To Evaluate the Immunogenicity and Safety of Sarilumab Administered as Monotherapy in Patients With Rheumatoid Arthritis (RA)

Total study duration is up to 34 weeks: Up to 4-week screening period, 24-week open-label
treatment phase, 6-week post-treatment observation. After completion of the treatment phase
of this study, patients are eligible to enter a long term safety study (LTS11210 -
SARIL-RA-EXTEND) for continuous treatment with sarilumab (SAR153191 [REGN88]).

Inclusion criteria:

- Diagnosis of rheumatoid arthritis (RA) ≥ 3 months.

- Moderately to severely active rheumatoid arthritis.

- Patients who per investigator judgment were incomplete responders to at least 12
weeks of an adequate dose of continuous treatment with or who were intolerant of one
or a combination of non-biologic disease modifying anti-rheumatic drugs (DMARDs).

Exclusion criteria:

- Patients < 18 years of age.

- Past history of, or current, autoimmune or inflammatory systemic or localized joint
disease(s) other than RA.

- History of juvenile idiopathic arthritis or arthritis onset prior to age 16.

- Severe active systemic RA, including but not limited to vasculitis, pulmonary
fibrosis, and/or Felty's syndrome.

- Prior treatment with any biologic anti-interleukin 6 (IL-6) or IL-6 receptor (IL-6R)
antagonist therapies.

- Treatment with prednisone > 10 mg or equivalent per day, or change in dosage within 4
weeks prior to randomization.

- New treatment with or dose-adjustment of on-going nonsteroidal anti-inflammatory drug
(NSAIDs) or cyclooxygenase-2 (COX-2) inhibitors within 4 weeks prior to
randomization, except for the use of low-dose acetylsalicylic acid for cardiovascular
diseases.

- Use of parenteral glucocorticoids or intraarticular glucocorticoids injection within
4 weeks prior to randomization.

- Prior treatment with a Janus kinase (JAK) inhibitor (tofacitinib).

- New treatment or dose-adjustment to on-going medication for dyslipidemia, such as
statin, within 6 weeks prior to randomization.

- Participation in any clinical research study evaluating another investigational drug
or therapy within 5 half-lives or 60 days of first dose of study drug administration,
whichever is longer.

- Patients with a history of malignancy other than adequately-treated carcinoma in-situ
of the cervix, nonmetastatic squamous cell or basal cell carcinoma of the skin,
within 5 years prior to the randomization visit. Nonmalignant lymphoproliferative
disorders are also excluded.

- Patients with active tuberculosis or untreated latent tuberculosis infection.

- Pregnant or breast feeding women.

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