A Study to Evaluate the Safety, Tolerability and Pharmacokinetics of Multiple Subcutaneous Injections of ABT-122 in Subjects With Rheumatoid Arthritis

This is a phase 1, randomized, double-blind, placebo-controlled, multiple ascending dose
study. Twenty-four subjects with Rheumatoid Arthritis will be selected to participate.
Subjects will be randomized to receive either ABT-122 or placebo. ABT-122 or placebo will be
administered as subcutaneous (under the skin) injections in three dosing groups.

Inclusion Criteria:

- Diagnosis of Rheumatoid Arthritis (RA) > 3 months.

- On methotrexate (MTX) therapy => 3 months and on a stable dose for at least 4 weeks.

- Except for MTX, must have discontinued all disease-modifying antirheumatic drugs
(DMARDs) for at least 3 months or 5 half-lives, whichever is longer.

- Body Mass Index (BMI) is 19 to 38, inclusive.

- Other than RA, subjects should be in good general health.

Exclusion Criteria:

- Evidence of anti-ABT-122 antibody on a serum sample taken at Screening.

- History of significant allergic reaction; or history of anaphylactic reaction to any
agent; or history of major reaction to any IgG containing product.

- History of persistent chronic or active infection(s) requiring hospitalization or
treatment with intravenous or oral anti-microbials/antibiotics within the past 30
days.

- History or evidence of active tuberculosis (TB) or the subject has evidence of risk
factor for latent TB.

- Subject has any medical condition or illness other than RA that is not well controlled
with treatment.