Efficacy and Safety of SAR339658 in Patients With Moderate to Severe Ulcerative Colitis

The study period per patient will include up to 4 weeks screening, 8 weeks treatment, 6
weeks post treatment safety follow-up, followed by a long term safety follow-up performed in
the form of a phone interview at 3, 6, 12, 18 and 24 months from the last administration of
the study medication.

After completion of the 8-week treatment phase, patients may be eligible to enter a long
term safety study (LTS12593) for active treatment with SAR339658.

Inclusion criteria:

- Male or Female ≥18 and ≤70 years old

- History of active ulcerative colitis of at least 3 months duration

- Active UC should be confirmed by colonoscopy or flexible sigmoidoscopy during the
screening period within 7 days prior to randomization.

- Moderate to severe ulcerative colitis at time of screening, confirmed by Mayo score
≥6 to 12 and endoscopy subscore of ≥2 despite treatment with immunosuppressants
and/or anti-tumor necrosis factors (TNFs):

- Immunosuppressants: Patient must be on concurrent treatment with or have had an
inadequate response to (did not respond to or lost response to) or be intolerant
to immunosuppressants such as azathioprine, 6-mercaptopurine, or methotrexate.

- AND/OR

- TNF-alpha antagonists: Patient must have had an inadequate response or lost
response or be intolerant to TNF-alpha antagonists

- Fecal calprotectin ≥200mg/kg

- Patients on corticosteroids must be on a stable dose ≥2 weeks prior to screening

- Patients on azathioprine, 6- mercaptopurine or methotrexate must be on treatment for
at least 12 weeks prior to screening; and on a stable dose ≥4 weeks prior to
screening

- Patients on oral 5-aminosalicylates, mesalamine or sulfasalazine must be on a stable
dose for ≥4 weeks prior to screening

- Patients naïve to anti-TNF alpha or non-responder (primary or secondary) or
intolerant to anti-TNF alpha

- Signed written informed consent

Exclusion criteria:

- Patients with Crohn's Disease

- Diagnosis of indeterminate colitis

- Patients with stool sample positive for ova, parasites, or positive culture for
aerobic pathogens including: Aeromonas, Plesiomonas, Shigella, Yersinia,
Campylobacter and E. Coli spp. or positive for Clostridium difficile B toxin in
stools.

- Patients with prior colectomy or anticipated colectomy during their participation in
the study

- Presence of ileal pouch or ostomy

- Fulminant disease or toxic megacolon

- Colonic dysplasia except for adenoma

- Total Parenteral Nutrition

- Cyclosporine, mycophenolate mofetil, sirolimus (rapamycin), thalidomide or tacrolimus
within 2 months prior to screening

- Previous exposure to natalizumab (Tysabri®) or vedolizumab

- Antidiarrheals within 2 weeks prior to screening

- Prednisone >40 mg/day (or equivalent)

- Budesonide >9 mg/day

- Received intravenous corticosteroids within 2 weeks prior to screening or during
screening

- Rectally administered topical 5-aminosalicylate or corticosteroids within 4 weeks
prior to screening

- Received therapeutic enema or suppository, other than required for colonoscopy or
flexible sigmoidoscopy within 4 weeks prior to screening or during screening

- Antibiotics for ulcerative colitis or gastrointestinal infection within 4 weeks prior
to screening

- Patient who has previously participated in any clinical trial of GBR500 / SAR339658

- Patient who has taken other investigational medications within 2 months or 5 half
lives, (whichever is longer) prior to screening

- Use of any biologics for the treatment of ulcerative colitis in the previous 8 weeks
before screening

- Requirement for concomitant treatment that could bias primary evaluation

- Pregnant or breast-feeding women

- Women of childbearing potential not protected by highly effective contraceptive
method of birth control

- Patient with latent or active tuberculosis (TB) defined as:

- Any signs or symptoms suggestive of active TB upon medical history or clinical
examination

- Patients with a positive QuantiFERON TB Gold Test

- Chest radiograph within 3 months prior to the inclusion visit consistent with
prior tuberculosis infection including, but not limited to, apical scarring,
apical fibrosis, or multiple calcified granulomasa. This does not include
non-caseating granulomasa

- Patients with close contact with a person with active tuberculosis

- Patient with a history of listeriosis or tuberculosis (unless it is documented that
they were adequately treated)

- Administration of any live (attenuated) vaccine within 3 months prior to the
screening Visit (eg, varicella-zoster vaccine, oral polio, rabies)

- Positive Hepatitis B surface antigen (HBsAg) or positive Hepatitis B core antibody
(HBcAb); and/or positive Hepatitis C antibody (HCV) at the Screening Visit

- Prior opportunistic infections within 6 months prior to screening or while receiving
anti-TNF treatment

- History of a hypersensitivity reaction, other than localized injection site reaction,
to any biological molecule

- History or any current signs of demyelinating disease or any neurological disease
that can by the opinion of Investigator interfere with study safety assessments
including assessment for progressive multifocal leukoencephalopathy

- Patients with bleeding disorders or known platelet dysfunction

The above information is not intended to contain all considerations relevant to a
patient's potential participation in a clinical trial.