). The overall pMMS score ranges from 0 to 6 with higher scores representing more severe disease.
Reduction From Baseline in MMS at Week 16Week 16Reduction from baseline in Modified Mayo Score (MMS) MMS is a composite score of UC disease activity based on the following 3 subscores: 1. Stool frequency subscore (SFS), scored from 0 (normal number of stools) to 3 (5 or more stools more than normal). 2. Rectal bleeding subscore (RBS), scored from 0 (no blood seen) to 3 (blood alone passed). 3. Endoscopic subscore, scored from 0 (normal or inactive disease) to 3 (severe disease, spontaneous bleeding, ulceration). The overall MMS ranges from 0 to 9 where higher scores represent more severe disease.
Number of Participants With Reduction Relative to Baseline in C Reactive Protein at Weeks 8 and 16Week 8 and Week 16CRP is an acute-phase protein which provides an objective criterion of inflammatory activity. CRP has a short half-life (19 hours) and therefore rises early after the onset of inflammation and rapidly decreases after resolution of the inflammation. It is induced by interleukin-6, TNF-alpha and other pro-inflammatory cytokines that are produced within the intestinal lamina propria. Outcome will be measured based on a reduction in CRP relative to baseline values.
miRNA-124 Expression (Copy Number) in Whole Blood at Week 8 and Week 16Week 8 and Week 16Absolute quantification (QuantaSoft Pro) of the miR-124 copy number was performed at Week 8 and Week 16 using droplet digital PCR technology (ddPCR) on whole blood samples. 0 in the placebo column means no signal, so BLQ (Below the level of quantification).
IL-6 Serum ConcentrationsDay 1Serum samples from participants who received ABX464 (25, 50 or 100 mg) or placebo were collected during 5 visits (Day 1, Day 8, Day 29, Day 57, and Day 113). IL6 was measured using the 8-plex assay on the ELLA Platform (Biotechne). All samples were tested in duplicate at the minimum required dilution. Baseline (Day 1) values are calculated as below: x1/arithmetic mean of baseline values x 100, where the arithmetic mean is defined by (x1 + x2+...+xn)/n (summing all baseline values and dividing by the total number of values n) The post baseline values are calculated as follow: post-baseline IL-6 values - Day 1 IL-6 values/Day 1 IL-6 values)\*100
Number of Participants With Endoscopic Remission at Week 8Week 8Endoscopic remission is defined as an endoscopic subscore of 0. Endoscopies were assessed by a blinded central reader and scored according to the following scale: 0 = Normal or inactive disease; 1. = Mild disease (erythema, decreased vascular pattern); 2. = Moderate disease (marked erythema, lack of vascular pattern, any friability, erosions); 3. = Severe disease (spontaneous bleeding, ulceration). A higher score represents more severe disease.
Number of Participants With Endoscopic Remission at Week 16Week 16Endoscopic remission is defined as an endoscopic subscore of 0. Endoscopies were assessed by a blinded central reader and scored according to the following scale: 0 = Normal or inactive disease; 1. = Mild disease (erythema, decreased vascular pattern); 2. = Moderate disease (marked erythema, lack of vascular pattern, any friability, erosions); 3. = Severe disease (spontaneous bleeding, ulceration). A higher score represents more severe disease.
IL-10 Serum ConcentrationsDay 1Serum samples from patients who received ABX464 (25, 50 or 100 mg) or placebo were collected during 5 visits (Day 1, Day 8, Day 29, Day 57, and Day 113). IL10 was measured using the 8-plex assay on the ELLA Platform. All samples were tested in duplicate at the minimum required dilution. Baseline (Day 1) values are calculated as below: x1/arithmetic mean of baseline values x 100, where the arithmetic mean is defined by (x1 + x2+...+xn)/n (summing all baseline values and dividing by the total number of values n) The post baseline values are calculated as follow: post-baseline IL-10 values - Day 1 IL-10 values/Day 1 IL-10 values)\*100
IL-1B Serum ConcentrationsDay 1Serum samples from patients who received ABX464 (25, 50, or 100 mg) or placebo were collected during 5 visits (Day 1, Day 8, Day 29, Day 57 and Day 113). IL1beta was measured using the 8-plex assay on the ELLA Platform. All samples were tested in duplicate at the minimum required dilution. Baseline (Day 1) values are calculated as below: x1/arithmetic mean of baseline values x 100, where the arithmetic mean is defined by (x1 + x2+...+xn)/n (summing all baseline values and dividing by the total number of values n) The post baseline values are calculated as follow: post-baseline IL-1B values - Day 1 IL-1B values/Day 1 IL-1B values)\*100
TNFα Serum ConcentrationsDay 1Serum samples from patients who received ABX464 (25, 50, or 100 mg) or placebo were collected during 5 visits (Day 1, Day 8, Day 29, Day 57 and Day 113 TNF-alpha was measured using the 8-plex assay on the ELLA Platform. All samples were tested in duplicate at the minimum required dilution. Baseline (Day 1) values are calculated as below: x1/arithmetic mean of baseline values x 100, where the arithmetic mean is defined by (x1 + x2+...+xn)/n (summing all baseline values and dividing by the total number of values n) The post baseline values are calculated as follow: post-baseline TNFα values - Day 1 TNFα values/Day 1 TNFα values)\*100
Change From Baseline in Infiltrate/Histopathology Using Robarts Histopathology Index (RHI) at Week 8 and Week 16Week 8 and Week 16Infiltrate/Histopathology (Rectal/Sigmoidal Biopsies) using the Robarts Histopathology Index (RHI) Week 8 and Week 16 biopsies will be compared to biopsies at baseline to assess the disease evolution at a tissue level, based on the Robarts Histological Index. The score ranges from 0 (no disease activity) to 33 (severe disease activity) is based on evaluation of 4 parameters: chronic inflammatory infiltrate, lamina propria neutrophils and eosinophils, neutrophils in the epithelium and erosion and ulceration. A higher score indicates more severe disease.
Change From Baseline in Infiltrate/Histopathology - Geboes Score at Week 8 and Week 16Week 8 and Week 16The Geboes score is composed of 6 major grades that assess different aspects of the biopsy findings, with each grade having its own score range: 1. Structural Changes (Grade 0): Range: 0 (No changes) to 3 (Severe changes) 2. Chronic Inflammation (Grade 1): Range: 0 (No inflammation) to 3 (Severe inflammation) 3. Lamina Propria Neutrophils (Grade 2): Range: 0 (None) to 3 (Severe infiltration of neutrophils) 4. Neutrophils in the Epithelium (Grade 3): Range: 0 (None) to 3 (Severe neutrophil infiltration) 5. Crypt Destruction (Grade 4): Range: 0 (No destruction) to 3 (Severe crypt destruction) 6. Erosion and Ulcers (Grade 5): Range: 0 (None) to 3 (Severe erosion/ulceration) Subscales are summed across all 6 grades, final total score between 0 and 18 : * 0-5: Minimal or no inflammation * 6-10: Mild inflammation * 11-15: Moderate inflammation * 16-18: Severe inflammation or damage A higher score indicates more severe disease
Number of Participants With Reduction Relative to Baseline in Fecal Calprotectin at Weeks 8 and 16Week 8 and Week 16Fecal Calprotectin (FC) is a non-invasive surrogate marker of inflammation in the small intestine and levels below 250 ug/g is associated with mucosal healing. FC levels were measured using enzyme-linked immunosorbent assay (ELISA) and/or a validated quantitative rapid test. Outcome will be measured based on a reduction in FC relative to baseline values.

Countries

Austria, Belarus, Belgium, Canada, Czechia, France, Germany, Hungary, Italy, Poland, Serbia, Slovakia, Slovenia, Spain, Ukraine, United Kingdom, United States

Participant flow

Recruitment details

A total of 355 patients consented to participate, 254 patients were randomized. A total of 253 patients were treated, 222 patients completed study treatment. 32 patients discontinued and 1 patient was randomized but did not receive study drug. One further patient was excluded from the Full Analysis Set (FAS) due to noncompliance with inclusion/exclusion criteria. A total of 252 patients were included in the FAS (64: ABX464 100mg q.d, 63: ABX464 50mg q.d, 61: ABX464 25mg q.d and 64: placebo).

Pre-assignment details

Randomization to treatment arms was stratified by previous exposure/non-exposure to biologics and JAK inhibitors treatment use and US/non-US sites.

Participants by arm

ArmCount
ABX464 100 mg
ABX464 100 mg: ABX464 100mg (two capsules of ABX464 50 mg) once daily for 16 weeks
64
ABX464 50 mg
ABX464 50 mg: ABX464 50mg (one capsule of ABX464 50 mg + one capsule of placebo) once daily for 16 weeks
63
ABX464 25mg
ABX464 25 mg: ABX464 25mg (one capsule of ABX464 25 mg + one capsule of placebo) once daily for 16 weeks
61
Matching Placebo
Matching placebo will be administered orally (capsules) once daily for 16 weeks Placebo: Two capsules of placebo once daily for 16 weeks
64
Total252

Baseline characteristics

CharacteristicABX464 100 mgABX464 50 mgABX464 25mgMatching PlaceboTotal
Age, Categorical
<=18 years
0 Participants0 Participants0 Participants0 Participants0 Participants
Age, Categorical
>=65 years
3 Participants3 Participants5 Participants4 Participants15 Participants
Age, Categorical
Between 18 and 65 years
61 Participants60 Participants56 Participants60 Participants237 Participants
Age, Continuous42.2 Years
STANDARD_DEVIATION 12.34
40.2 Years
STANDARD_DEVIATION 13.94
41.5 Years
STANDARD_DEVIATION 14.16
41.1 Years
STANDARD_DEVIATION 14.43
41.2 Years
STANDARD_DEVIATION 13.67
Baseline Modified Mayo Score (MMS)
Baseline MMS: 4
0 Participants0 Participants0 Participants1 Participants1 Participants
Baseline Modified Mayo Score (MMS)
Baseline MMS: 5 to 6
17 Participants16 Participants17 Participants21 Participants71 Participants
Baseline Modified Mayo Score (MMS)
Baseline MMS: 7 to 9
47 Participants47 Participants44 Participants42 Participants180 Participants
Race and Ethnicity Not Collected0 Participants
Region of Enrollment
Austria
1 participants1 participants1 participants3 participants6 participants
Region of Enrollment
Belgium
4 participants2 participants0 participants2 participants8 participants
Region of Enrollment
Canada
1 participants1 participants2 participants1 participants5 participants
Region of Enrollment
Czechia
2 participants6 participants4 participants2 participants14 participants
Region of Enrollment
France
8 participants8 participants7 participants7 participants30 participants
Region of Enrollment
Germany
5 participants3 participants4 participants4 participants16 participants
Region of Enrollment
Hungary
5 participants5 participants5 participants7 participants22 participants
Region of Enrollment
Italy
5 participants2 participants6 participants7 participants20 participants
Region of Enrollment
Poland
16 participants16 participants18 participants20 participants70 participants
Region of Enrollment
Serbia
0 participants3 participants2 participants0 participants5 participants
Region of Enrollment
Slovakia
3 participants7 participants5 participants3 participants18 participants
Region of Enrollment
Slovenia
1 participants1 participants1 participants0 participants3 participants
Region of Enrollment
Spain
1 participants0 participants0 participants0 participants1 participants
Region of Enrollment
Ukraine
12 participants7 participants6 participants7 participants32 participants
Region of Enrollment
United States
0 participants1 participants0 participants1 participants2 participants
Sex: Female, Male
Female
23 Participants36 Participants21 Participants24 Participants104 Participants
Sex: Female, Male
Male
41 Participants27 Participants40 Participants40 Participants148 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
deaths
Total, all-cause mortality
0 / 640 / 630 / 620 / 64
other
Total, other adverse events
45 / 6438 / 6333 / 6230 / 64
serious
Total, serious adverse events
4 / 644 / 631 / 624 / 64

Outcome results

Primary

Reduction From Baseline in Modified Mayo Score (MMS) at Week 8

Reduction from baseline in Modified Mayo Score (MMS) MMS is a composite score of UC disease activity based on the following 3 subscores: 1. Stool frequency subscore (SFS), scored from 0 (normal number of stools) to 3 (5 or more stools more than normal). 2. Rectal bleeding subscore (RBS), scored from 0 (no blood seen) to 3 (blood alone passed). 3. Endoscopic subscore, scored from 0 (normal or inactive disease) to 3 (severe disease, spontaneous bleeding, ulceration). The overall MMS ranges from 0 to 9 where higher scores represent more severe disease.

Time frame: Week 8

Population: Number of patients in the category with data available for baseline and the respective visit.

ArmMeasureValue (LEAST_SQUARES_MEAN)
ABX464 100 mgReduction From Baseline in Modified Mayo Score (MMS) at Week 8-2.9 Score
ABX464 50 mgReduction From Baseline in Modified Mayo Score (MMS) at Week 8-3.2 Score
ABX464 25 mgReduction From Baseline in Modified Mayo Score (MMS) at Week 8-3.1 Score
Matching PlaceboReduction From Baseline in Modified Mayo Score (MMS) at Week 8-1.9 Score
Secondary

Change From Baseline in Infiltrate/Histopathology - Geboes Score at Week 8 and Week 16

The Geboes score is composed of 6 major grades that assess different aspects of the biopsy findings, with each grade having its own score range: 1. Structural Changes (Grade 0): Range: 0 (No changes) to 3 (Severe changes) 2. Chronic Inflammation (Grade 1): Range: 0 (No inflammation) to 3 (Severe inflammation) 3. Lamina Propria Neutrophils (Grade 2): Range: 0 (None) to 3 (Severe infiltration of neutrophils) 4. Neutrophils in the Epithelium (Grade 3): Range: 0 (None) to 3 (Severe neutrophil infiltration) 5. Crypt Destruction (Grade 4): Range: 0 (No destruction) to 3 (Severe crypt destruction) 6. Erosion and Ulcers (Grade 5): Range: 0 (None) to 3 (Severe erosion/ulceration) Subscales are summed across all 6 grades, final total score between 0 and 18 : * 0-5: Minimal or no inflammation * 6-10: Mild inflammation * 11-15: Moderate inflammation * 16-18: Severe inflammation or damage A higher score indicates more severe disease

Time frame: Week 8 and Week 16

Population: Only samples which were collected have been analyzed and included baseline and data for week 8 or week 16. Patients that were evaluated with an endoscopy at week 16 are the subset of patients that did not achieve endoscopic improvement at week 8

ArmMeasureGroupValue (LEAST_SQUARES_MEAN)
ABX464 100 mgChange From Baseline in Infiltrate/Histopathology - Geboes Score at Week 8 and Week 16Week 8-4.8 Score change from baseline
ABX464 100 mgChange From Baseline in Infiltrate/Histopathology - Geboes Score at Week 8 and Week 16Week 16-4.4 Score change from baseline
ABX464 50 mgChange From Baseline in Infiltrate/Histopathology - Geboes Score at Week 8 and Week 16Week 16-3.9 Score change from baseline
ABX464 50 mgChange From Baseline in Infiltrate/Histopathology - Geboes Score at Week 8 and Week 16Week 8-3.3 Score change from baseline
ABX464 25 mgChange From Baseline in Infiltrate/Histopathology - Geboes Score at Week 8 and Week 16Week 8-4.1 Score change from baseline
ABX464 25 mgChange From Baseline in Infiltrate/Histopathology - Geboes Score at Week 8 and Week 16Week 16-4.7 Score change from baseline
Matching PlaceboChange From Baseline in Infiltrate/Histopathology - Geboes Score at Week 8 and Week 16Week 8-1.9 Score change from baseline
Matching PlaceboChange From Baseline in Infiltrate/Histopathology - Geboes Score at Week 8 and Week 16Week 16-1.3 Score change from baseline
Secondary

Change From Baseline in Infiltrate/Histopathology Using Robarts Histopathology Index (RHI) at Week 8 and Week 16

Infiltrate/Histopathology (Rectal/Sigmoidal Biopsies) using the Robarts Histopathology Index (RHI) Week 8 and Week 16 biopsies will be compared to biopsies at baseline to assess the disease evolution at a tissue level, based on the Robarts Histological Index. The score ranges from 0 (no disease activity) to 33 (severe disease activity) is based on evaluation of 4 parameters: chronic inflammatory infiltrate, lamina propria neutrophils and eosinophils, neutrophils in the epithelium and erosion and ulceration. A higher score indicates more severe disease.

Time frame: Week 8 and Week 16

Population: Only samples which were collected have been analyzed. Patients that were evaluated with an endoscopy at week 16 are the subset of patients that did not achieve endoscopic improvement at week 8

ArmMeasureGroupValue (LEAST_SQUARES_MEAN)
ABX464 100 mgChange From Baseline in Infiltrate/Histopathology Using Robarts Histopathology Index (RHI) at Week 8 and Week 16Week 8-7.3 score on a scale
ABX464 100 mgChange From Baseline in Infiltrate/Histopathology Using Robarts Histopathology Index (RHI) at Week 8 and Week 16Week 16-7.6 score on a scale
ABX464 50 mgChange From Baseline in Infiltrate/Histopathology Using Robarts Histopathology Index (RHI) at Week 8 and Week 16Week 16-5.8 score on a scale
ABX464 50 mgChange From Baseline in Infiltrate/Histopathology Using Robarts Histopathology Index (RHI) at Week 8 and Week 16Week 8-5.9 score on a scale
ABX464 25 mgChange From Baseline in Infiltrate/Histopathology Using Robarts Histopathology Index (RHI) at Week 8 and Week 16Week 8-7.3 score on a scale
ABX464 25 mgChange From Baseline in Infiltrate/Histopathology Using Robarts Histopathology Index (RHI) at Week 8 and Week 16Week 16-8.0 score on a scale
Matching PlaceboChange From Baseline in Infiltrate/Histopathology Using Robarts Histopathology Index (RHI) at Week 8 and Week 16Week 8-3.4 score on a scale
Matching PlaceboChange From Baseline in Infiltrate/Histopathology Using Robarts Histopathology Index (RHI) at Week 8 and Week 16Week 16-2.8 score on a scale
Secondary

IL-10 Serum Concentrations

Serum samples from patients who received ABX464 (25, 50 or 100 mg) or placebo were collected during 5 visits (Day 1, Day 8, Day 29, Day 57, and Day 113). IL10 was measured using the 8-plex assay on the ELLA Platform. All samples were tested in duplicate at the minimum required dilution. Baseline (Day 1) values are calculated as below: x1/arithmetic mean of baseline values x 100, where the arithmetic mean is defined by (x1 + x2+...+xn)/n (summing all baseline values and dividing by the total number of values n) The post baseline values are calculated as follow: post-baseline IL-10 values - Day 1 IL-10 values/Day 1 IL-10 values)\*100

Time frame: Day 8, Day 29, Week 8 and Week 16

Population: Only samples which were collected have been analyzed

ArmMeasureGroupValue (MEAN)Dispersion
ABX464 100 mgIL-10 Serum ConcentrationsDay 8100.3 Percent ChangeStandard Error 4.596
ABX464 100 mgIL-10 Serum ConcentrationsDay 2998.71 Percent ChangeStandard Error 6.626
ABX464 100 mgIL-10 Serum ConcentrationsWeek 8 (Day 57)96.00 Percent ChangeStandard Error 5.59
ABX464 100 mgIL-10 Serum ConcentrationsWeek 16 (Day 113)103.9 Percent ChangeStandard Error 7.435
ABX464 50 mgIL-10 Serum ConcentrationsWeek 16 (Day 113)92.50 Percent ChangeStandard Error 4.879
ABX464 50 mgIL-10 Serum ConcentrationsDay 8102.3 Percent ChangeStandard Error 5.827
ABX464 50 mgIL-10 Serum ConcentrationsWeek 8 (Day 57)99.30 Percent ChangeStandard Error 7.431
ABX464 50 mgIL-10 Serum ConcentrationsDay 2987.22 Percent ChangeStandard Error 3.638
ABX464 25 mgIL-10 Serum ConcentrationsWeek 8 (Day 57)89.30 Percent ChangeStandard Error 4.289
ABX464 25 mgIL-10 Serum ConcentrationsDay 8101 Percent ChangeStandard Error 4.288
ABX464 25 mgIL-10 Serum ConcentrationsWeek 16 (Day 113)91.24 Percent ChangeStandard Error 4.911
ABX464 25 mgIL-10 Serum ConcentrationsDay 2991.40 Percent ChangeStandard Error 4.519
Matching PlaceboIL-10 Serum ConcentrationsDay 8100.1 Percent ChangeStandard Error 3.918
Matching PlaceboIL-10 Serum ConcentrationsDay 29102.5 Percent ChangeStandard Error 4.728
Matching PlaceboIL-10 Serum ConcentrationsWeek 8 (Day 57)94.18 Percent ChangeStandard Error 4.886
Matching PlaceboIL-10 Serum ConcentrationsWeek 16 (Day 113)91.85 Percent ChangeStandard Error 5.943
Secondary

IL-10 Serum Concentrations

Serum samples from patients who received ABX464 (25, 50 or 100 mg) or placebo were collected during 5 visits (Day 1, Day 8, Day 29, Day 57, and Day 113). IL10 was measured using the 8-plex assay on the ELLA Platform. All samples were tested in duplicate at the minimum required dilution. Baseline (Day 1) values are calculated as below: x1/arithmetic mean of baseline values x 100, where the arithmetic mean is defined by (x1 + x2+...+xn)/n (summing all baseline values and dividing by the total number of values n) The post baseline values are calculated as follow: post-baseline IL-10 values - Day 1 IL-10 values/Day 1 IL-10 values)\*100

Time frame: Day 1

Population: Only samples which were collected have been analyzed

ArmMeasureValue (MEAN)Dispersion
ABX464 100 mgIL-10 Serum Concentrations100 Percentage of IL-10Standard Error 8.982
ABX464 50 mgIL-10 Serum Concentrations100 Percentage of IL-10Standard Error 6.989
ABX464 25 mgIL-10 Serum Concentrations100 Percentage of IL-10Standard Error 18.98
Matching PlaceboIL-10 Serum Concentrations100 Percentage of IL-10Standard Error 17.54
Secondary

IL-1B Serum Concentrations

Serum samples from patients who received ABX464 (25, 50, or 100 mg) or placebo were collected during 5 visits (Day 1, Day 8, Day 29, Day 57 and Day 113). IL1beta was measured using the 8-plex assay on the ELLA Platform. All samples were tested in duplicate at the minimum required dilution. Baseline (Day 1) values are calculated as below: x1/arithmetic mean of baseline values x 100, where the arithmetic mean is defined by (x1 + x2+...+xn)/n (summing all baseline values and dividing by the total number of values n) The post baseline values are calculated as follow: post-baseline IL-1B values - Day 1 IL-1B values/Day 1 IL-1B values)\*100

Time frame: Day 8, Day 29, Day 57 and Day 113

Population: Only samples which were collected have been analyzed

ArmMeasureGroupValue (MEAN)Dispersion
ABX464 100 mgIL-1B Serum ConcentrationsDay 8102.8 Percent ChangeStandard Error 7.453
ABX464 100 mgIL-1B Serum ConcentrationsDay 29115 Percent ChangeStandard Error 9.424
ABX464 100 mgIL-1B Serum ConcentrationsWeek 8 (Day 57)105.3 Percent ChangeStandard Error 5.735
ABX464 100 mgIL-1B Serum ConcentrationsWeek 16 (Day 113)102.4 Percent ChangeStandard Error 6.513
ABX464 50 mgIL-1B Serum ConcentrationsDay 29101.3 Percent ChangeStandard Error 5.435
ABX464 50 mgIL-1B Serum ConcentrationsWeek 8 (Day 57)100.3 Percent ChangeStandard Error 6.49
ABX464 50 mgIL-1B Serum ConcentrationsWeek 16 (Day 113)137.5 Percent ChangeStandard Error 26.11
ABX464 50 mgIL-1B Serum ConcentrationsDay 8118.2 Percent ChangeStandard Error 10.44
ABX464 25 mgIL-1B Serum ConcentrationsWeek 8 (Day 57)99 Percent ChangeStandard Error 6.605
ABX464 25 mgIL-1B Serum ConcentrationsDay 29138 Percent ChangeStandard Error 41.41
ABX464 25 mgIL-1B Serum ConcentrationsWeek 16 (Day 113)124.1 Percent ChangeStandard Error 12.24
ABX464 25 mgIL-1B Serum ConcentrationsDay 8103.7 Percent ChangeStandard Error 5.562
Matching PlaceboIL-1B Serum ConcentrationsWeek 16 (Day 113)109 Percent ChangeStandard Error 7.042
Matching PlaceboIL-1B Serum ConcentrationsDay 29112.6 Percent ChangeStandard Error 7.052
Matching PlaceboIL-1B Serum ConcentrationsDay 8111 Percent ChangeStandard Error 5.203
Matching PlaceboIL-1B Serum ConcentrationsWeek 8 (Day 57)124.1 Percent ChangeStandard Error 12.24
Secondary

IL-1B Serum Concentrations

Serum samples from patients who received ABX464 (25, 50, or 100 mg) or placebo were collected during 5 visits (Day 1, Day 8, Day 29, Day 57 and Day 113). IL1beta was measured using the 8-plex assay on the ELLA Platform. All samples were tested in duplicate at the minimum required dilution. Baseline (Day 1) values are calculated as below: x1/arithmetic mean of baseline values x 100, where the arithmetic mean is defined by (x1 + x2+...+xn)/n (summing all baseline values and dividing by the total number of values n) The post baseline values are calculated as follow: post-baseline IL-1B values - Day 1 IL-1B values/Day 1 IL-1B values)\*100

Time frame: Day 1

Population: Only samples which were collected have been analyzed

ArmMeasureValue (MEAN)Dispersion
ABX464 100 mgIL-1B Serum Concentrations100 Percentage of IL-1BStandard Error 6.514
ABX464 50 mgIL-1B Serum Concentrations100 Percentage of IL-1BStandard Error 8.988
ABX464 25 mgIL-1B Serum Concentrations100 Percentage of IL-1BStandard Error 7.043
Matching PlaceboIL-1B Serum Concentrations100 Percentage of IL-1BStandard Error 4.87
Secondary

IL-6 Serum Concentrations

Serum samples from participants who received ABX464 (25, 50 or 100 mg) or placebo were collected during 5 visits (Day 1, Day 8, Day 29, Day 57, and Day 113). IL6 was measured using the 8-plex assay on the ELLA Platform (Biotechne). All samples were tested in duplicate at the minimum required dilution. Baseline (Day 1) values are calculated as below: x1/arithmetic mean of baseline values x 100, where the arithmetic mean is defined by (x1 + x2+...+xn)/n (summing all baseline values and dividing by the total number of values n) The post baseline values are calculated as follow: post-baseline IL-6 values - Day 1 IL-6 values/Day 1 IL-6 values)\*100

Time frame: Day 1

Population: Only samples which were collected have been analyzed

ArmMeasureValue (MEAN)Dispersion
ABX464 100 mgIL-6 Serum Concentrations100 Percentage of IL-6Standard Error 10.77
ABX464 50 mgIL-6 Serum Concentrations100 Percentage of IL-6Standard Error 13.36
ABX464 25 mgIL-6 Serum Concentrations100 Percentage of IL-6Standard Error 19.37
Matching PlaceboIL-6 Serum Concentrations100 Percentage of IL-6Standard Error 28.77
Secondary

IL-6 Serum Concentrations

Serum samples from participants who received ABX464 (25, 50 or 100 mg) or placebo were collected during 5 visits (Day 1, Day 8, Day 29, Day 57, and Day 113). IL6 was measured using the 8-plex assay on the ELLA Platform (Biotechne). All samples were tested in duplicate at the minimum required dilution. Baseline (Day 1) values are calculated as below: x1/arithmetic mean of baseline values x 100, where the arithmetic mean is defined by (x1 + x2+...+xn)/n (summing all baseline values and dividing by the total number of values n) The post baseline values are calculated as follow: post-baseline IL-6 values - Day 1 IL-6 values/Day 1 IL-6 values)\*100

Time frame: Day 8, Day 29, Day 57, and Day 113

Population: Only samples which were collected have been analyzed

ArmMeasureGroupValue (MEAN)Dispersion
ABX464 100 mgIL-6 Serum ConcentrationsDay 8166.4 Percent ChangeStandard Error 20.98
ABX464 100 mgIL-6 Serum ConcentrationsDay 29117 Percent ChangeStandard Error 10.92
ABX464 100 mgIL-6 Serum ConcentrationsWeek 8 (Day 57)118.9 Percent ChangeStandard Error 11.3
ABX464 100 mgIL-6 Serum ConcentrationsWeek 16 (Day 113)108.3 Percent ChangeStandard Error 14.23
ABX464 50 mgIL-6 Serum ConcentrationsDay 2993.36 Percent ChangeStandard Error 12.19
ABX464 50 mgIL-6 Serum ConcentrationsWeek 8 (Day 57)150.6 Percent ChangeStandard Error 47.06
ABX464 50 mgIL-6 Serum ConcentrationsWeek 16 (Day 113)170.1 Percent ChangeStandard Error 56.4
ABX464 50 mgIL-6 Serum ConcentrationsDay 896.45 Percent ChangeStandard Error 9.034
ABX464 25 mgIL-6 Serum ConcentrationsWeek 8 (Day 57)89.75 Percent ChangeStandard Error 8.662
ABX464 25 mgIL-6 Serum ConcentrationsDay 2989.31 Percent ChangeStandard Error 8.608
ABX464 25 mgIL-6 Serum ConcentrationsWeek 16 (Day 113)98.29 Percent ChangeStandard Error 12.03
ABX464 25 mgIL-6 Serum ConcentrationsDay 8103.6 Percent ChangeStandard Error 8.641
Matching PlaceboIL-6 Serum ConcentrationsWeek 16 (Day 113)131.8 Percent ChangeStandard Error 16.97
Matching PlaceboIL-6 Serum ConcentrationsDay 29128.2 Percent ChangeStandard Error 10.85
Matching PlaceboIL-6 Serum ConcentrationsDay 8132.7 Percent ChangeStandard Error 15.18
Matching PlaceboIL-6 Serum ConcentrationsWeek 8 (Day 57)125.7 Percent ChangeStandard Error 17.11
Secondary

miRNA-124 Expression (Copy Number) in Whole Blood at Week 8 and Week 16

Absolute quantification (QuantaSoft Pro) of the miR-124 copy number was performed at Week 8 and Week 16 using droplet digital PCR technology (ddPCR) on whole blood samples. 0 in the placebo column means no signal, so BLQ (Below the level of quantification).

Time frame: Week 8 and Week 16

Population: Only samples which were collected have been analyzed

ArmMeasureGroupValue (MEAN)Dispersion
ABX464 100 mgmiRNA-124 Expression (Copy Number) in Whole Blood at Week 8 and Week 16Week 813753 copies number/cellStandard Deviation 12142
ABX464 100 mgmiRNA-124 Expression (Copy Number) in Whole Blood at Week 8 and Week 16Week 1613268 copies number/cellStandard Deviation 11134
ABX464 50 mgmiRNA-124 Expression (Copy Number) in Whole Blood at Week 8 and Week 16Week 167723 copies number/cellStandard Deviation 7477
ABX464 50 mgmiRNA-124 Expression (Copy Number) in Whole Blood at Week 8 and Week 16Week 88517 copies number/cellStandard Deviation 6252
ABX464 25 mgmiRNA-124 Expression (Copy Number) in Whole Blood at Week 8 and Week 16Week 164154 copies number/cellStandard Deviation 5273
ABX464 25 mgmiRNA-124 Expression (Copy Number) in Whole Blood at Week 8 and Week 16Week 84598 copies number/cellStandard Deviation 11348
Matching PlacebomiRNA-124 Expression (Copy Number) in Whole Blood at Week 8 and Week 16Week 1623.79 copies number/cellStandard Deviation 94.69
Matching PlacebomiRNA-124 Expression (Copy Number) in Whole Blood at Week 8 and Week 16Week 828.93 copies number/cellStandard Deviation 146.4
Secondary

Number of Participants in Clinical Remission Per MMS at Week 16

Number of participants who achieved clinical remission per Modified Mayo Score at Week 16 MMS is a composite score of UC disease activity based on the following 3 subscores: 1. Stool frequency subscore (SFS), scored from 0 (normal number of stools) to 3 (5 or more stools more than normal). 2. Rectal bleeding subscore (RBS), scored from 0 (no blood seen) to 3 (blood alone passed). 3. Endoscopic subscore, scored from 0 (normal or inactive disease) to 3 (severe disease, spontaneous bleeding, ulceration). The overall MMS ranges from 0 to 9 where higher scores represent more severe disease. Clinical remission is defined as SFS ≤ 1, RBS of 0, and endoscopic subscore ≤ 1 (modified to exclude friability)

Time frame: Week 16

Population: Number of patients in the category with data available for baseline and the respective visit.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
ABX464 100 mgNumber of Participants in Clinical Remission Per MMS at Week 167 Participants
ABX464 50 mgNumber of Participants in Clinical Remission Per MMS at Week 166 Participants
ABX464 25 mgNumber of Participants in Clinical Remission Per MMS at Week 169 Participants
Matching PlaceboNumber of Participants in Clinical Remission Per MMS at Week 166 Participants
Secondary

Number of Participants in Clinical Remission Per MMS at Week 8

Number of participants who achieved clinical remission per Modified Mayo Score at Week 8 MMS is a composite score of UC disease activity based on the following 3 subscores: 1. Stool frequency subscore (SFS), scored from 0 (normal number of stools) to 3 (5 or more stools more than normal). 2. Rectal bleeding subscore (RBS), scored from 0 (no blood seen) to 3 (blood alone passed). 3. Endoscopic subscore, scored from 0 (normal or inactive disease) to 3 (severe disease, spontaneous bleeding, ulceration). The overall MMS ranges from 0 to 9 where higher scores represent more severe disease. Clinical remission is defined as SFS ≤ 1, RBS of 0, and endoscopic subscore ≤ 1 (modified to exclude friability)

Time frame: Week 8

Population: Full analysis set

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
ABX464 100 mgNumber of Participants in Clinical Remission Per MMS at Week 816 Participants
ABX464 50 mgNumber of Participants in Clinical Remission Per MMS at Week 811 Participants
ABX464 25 mgNumber of Participants in Clinical Remission Per MMS at Week 816 Participants
Matching PlaceboNumber of Participants in Clinical Remission Per MMS at Week 88 Participants
Secondary

Number of Participants With Clinical Response at Week 16

Clinical response is defined as a reduction in MMS of at least 2 points and greater than or equal to 30 percent from baseline with an accompanying decrease in rectal bleeding sub-score of greater than or equal to 1 point or absolute rectal bleeding sub-score of less than or equal to 1 point.

Time frame: Week 16

Population: Number of patients in the category with data available for baseline and the respective visit.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
ABX464 100 mgNumber of Participants With Clinical Response at Week 1619 Participants
ABX464 50 mgNumber of Participants With Clinical Response at Week 1620 Participants
ABX464 25 mgNumber of Participants With Clinical Response at Week 1625 Participants
Matching PlaceboNumber of Participants With Clinical Response at Week 1620 Participants
Secondary

Number of Participants With Clinical Response at Week 8

Clinical response is defined as a reduction in MMS of at least 2 points and greater than or equal to 30 percent from baseline with an accompanying decrease in rectal bleeding sub-score of greater than or equal to 1 point or absolute rectal bleeding sub-score of less than or equal to 1 point.

Time frame: Week 8

Population: Full analysis set

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
ABX464 100 mgNumber of Participants With Clinical Response at Week 832 Participants
ABX464 50 mgNumber of Participants With Clinical Response at Week 837 Participants
ABX464 25 mgNumber of Participants With Clinical Response at Week 838 Participants
Matching PlaceboNumber of Participants With Clinical Response at Week 822 Participants
Secondary

Number of Participants With Endoscopic Improvement at Week 16

Endoscopic improvement is defined as an endoscopic subscore of 0 or 1 (excluding friability) Endoscopies were assessed by a blinded central reader and scored according to the following scale: 0 = Normal or inactive disease; 1. = Mild disease (erythema, decreased vascular pattern); 2. = Moderate disease (marked erythema, lack of vascular pattern, any friability, erosions); 3. = Severe disease (spontaneous bleeding, ulceration). A higher endoscopic score indicates more severe disease.

Time frame: Week 16

Population: Number of patients in the category with data available for baseline and the respective visit.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
ABX464 100 mgNumber of Participants With Endoscopic Improvement at Week 1611 Participants
ABX464 50 mgNumber of Participants With Endoscopic Improvement at Week 1612 Participants
ABX464 25 mgNumber of Participants With Endoscopic Improvement at Week 1611 Participants
Matching PlaceboNumber of Participants With Endoscopic Improvement at Week 169 Participants
Secondary

Number of Participants With Endoscopic Improvement at Week 8

Endoscopic improvement is defined as an endoscopic subscore of 0 or 1 (excluding friability) Endoscopies were assessed by a blinded central reader and scored according to the following scale: 0 = Normal or inactive disease; 1. = Mild disease (erythema, decreased vascular pattern); 2. = Moderate disease (marked erythema, lack of vascular pattern, any friability, erosions); 3. = Severe disease (spontaneous bleeding, ulceration). A higher endoscopic score indicates more severe disease.

Time frame: Week 8

Population: Number of patients in the category with data available for baseline and the respective visit.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
ABX464 100 mgNumber of Participants With Endoscopic Improvement at Week 824 Participants
ABX464 50 mgNumber of Participants With Endoscopic Improvement at Week 821 Participants
ABX464 25 mgNumber of Participants With Endoscopic Improvement at Week 820 Participants
Matching PlaceboNumber of Participants With Endoscopic Improvement at Week 88 Participants
Secondary

Number of Participants With Endoscopic Remission at Week 16

Endoscopic remission is defined as an endoscopic subscore of 0. Endoscopies were assessed by a blinded central reader and scored according to the following scale: 0 = Normal or inactive disease; 1. = Mild disease (erythema, decreased vascular pattern); 2. = Moderate disease (marked erythema, lack of vascular pattern, any friability, erosions); 3. = Severe disease (spontaneous bleeding, ulceration). A higher score represents more severe disease.

Time frame: Week 16

Population: Number of patients in the category with data available for baseline and the respective visit.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
ABX464 100 mgNumber of Participants With Endoscopic Remission at Week 161 Participants
ABX464 50 mgNumber of Participants With Endoscopic Remission at Week 161 Participants
ABX464 25 mgNumber of Participants With Endoscopic Remission at Week 162 Participants
Matching PlaceboNumber of Participants With Endoscopic Remission at Week 163 Participants
Secondary

Number of Participants With Endoscopic Remission at Week 8

Endoscopic remission is defined as an endoscopic subscore of 0. Endoscopies were assessed by a blinded central reader and scored according to the following scale: 0 = Normal or inactive disease; 1. = Mild disease (erythema, decreased vascular pattern); 2. = Moderate disease (marked erythema, lack of vascular pattern, any friability, erosions); 3. = Severe disease (spontaneous bleeding, ulceration). A higher score represents more severe disease.

Time frame: Week 8

Population: Number of participants with data for endoscopy relative to the number of patients in the relevant analysis set

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
ABX464 100 mgNumber of Participants With Endoscopic Remission at Week 82 Participants
ABX464 50 mgNumber of Participants With Endoscopic Remission at Week 85 Participants
ABX464 25 mgNumber of Participants With Endoscopic Remission at Week 84 Participants
Matching PlaceboNumber of Participants With Endoscopic Remission at Week 85 Participants
Secondary

Number of Participants With Mucosal Healing at Week 16

Mucosal healing is defined as endoscopic remission (overall mucosal appearance at endoscopy subscore=0) and histological remission (Geboes score \<2.0 based on rectal biopsy). The endoscopic subscore ranges from 0 (normal or inactive disease) to 3 (severe disease with spontaneous bleeding, ulceration). The Geboes histologic index includes seven histological features (architectural change, chronic inflammatory infiltrate, lamina propria neutrophils and eosinophils, neutrophils in epithelium, crypt destruction and erosion or ulcers). The Geboes score has 6 grades, each with 3-5 subgrades: Grade 0, structural change only; Grade 1, chronic inflammation; Grade 2, lamina propria neutrophils and eosinophils; Grade 3, neutrophils in epithelium; Grade 4, crypt destruction; and Grade 5, erosions or ulceration. A higher score is associated with higher disease activity.

Time frame: Week 16

Population: Full analysis set.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
ABX464 100 mgNumber of Participants With Mucosal Healing at Week 161 Participants
ABX464 50 mgNumber of Participants With Mucosal Healing at Week 160 Participants
ABX464 25 mgNumber of Participants With Mucosal Healing at Week 160 Participants
Matching PlaceboNumber of Participants With Mucosal Healing at Week 160 Participants
Secondary

Number of Participants With Mucosal Healing at Week 8

Mucosal healing is defined as endoscopic remission (overall mucosal appearance at endoscopy subscore=0) and histological remission (Geboes score \<2.0 based on rectal biopsy). The endoscopic subscore ranges from 0 (normal or inactive disease) to 3 (severe disease with spontaneous bleeding, ulceration). The Geboes histologic index includes seven histological features (architectural change, chronic inflammatory infiltrate, lamina propria neutrophils and eosinophils, neutrophils in epithelium, crypt destruction and erosion or ulcers). The Geboes score has 6 grades, each with 3-5 subgrades: Grade 0, structural change only; Grade 1, chronic inflammation; Grade 2, lamina propria neutrophils and eosinophils; Grade 3, neutrophils in epithelium; Grade 4, crypt destruction; and Grade 5, erosions or ulceration. A higher score is associated with higher disease activity.

Time frame: Week 8

Population: Full analysis set

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
ABX464 100 mgNumber of Participants With Mucosal Healing at Week 80 Participants
ABX464 50 mgNumber of Participants With Mucosal Healing at Week 81 Participants
ABX464 25 mgNumber of Participants With Mucosal Healing at Week 80 Participants
Matching PlaceboNumber of Participants With Mucosal Healing at Week 82 Participants
Secondary

Number of Participants With Reduction of Rectal Bleeding Frequency Relative to Baseline

Participants recorded rectal bleeding in an electronic subject diary on a daily basis. Rectal bleeding score (RBS) is taken as the worst subscore of the three most recent scores within 7 days prior to the visit. The rectal bleeding subscore ranges from 0 to 3 according to the following scale: Score 0: No blood seen Score 1: Streaks of blood with stool less than half the time Score 2: Obvious blood with stool most of the time Score 3: Blood alone passed A lower score represents an improvement in rectal bleeding.

Time frame: Day 8, Day 29, Day 57, Day 85, Day 113, and Day 120 (End of Study)

Population: Number of participants in the relevant analysis set and treatment group with data available.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
ABX464 100 mgNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineDay 825 Participants
ABX464 100 mgNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineDay 2944 Participants
ABX464 100 mgNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineWeek 8 (Day 57)48 Participants
ABX464 100 mgNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineDay 8547 Participants
ABX464 100 mgNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineWeek 16 (Day 113)50 Participants
ABX464 100 mgNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineEnd of study (Day 120)3 Participants
ABX464 50 mgNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineEnd of study (Day 120)4 Participants
ABX464 50 mgNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineDay 8539 Participants
ABX464 50 mgNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineDay 823 Participants
ABX464 50 mgNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineWeek 8 (Day 57)44 Participants
ABX464 50 mgNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineDay 2938 Participants
ABX464 50 mgNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineWeek 16 (Day 113)45 Participants
ABX464 25 mgNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineDay 2939 Participants
ABX464 25 mgNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineWeek 8 (Day 57)46 Participants
ABX464 25 mgNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineDay 8544 Participants
ABX464 25 mgNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineEnd of study (Day 120)1 Participants
ABX464 25 mgNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineWeek 16 (Day 113)46 Participants
ABX464 25 mgNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineDay 824 Participants
Matching PlaceboNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineWeek 16 (Day 113)37 Participants
Matching PlaceboNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineEnd of study (Day 120)1 Participants
Matching PlaceboNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineDay 2924 Participants
Matching PlaceboNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineDay 8535 Participants
Matching PlaceboNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineDay 816 Participants
Matching PlaceboNumber of Participants With Reduction of Rectal Bleeding Frequency Relative to BaselineWeek 8 (Day 57)33 Participants
Secondary

Number of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)

Participants recorded stool frequency using an electronic subject diary on a daily basis. The stool frequency subscore (SFS) ranges from 0 to 3 according to the following scale: Score 0: Normal number of stools Score 1: 1 to 2 stools per day more than normal Score 2: 3 to 4 stools per day more than normal Score 3: 5 or more stools per day more than normal Decreasing score indicates improvement.

Time frame: Day 8, Day 29, Day 57, Day 85, Day 113, and Day 120 (End of Study)

Population: Patients in the category relative to the number of patients in the relevant analysis set and treatment group with data available

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
ABX464 100 mgNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)Day 818 Participants
ABX464 100 mgNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)Day 2934 Participants
ABX464 100 mgNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)Week 8 (Day 57)39 Participants
ABX464 100 mgNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)Day 8541 Participants
ABX464 100 mgNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)Week 16 (Day 113)44 Participants
ABX464 100 mgNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)End of study (Day 120)3 Participants
ABX464 50 mgNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)End of study (Day 120)4 Participants
ABX464 50 mgNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)Day 8539 Participants
ABX464 50 mgNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)Day 822 Participants
ABX464 50 mgNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)Week 8 (Day 57)37 Participants
ABX464 50 mgNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)Day 2936 Participants
ABX464 50 mgNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)Week 16 (Day 113)39 Participants
ABX464 25 mgNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)Day 2935 Participants
ABX464 25 mgNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)Week 8 (Day 57)39 Participants
ABX464 25 mgNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)Day 8537 Participants
ABX464 25 mgNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)End of study (Day 120)1 Participants
ABX464 25 mgNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)Week 16 (Day 113)42 Participants
ABX464 25 mgNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)Day 814 Participants
Matching PlaceboNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)Week 16 (Day 113)38 Participants
Matching PlaceboNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)End of study (Day 120)1 Participants
Matching PlaceboNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)Day 2926 Participants
Matching PlaceboNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)Day 8530 Participants
Matching PlaceboNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)Day 812 Participants
Matching PlaceboNumber of Participants With Reduction of Stool Frequency Relative to Baseline (Day 1)Week 8 (Day 57)37 Participants
Secondary

Number of Participants With Reduction Relative to Baseline in C Reactive Protein at Weeks 8 and 16

CRP is an acute-phase protein which provides an objective criterion of inflammatory activity. CRP has a short half-life (19 hours) and therefore rises early after the onset of inflammation and rapidly decreases after resolution of the inflammation. It is induced by interleukin-6, TNF-alpha and other pro-inflammatory cytokines that are produced within the intestinal lamina propria. Outcome will be measured based on a reduction in CRP relative to baseline values.

Time frame: Week 8 and Week 16

Population: Number of patients in the relevant analysis set and treatment group, with non-missing values of the parameter

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
ABX464 100 mgNumber of Participants With Reduction Relative to Baseline in C Reactive Protein at Weeks 8 and 16Week 8 (Day 57)31 Participants
ABX464 100 mgNumber of Participants With Reduction Relative to Baseline in C Reactive Protein at Weeks 8 and 16Week 16 (Day 113)31 Participants
ABX464 50 mgNumber of Participants With Reduction Relative to Baseline in C Reactive Protein at Weeks 8 and 16Week 16 (Day 113)29 Participants
ABX464 50 mgNumber of Participants With Reduction Relative to Baseline in C Reactive Protein at Weeks 8 and 16Week 8 (Day 57)28 Participants
ABX464 25 mgNumber of Participants With Reduction Relative to Baseline in C Reactive Protein at Weeks 8 and 16Week 8 (Day 57)39 Participants
ABX464 25 mgNumber of Participants With Reduction Relative to Baseline in C Reactive Protein at Weeks 8 and 16Week 16 (Day 113)37 Participants
Matching PlaceboNumber of Participants With Reduction Relative to Baseline in C Reactive Protein at Weeks 8 and 16Week 8 (Day 57)29 Participants
Matching PlaceboNumber of Participants With Reduction Relative to Baseline in C Reactive Protein at Weeks 8 and 16Week 16 (Day 113)29 Participants
Secondary

Number of Participants With Reduction Relative to Baseline in Fecal Calprotectin at Weeks 8 and 16

Fecal Calprotectin (FC) is a non-invasive surrogate marker of inflammation in the small intestine and levels below 250 ug/g is associated with mucosal healing. FC levels were measured using enzyme-linked immunosorbent assay (ELISA) and/or a validated quantitative rapid test. Outcome will be measured based on a reduction in FC relative to baseline values.

Time frame: Week 8 and Week 16

Population: Number of patients in the relevant analysis set and treatment group, with non-missing values of the parameter

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
ABX464 100 mgNumber of Participants With Reduction Relative to Baseline in Fecal Calprotectin at Weeks 8 and 16Week 833 Participants
ABX464 100 mgNumber of Participants With Reduction Relative to Baseline in Fecal Calprotectin at Weeks 8 and 16Week 1637 Participants
ABX464 50 mgNumber of Participants With Reduction Relative to Baseline in Fecal Calprotectin at Weeks 8 and 16Week 1635 Participants
ABX464 50 mgNumber of Participants With Reduction Relative to Baseline in Fecal Calprotectin at Weeks 8 and 16Week 835 Participants
ABX464 25 mgNumber of Participants With Reduction Relative to Baseline in Fecal Calprotectin at Weeks 8 and 16Week 833 Participants
ABX464 25 mgNumber of Participants With Reduction Relative to Baseline in Fecal Calprotectin at Weeks 8 and 16Week 1637 Participants
Matching PlaceboNumber of Participants With Reduction Relative to Baseline in Fecal Calprotectin at Weeks 8 and 16Week 826 Participants
Matching PlaceboNumber of Participants With Reduction Relative to Baseline in Fecal Calprotectin at Weeks 8 and 16Week 1622 Participants
Secondary

Partial Modified Mayo Score Change From Baseline

Partial Modified Mayo Score (pMMS) Change from baseline The pMMS is a composite score of UC disease activity based on the following 2 subscores: 1. Stool frequency subscore (SFS), scored from 0 (normal number of stools per day) to 3 (5 or more stools per day more than normal). 2. Rectal bleeding subscore (RBS), scored from 0 (no blood seen) to 3 (blood alone passed). The overall pMMS score ranges from 0 to 6 with higher scores representing more severe disease.

Time frame: Day 8, Day 29, Day 57, Day 85, Day 113, and Day 120 (End of Study)

Population: Reduction in least squares mean pMMS for all treatment groups at each visit

ArmMeasureGroupValue (LEAST_SQUARES_MEAN)
ABX464 100 mgPartial Modified Mayo Score Change From BaselineDay 8-0.7 Score
ABX464 100 mgPartial Modified Mayo Score Change From BaselineDay 29-1.8 Score
ABX464 100 mgPartial Modified Mayo Score Change From BaselineWeek 8 (Day 57)-2.2 Score
ABX464 100 mgPartial Modified Mayo Score Change From BaselineDay 85-2.4 Score
ABX464 100 mgPartial Modified Mayo Score Change From BaselineWeek 16 (Day 113)-2.8 Score
ABX464 100 mgPartial Modified Mayo Score Change From BaselineEnd of Study (Day 120)-1.1 Score
ABX464 50 mgPartial Modified Mayo Score Change From BaselineEnd of Study (Day 120)-1.9 Score
ABX464 50 mgPartial Modified Mayo Score Change From BaselineDay 85-2.3 Score
ABX464 50 mgPartial Modified Mayo Score Change From BaselineDay 8-0.8 Score
ABX464 50 mgPartial Modified Mayo Score Change From BaselineWeek 8 (Day 57)-2.2 Score
ABX464 50 mgPartial Modified Mayo Score Change From BaselineDay 29-1.8 Score
ABX464 50 mgPartial Modified Mayo Score Change From BaselineWeek 16 (Day 113)-2.4 Score
ABX464 25 mgPartial Modified Mayo Score Change From BaselineDay 29-1.8 Score
ABX464 25 mgPartial Modified Mayo Score Change From BaselineWeek 8 (Day 57)-2.3 Score
ABX464 25 mgPartial Modified Mayo Score Change From BaselineDay 85-2.3 Score
ABX464 25 mgPartial Modified Mayo Score Change From BaselineEnd of Study (Day 120)-3.3 Score
ABX464 25 mgPartial Modified Mayo Score Change From BaselineWeek 16 (Day 113)-2.6 Score
ABX464 25 mgPartial Modified Mayo Score Change From BaselineDay 8-0.7 Score
Matching PlaceboPartial Modified Mayo Score Change From BaselineWeek 16 (Day 113)-2.0 Score
Matching PlaceboPartial Modified Mayo Score Change From BaselineEnd of Study (Day 120)-1.2 Score
Matching PlaceboPartial Modified Mayo Score Change From BaselineDay 29-0.9 Score
Matching PlaceboPartial Modified Mayo Score Change From BaselineDay 85-1.6 Score
Matching PlaceboPartial Modified Mayo Score Change From BaselineDay 8-0.4 Score
Matching PlaceboPartial Modified Mayo Score Change From BaselineWeek 8 (Day 57)-1.6 Score
Secondary

Reduction From Baseline in MMS at Week 16

Reduction from baseline in Modified Mayo Score (MMS) MMS is a composite score of UC disease activity based on the following 3 subscores: 1. Stool frequency subscore (SFS), scored from 0 (normal number of stools) to 3 (5 or more stools more than normal). 2. Rectal bleeding subscore (RBS), scored from 0 (no blood seen) to 3 (blood alone passed). 3. Endoscopic subscore, scored from 0 (normal or inactive disease) to 3 (severe disease, spontaneous bleeding, ulceration). The overall MMS ranges from 0 to 9 where higher scores represent more severe disease.

Time frame: Week 16

Population: Number of patients in the category with data available for baseline and the respective visit.

ArmMeasureGroupValue (LEAST_SQUARES_MEAN)
ABX464 100 mgReduction From Baseline in MMS at Week 16Overall-3.6 Score
ABX464 100 mgReduction From Baseline in MMS at Week 16Without Previous Biologics or JAK Inhibitors Exposure-3.6 Score
ABX464 100 mgReduction From Baseline in MMS at Week 16With Previous Biologics or JAK Inhibitors Exposure-3.3 Score
ABX464 50 mgReduction From Baseline in MMS at Week 16Overall-3.2 Score
ABX464 50 mgReduction From Baseline in MMS at Week 16Without Previous Biologics or JAK Inhibitors Exposure-3.4 Score
ABX464 50 mgReduction From Baseline in MMS at Week 16With Previous Biologics or JAK Inhibitors Exposure-3.0 Score
ABX464 25 mgReduction From Baseline in MMS at Week 16With Previous Biologics or JAK Inhibitors Exposure-2.9 Score
ABX464 25 mgReduction From Baseline in MMS at Week 16Overall-3.3 Score
ABX464 25 mgReduction From Baseline in MMS at Week 16Without Previous Biologics or JAK Inhibitors Exposure-3.7 Score
Matching PlaceboReduction From Baseline in MMS at Week 16Overall-2.4 Score
Matching PlaceboReduction From Baseline in MMS at Week 16Without Previous Biologics or JAK Inhibitors Exposure-3.4 Score
Matching PlaceboReduction From Baseline in MMS at Week 16With Previous Biologics or JAK Inhibitors Exposure-1.3 Score
Secondary

TNFα Serum Concentrations

Serum samples from patients who received ABX464 (25, 50, or 100 mg) or placebo were collected during 5 visits (Day 1, Day 8, Day 29, Day 57 and Day 113 TNF-alpha was measured using the 8-plex assay on the ELLA Platform. All samples were tested in duplicate at the minimum required dilution. Baseline (Day 1) values are calculated as below: x1/arithmetic mean of baseline values x 100, where the arithmetic mean is defined by (x1 + x2+...+xn)/n (summing all baseline values and dividing by the total number of values n) The post baseline values are calculated as follow: post-baseline TNFα values - Day 1 TNFα values/Day 1 TNFα values)\*100

Time frame: Day 1

Population: Only samples which were collected have been analyzed

ArmMeasureValue (MEAN)Dispersion
ABX464 100 mgTNFα Serum Concentrations100 Percentage of TNFαStandard Error 18.79
ABX464 50 mgTNFα Serum Concentrations100 Percentage of TNFαStandard Error 9.313
ABX464 25 mgTNFα Serum Concentrations100 Percentage of TNFαStandard Error 19
Matching PlaceboTNFα Serum Concentrations100 Percentage of TNFαStandard Error 5.473
Secondary

TNFα Serum Concentrations

Serum samples from patients who received ABX464 (25, 50, or 100 mg) or placebo were collected during 5 visits (Day 1, Day 8, Day 29, Day 57 and Day 113 TNF-alpha was measured using the 8-plex assay on the ELLA Platform. All samples were tested in duplicate at the minimum required dilution. Baseline (Day 1) values are calculated as below: x1/arithmetic mean of baseline values x 100, where the arithmetic mean is defined by (x1 + x2+...+xn)/n (summing all baseline values and dividing by the total number of values n) The post baseline values are calculated as follow: post-baseline TNFα values - Day 1 TNFα values/Day 1 TNFα values)\*100

Time frame: Day 8, Day 29, Day 57 and Day 113

Population: Only samples which were collected have been analyzed

ArmMeasureGroupValue (MEAN)Dispersion
ABX464 100 mgTNFα Serum ConcentrationsDay 898.8 Percent ChangeStandard Error 3.423
ABX464 100 mgTNFα Serum ConcentrationsDay 2999.62 Percent ChangeStandard Error 5.374
ABX464 100 mgTNFα Serum ConcentrationsWeek 8 (Day 57)105.5 Percent ChangeStandard Error 9.675
ABX464 100 mgTNFα Serum ConcentrationsWeek 16 (Day 113)103.7 Percent ChangeStandard Error 7.61
ABX464 50 mgTNFα Serum ConcentrationsDay 2991.30 Percent ChangeStandard Error 4.676
ABX464 50 mgTNFα Serum ConcentrationsWeek 8 (Day 57)95.55 Percent ChangeStandard Error 4.503
ABX464 50 mgTNFα Serum ConcentrationsWeek 16 (Day 113)108.6 Percent ChangeStandard Error 10.61
ABX464 50 mgTNFα Serum ConcentrationsDay 896.77 Percent ChangeStandard Error 5.844
ABX464 25 mgTNFα Serum ConcentrationsWeek 8 (Day 57)97.51 Percent ChangeStandard Error 4.874
ABX464 25 mgTNFα Serum ConcentrationsDay 2992.64 Percent ChangeStandard Error 4.629
ABX464 25 mgTNFα Serum ConcentrationsWeek 16 (Day 113)100.1 Percent ChangeStandard Error 7.194
ABX464 25 mgTNFα Serum ConcentrationsDay 896.42 Percent ChangeStandard Error 4.552
Matching PlaceboTNFα Serum ConcentrationsWeek 16 (Day 113)111.4 Percent ChangeStandard Error 7.725
Matching PlaceboTNFα Serum ConcentrationsDay 29110.2 Percent ChangeStandard Error 10.12
Matching PlaceboTNFα Serum ConcentrationsDay 899.7 Percent ChangeStandard Error 2.739
Matching PlaceboTNFα Serum ConcentrationsWeek 8 (Day 57)102.6 Percent ChangeStandard Error 4.873

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026