Study Evaluating the Long-Term Safety and Efficacy of ABX464 in Patients With Moderate to Severe Rheumatoid Arthritis

A Follow-up Phase 2a Open-label Study to Evaluate the Long-term Safety and Efficacy Profile of ABX464 in Patients With Moderate to Severe Active Rheumatoid Arthritis

A phase 2a open-label study to evaluate the long-term safety and efficacy of ABX464 50mg as maintenance therapy in patients with moderate to severe rheumatoid arthritis.

Study Overview

• Status: Completed
• Conditions: Rheumatoid Arthritis
• Intervention / Treatment: Drug: ABX464

Detailed Description

This Phase 2a open-label study aims at investigating the long-term safety and efficacy of an oral dose of ABX464 in patients who have been previously enrolled in the ABX464-301 clinical study and who are willing to continue their treatment.

All patients will receive ABX464 given at 50mg o.d. irrespectively of their previous treatment received in the ABX464-301 study (i.e. ABX464 or Placebo).

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.

Patients will be treated with ABX464 for a period of 52 weeks. If they achieve a clinical response on Week 52 (defined as DAS28-CRP ≤ 2,6 for anti-TNFα naïve patients or DAS-28-CRP ≤ 3,2 for patients previously treated by anti-TNFα), they will be eligible to continue treatment for up to 104 weeks.Patients will be followed up at week , week 2 and then, on a monthly basis the first year (up to W52), and quaterly the second year (up to W104).

• Study Type: Interventional
• Enrollment (Actual): 40
• Phase: Phase 2

Contacts and Locations

Study Locations

• Belgium
  • Brussels, Belgium
    • Cliniques Universitaires Saint-luc
  • Ghent, Belgium
    • UZ Gent
• France
  • Brest, France
    • CHU de BREST - Hôpital Cavale Blanche
  • Montpellier, France
    • CHU de Montpellier - Hôpital Lapeyronie
  • Orléans, France
    • CHR d'Orléans
• Hungary
  • Budapest, Hungary
    • Complex Medical Centre - Déli Klinika
  • Miskolc, Hungary
    • CRU Hungary Ltd.
  • Székesfehérvár, Hungary
    • CMed Rehabilitacios es Diagnosztikai Kozpont
• Poland
  • Bialystok, Poland
    • ClinicMed Daniluk, Nowak Sp. J.
  • Krakow, Poland
    • Pratia MCM
  • Lublin, Poland
    • Zespół Poradni Specjalistycznych REUMED
  • Nadarzyn, Poland
    • NZOZ Lecznica MAK-MED S.C.
  • Poznan, Poland
    • Medyczne Centrum Hetmańska
  • Warsaw, Poland
    • National Institute of Geriatrics

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 76 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patients previously enrolled in the ABX464-301 clinical study who have completed the initial 12 weeks of treatment period;

Criteria that should be met by patients at week 52 to be eligible for 52 additional weeks of study treatment:

▪ Patients should be in clinical response. Clinical response is defined as: DAS28-CRP ≤ 2,6 for anti-TNFα naïve patients or DAS-28-CRP ≤ 3,2 for patients previously treated by anti-TNFα.

Exclusion Criteria:

• Any condition, which in the opinion of the investigator, could compromise the patient's safety or adherence to the study protocol

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: ABX464 50 mg; All subjects will receive ABX464 administered at 50 mg o.d for an overall period of 2 years (104 weeks)	Drug: ABX464; All subjects will receive ABX464 administered at 50 mg o.d for an overall period of 2 years (104 weeks).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of treatment-emergent adverse events in the ABX464 treated Patients, categorized by severity	Incidence of adverse events emerging during the treatment	through study completion (average of 104 weeks)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of patients achieving Low Disease Activity (LDA)	Low Disease Activity (LDA) is defined as DAS28-ESR <=3.2	Week 4, Week 12, Week 24, Week36, Week 52, Week 65, Week 78, Week 91 and Week 104
Proportion of patients achieving American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) Boolean remission	The ACR/EULAR boolean-based remission is a validated criteria based on: Tender/painful Joint Count (28), Swollen Joint Count (28), C-Reactive Protein, patient global assessment of disease, All ≤ 1	Week 4, Week 12, Week24, Week36, Week 52, Week 65, Week 78, Week 91 and Week 104
Proportion of patients achieving Simplified Disease Activity Score (SDAI) remission	The SDAI remission is considered achieved if the SDAI score ≤ 3.3	Week 4, Week 12, Week 24, Week36, Week 52, Week 65, Week 78, Week 91 and Week 104
Proportion of patients achieving Clinical Disease Activity (CDAI) remission	The CDAI remission is considered achieved if the CDAI score ≤ 2.8	Week 4, Week 12, Week 24, Week36, Week 52, Week 65, Week 78, Week 91 and Week 104
Proportion of patients achieving ACR20/50/70 response	The categorical American College of Rheumatology 20% or 50% or 70% (ACR20/50/70) response is a validated index of rheumatoid arthritis disease activity, defined by the number of patients who achieved at least 20% or 50% or 70% improvement in the ACR response.	Week 4, Week 12, Week 24, Week36, Week 52, Week 65, Week 78, Week 91 and Week 104
Proportion of patients achieving categorical Disease Activity Scores (DAS) (measured on 28 joints) - C-Reactive Protein (DAS28-CRP) response	Proportion of patients achieving categorical Disease Activity Score (DAS) DAS28-C-Reactive Protein (CRP) [DAS28-CRP] response will be measured as moderate/good European League Against Rheumatism (EULAR) response	Week 4, Week 12, Week 24, Week36, Week 52, Week 65, Week 78, Week 91 and Week 104
Time to onset of the Low Disease Activity (LDA) remission	time when DAS28-ESR <=3.2	up to 104 weeks
Time to onset of the American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) Boolean remission	The ACR/EULAR remission is a validated criteria based on: Tender/painful Joint Count (28), Swollen Joint Count (28), C-Reactive Protein, patient global assessment of disease, All ≤ 1. Time to onset will be when this criteria will be ≤ 1	up to 104 weeks

Collaborators and Investigators

• Sponsor: Abivax S.A.
• Investigators: Study Chair: Laurence Desroys du Roure, PharmD, Abivax S.A.

Study record dates

Study Major Dates

• Study Start (Actual): October 25, 2019
• Primary Completion (Actual): January 23, 2023
• Study Completion (Actual): January 23, 2023

Study Registration Dates

• First Submitted: August 6, 2019
• First Submitted That Met QC Criteria: August 7, 2019
• First Posted (Actual): August 8, 2019

Study Record Updates

• Last Update Posted (Estimated): November 17, 2025
• Last Update Submitted That Met QC Criteria: November 14, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: moderate to severe Rheumatoid Arthritis
• Additional Relevant MeSH Terms: Musculoskeletal Diseases; Arthritis; Joint Diseases; Rheumatic Diseases; Connective Tissue Diseases; Autoimmune Diseases; Immune System Diseases; Skin and Connective Tissue Diseases; Arthritis, Rheumatoid; ABX464
• Other Study ID Numbers: ABX464-302

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No