A Phase 2 interventional study of SAR441566 and Placebo in Rheumatoid Arthritis, sponsored by Sanofi. Completed at 102 sites in 19 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-07-11.
Sponsored by Sanofi · Phase 2, Interventional, and Treatment
This is a parallel group, Phase 2, randomized, double-blind, placebo controlled, 5-arm, international, multicenter, 12-week proof of concept, dose finding study. It is designed to assess efficacy and safety of treatment with SAR441566 for 12 weeks. It will be conducted in male and female adult participants with moderate-to-severe rheumatoid arthritis (RA) not adequately controlled on methotrexate (MTX) and biologic/targeted synthetic disease modifying anti-rheumatic drug (DMARD) naive.
Study treatment includes investigational medicinal product (IMP: SAR441566 or placebo) added-on to a background therapy of MTX.
Study details include a run-in period (4 to 6 weeks) before randomization to determine eligibility, a treatment period (12 weeks ± 3 days) and a post-treatment period (safety follow-up) (2 weeks ± 3 days). The total number of scheduled study visits will be 8.
The overall study duration for each participant will be approximately up to 149 days.
3,332 studies on the registry are indexed under Arthritis, Rheumatoid; 443 are open to participants now.
This study's enrollment of 264 is above the median of 96 across 2,220 interventional studies indexed under Arthritis, Rheumatoid.
Browse Arthritis, Rheumatoid studies →Sanofi is the lead sponsor of 1,557 studies on the registry; 91 are open to participants now.
Of its 205 completed or terminated interventional studies of FDA-regulated products, 123 (60%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Moderate-to-severely active RA, defined as:
Continuous treatment with MTX for at least 12 consecutive weeks prior to randomization and with stable dose/means of administration at least 6 weeks prior to the screening visit
Exclusion Criteria:
History of diagnosis of demyelinating disease such as but not limited to:
The above information is not intended to contain all considerations relevant to a potential participation in a clinical trial.
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
NYHA class (heart failure)
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Live vaccines
Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
QT and QTc
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participant will receive dose regimen A of SAR441566 for 12 weeks
Drug: SAR441566
Participant will receive dose regimen B of SAR441566 for 12 weeks
Drug: SAR441566
Participant will receive dose regimen C of SAR441566 for 12 weeks
Drug: SAR441566
Participant will receive dose regimen D of SAR441566 for 12 weeks
Drug: SAR441566
Participant will receive SAR441566-matching placebo for 12 weeks
Drug: Placebo
Tablet
Tablet
Proportion of participants achieving at least 20% improvement from baseline in the American College of Rheumatology (ACR) score at week 12
ACR20 response criteria is a dichotomous composite endpoint indicating the proportion of participants with at least 20 percent improvement in the number of tender and swollen joints, and in three out of the remaining five ACR core-set measures: patient pain (VAS, No pain to Severe Pain), Patient Global Assessment of disease activity (VAS, Very well to Very Poor), physician global assessment of disease activity (VAS, Very good to Very bad), physical functioning assessment (Health Assessment Questionnaire-Disability Index \[HAQ-DI\]), and acute phase reactants (ESR or CRP mg/dl; in this study CRP will be used). ACR response is scored as a percentage improvement, comparing disease activity at two discrete time points. ACR20 is ≥ 20% improvement.
Time frame: Baseline to Week 12
Change from baseline in Disease activity score - C-reactive protein (DAS-28 CRP) at week 12
The DAS28-CRP is a composite endpoint. DAS28-CRP is comprised of clinical assessment of 28 swollen joint count (SJC)/ tender joint count (TJC), patient assessment of global disease activity and CRP mg/dL. It is a continuous measure allowing for measurement of absolute change in disease burden and percentage improvement. The DAS28 can be calculated using the following formula: DAS28 = 0.56 x 28TJC + 0.28 x 28SJC + 0.36 x Log(CRP+1) + 0.014 x GH + 0.96 The DAS28 provides a number indicating the current activity of the RA. A DAS28 above 5.1 means high disease activity, whereas a DAS28 below 3.2 indicates low disease activity and a DAS28 below 2.6 means disease remission.
Time frame: Baseline to Week 12
Proportion of participants achieving at least 50% improvement from baseline in the ACR score at week 12
ACR response is scored as a percentage improvement, comparing disease activity at two discrete time points. ACR50 is ≥ 50% improvement. ACR50 responders include ACR20 responders
Time frame: Baseline to week 12
Number of participants with Treatment-Emergent Adverse Events (TEAEs), serious AEs (SAEs), and AEs of special interest (AESIs)
Incidence of TEAEs, SAEs, and AESIs
Time frame: Baseline to week 14
Plasma pre-dose concentrations of SAR441566
Time frame: Week 2 to week 12
Plasma post-dose concentrations of SAR441566
Time frame: Week 0 to week 12
Showing the first 100 of 102 sites across 19 countries. Choose a country and city above to see the rest.
Plan to share: Yes — Qualified researchers may request access to patient level data and related study documents including the clinical study report, study protocol with any amendments, blank case report form, statistical analysis plan, and dataset specifications. Patient level data will be anonymized, and study documents will be redacted to protect the privacy of trial participants. Further details on Sanofi's data sharing criteria, eligible studies, and process for requesting access can be found at: https://vivli.org
No publications or documents are linked to this record.
Ran from Nov 2023 to primary completion in Jun 2025, 19 months.
Of 116 industry-sponsored phase 2 interventional studies under Arthritis, Rheumatoid, half reached primary completion within 17 months of starting (the median), counting those still running; a quarter within 13 and three quarters within 24. This study's 19 months is above that.
Counting every sponsor, half of 158 studies reached it within 18 months; a quarter within 13 and three quarters within 30.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in Jul 2025. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Balinatunfib