This is a first-in-human study to investigate the safety, tolerability, pharmacokinetics, and pharmacodynamics of single intravenous and subcutaneous doses of CFZ533 in healthy subjects and intravenous doses in rheumatoid arthritis patients.

This was a Healthy Volunteer only study originally, but after an amendment to protocol, rheumatoid arthritis patients will be starting 7-Mar-2014 and thus, the protocol is now registered.

Inclusion Criteria (for healthy volunteers):

1. Healthy male and surgically sterilized or post-menopausal female subjects 18 to 55 years of age (for Cohort 9 only, subjects must be of Chinese descent)
2. Vital signs (systolic and diastolic blood pressure and pulse rate) should be within normal limits
3. Weight 50-150 kg and a body mass index (BMI) 18-32 kg/m2

Inclusion Criteria (for rheumatoid arthritis patients):

1. Healthy male and surgically sterilized or post-menopausal female subjects 18 to 55 years of age
2. Fulfilled 2010 ACR/EULAR classification criteria for RA per Investigator
3. Treatment with a stable oral RA treatment regimen for ≥ 4 weeks before randomization
4. Systemic corticosteroids allowed if on a stable dose (≤ 10 mg/day of prednisone or equivalent) ≥ 4 weeks prior to randomization
5. Subjects taking NSAIDs (COX-1 or COX-2 inhibitors) as part of their RA therapy must be on a stable dose for at least 4 weeks before randomization

Exclusion Criteria (for healthy volunteers):

1. History of hypersensitivity to vaccines, the study drug, or to drugs of similar chemical classes (i.e., biologic agents)
2. Abnormal hematology, coagulation or inflammatory lab results
3. History or evidence of tuberculosis.

Exclusion Criteria (for rheumatoid arthritis patients):

1. Use of anti-TNF or other biologics in previous 3 months
2. Any intra-articular injection therapy (e.g., corticosteroid, hyaluronan) required for treatment of acute RA flare within 4 weeks before randomization
3. Previous treatment with a B cell-depleting biologic agent or any other immunomodulatory biologic agent within 5 half-lives (experimental or approved)
4. Current treatment with cyclophosphamide
5. Autoimmune disease other than RA
6. Adult juvenile rheumatoid arthritis
7. RA functional status class IV according to the ACR 1991 revised criteria

Other protocol-defined inclusion/exclusion criteria may apply