Single-dose Study to Describe the Pharmacodynamics (PD) and Safety of Sarilumab (REGN88/SAR153191) and Tocilizumab in Adults With Rheumatoid Arthritis (RA)

Study Overview
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Brief Summary
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The main purposes of this study are to describe the pharmacodynamic effects, safety and pharmacokinetics of a single dose of sarilumab.

Conditions
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Rheumatoid Arthritis

Intervention / Treatment
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* Drug: Sarilumab
* Drug: Tocilizumab


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with RA as defined by the 2010 revised American College of Rheumatology (ACR) ACR Class I-III functional status, based on the 1991 revised criteria Treated for a minimum of 12 weeks with Methotrexate with a stable dose of MTX for at least 8 weeks prior to screening visit Exclusion Criteria: Patients less than 18 years of age or minimum legal age Prior treatment with any biologic anti-Interleukin 6 (IL-6) or IL-6 Receptor (IL-6R) antagonists Use of parenteral corticosteroids or intra-articular corticosteroids within 4 weeks prior to screening Use of oral corticosteroids in a dose higher than prednisone 10 mg or equivalent per day, or a change in dosage within 4 weeks prior to randomization Participation in any clinical research study that evaluated an investigational drug or therapy within 5 half-lives or 60 days of the screening visit, whichever is longer Treatment with oral/ biologic DMARDs (disease-modifying antirheumatic drugs), other than MTX, within a certain amount of time prior to screening visit Active or suspected TB or at high risk of contracting TB Fever, or chronic, persistent, or recurring infections requiring active treatment HIV positive Note: The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial therefore not all inclusion/ exclusion criteria are listed.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Sarilumab - dose 1<br>Single subcutaneous (SC) injection of Sarilumab, dose 1, plus methotrexate background treatment (dispensed and dosed according to local practice) | Drug: Sarilumab<br> <br> * Other names: SAR153191;|
| Experimental: Sarilumab - dose 2<br>Single SC injection of Sarilumab, dose 2, plus methotrexate background treatment (dispensed and dosed according to local practice) | Drug: Sarilumab<br> <br> * Other names: SAR153191;|
| Active Comparator: Tocilizumab - dose 1<br>Single intravenous (IV) administration of Tocilizumab, dose 1, plus methotrexate background treatment (dispensed and dosed according to local practice) | Drug: Tocilizumab<br> <br> |
| Active Comparator: Tocilizumab - dose 2<br>Single IV administration of Tocilizumab, dose 2, plus methotrexate background treatment (dispensed and dosed according to local practice) | Drug: Tocilizumab<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| PD parameters | Pharmacodynamic (PD) parameters, what a drug does to the body, will be collected from baseline through week 4: the time to nadir (or peak) change from baseline area under the curve (AUC) | baseline through week 4 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of TEAEs | Percentage of patients with treatment-emergent adverse events (TEAEs) from baseline through end of study (week 6). | baseline through week 6 | 
| PK parameters | Pharmacokinetic (PK) parameters, what the body does to a drug, will be collected from baseline through week 4: AUC CL (clearance) Cmax (the peak concentration) t1/2 (observed terminal half-life) | baseline through week 4 |