A Phase 2 interventional study of SAR441566 and SAR441566 matching Placebo in Crohn's Disease, sponsored by Sanofi. Terminated at 141 sites in 24 countries. Open to participants aged 18 Years to 75 Years. Per ClinicalTrials.gov, last updated 2026-10-13.
Sponsored by Sanofi · Phase 2, Interventional, and Treatment
Business decision.
This is a phase 2, multinational, multicenter, randomized, double-blind, placebo-controlled, dose ranging study to evaluate the efficacy and safety of SAR441566 in adults with moderate to severe Crohn's Disease (CD). The primary objective of this study is to assess the efficacy of different doses of SAR441566 compared with placebo in participants with moderate to severe CD.
This study will have an anticipated duration of up to 59 weeks which will include a screening period of 4 weeks (+7 calendar days if needed), followed by the Main Study (MS) treatment period, lasting 52 weeks, and a 2-week follow-up period after end of treatment for participants not enrolling in the Long Term Safety (LTS) study. The MS period includes a Double-Blind (DB) treatment period with 12 weeks of induction followed by 40 weeks of maintenance.
Additionally, an Open Label (OL) period of up to 40 weeks will be offered to eligible participants. The combined duration of the DB maintenance and OL periods cannot exceed 40 weeks, depending on when participants switch.
1,992 studies on the registry are indexed under Crohn Disease; 478 are open to participants now.
This study's enrollment of 105 is above the median of 67 across 1,260 interventional studies indexed under Crohn Disease.
Browse Crohn Disease 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.
Participants are eligible to be included in the study only if all of the following criteria apply:
Confirmed diagnosis of moderate to severe CD as assessed by:
Exclusion Criteria:
Participants are excluded from the study if any of the following criteria apply:
The above information is not intended to contain all considerations relevant to a patient's 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.
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.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
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.
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.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
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.
Participants will receive SAR441566 dose 1.
Drug: SAR441566
Participants will receive SAR441566 dose 2.
Drug: SAR441566
Participants will receive SAR441566 dose 3.
Drug: SAR441566
Participants will receive SAR441566 matching placebo.
Drug: SAR441566 matching Placebo
Pharmaceutical form: Tablet Route of administration: Oral
Pharmaceutical form: Tablet Route of administration: Oral
Proportion of participants achieving endoscopic response
Endoscopic response is defined as ≥50% reduction from baseline in centrally read Simple Endoscopic Score for Crohn's Disease (SES-CD). The SES-CD evaluates 4 endoscopic variables (ulcer size, ulcerated surface, affected surface, and narrowing, each on a scale from 0 (none) to 3 in 5 segments assessed during ileocolonoscopy (ileum, right colon, transverse colon, sigmoid and left colon, and rectum). The total score is the sum of the 4 endoscopic variable scores and ranges from 0 to 56, where higher scores indicate more severe disease.
Time frame: Week 12
Proportion of participants achieving clinical remission based on Crohn's Disease Activity Index (CDAI)
CDAI clinical remission is defined as CDAI score \<150. CDAI is a composite instrument that includes participant symptoms evaluated over 7 days (abdominal pain, stool frequency and general well-being), as well as presence of complications (arthritis/arthralgia, iritis/uveitis, erythema nodosum/pyoderma gangrenosum/aphthous stomatitis, anal fissure/fistula/abscess, other fistula, and fever), the use of antidiarrheal medicines, presence of an abdominal mass, hematocrit, and body weight. These items are scored individually, weighted, and do not contribute equally to the overall score. The CDAI is derived from summing up the weighted individual scores of eight items. CDAI approximately ranges from 0 to 600 with higher scores indicating more severe disease.
Time frame: Week 12
Proportion of participants achieving Patient-Reported Outcome (PRO-2) remission
PRO 2 remission is defined as the unweighted CDAI component of daily abdominal pain (AP) score ≤1, and the unweighted CDAI component of daily average stool frequency (SF) score ≤3 (ie, AP ≤1 and SF ≤3 and no worsening from baseline).
Time frame: Week 12
Proportion of participants achieving both clinical remission and endoscopic response
Clinical remission and endoscopic response based on CDAI \<150 and ≥50% reduction from baseline in centrally read Simple Endoscopic Score for Crohn's Disease (SES-CD)
Time frame: Week 12
Proportion of participants achieving endoscopic remission based on centrally read SES-CD
Endoscopic remission is defined as a centrally read SES-CD ≤4 points (SES-CD ≤2 points for isolated ileal disease) and a SES-CD decrease from baseline ≥2 points with no SES-CD sub score \>1 point
Time frame: From Baseline to Week 12
Proportion of participants achieving CDAI clinical response
CDAI clinical response is defined as a CDAI reduction from baseline ≥100 points.
Time frame: From Baseline to Week 12
Proportion of participants achieving Inflammatory Bowel Disease Questionnaire (IBDQ) remission
IBDQ remission is defined as IBDQ total score ≥170 points. The Inflammatory Bowel Disease Questionnaire (IBDQ) is used to assess health-related quality of life (HRQoL) in patients with inflammatory bowel disease. It consists of 32 questions evaluating bowel and systemic symptoms, as well as emotional and social functions. Each question is answered on a scale from 1 (worst) to 7 (best). The total score ranges from 32 to 224 with higher scores indicating better health-related quality of life.
Time frame: Week 12
Proportion of participants achieving IBDQ response
IBDQ response defined as an improvement of IBDQ scores by 27 points or more at Week 12 compared with baseline
Time frame: From baseline to Week 12
Change from baseline in the IBDQ scores
The total IBDQ score ranges from 32 to 224 which indicates better quality of life. A positive change from Baseline indicates improvement.
Time frame: From Baseline to week 12
Plasma pre-dose concentrations of SAR441566 at selected visits
Time frame: Up to week 52
Plasma post-dose concentrations of SAR441566 at selected visits
Time frame: Up to week 52
Number of participants experiencing any TEAEs
Any TEAEs, including any serious opportunistic infections, psoriasiform skin lesions or other immune mediated phenomena during double-blind (DB) induction and maintenance treatment period
Time frame: Up to week 52
Number of participants experiencing any TEAEs
Any TEAEs, including any serious opportunistic infections, psoriasiform skin lesions or other immune mediated phenomena during open-label treatment period
Time frame: From week 12 to week 52
Showing the first 100 of 141 sites across 24 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 Dec 2024 to primary completion in Jul 2026, 19 months.
How these figures are worked out, and which studies are left out of them.
Business decision.
Business decision.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is terminated, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Balinatunfib