A Study to Assess the Efficacy of RO5459072 in Participants With Primary Sjogren's Syndrome

Inclusion Criteria:

- A diagnosis of primary Sjogren's syndrome according to the revised American-European
Consensus Group (AECG) criteria

- ESSDAI score greater than or equal to (>/=) 5

- ESSPRI score >/=5

- Elevated serum titers of anti-Sjogren's-syndrome-related antigen A (anti-SSA) and/or
anti-Sjogren's-syndrome-related antigen B (anti-SSB) antibodies at screening

- Negative pregnancy test at screening and baseline (for women only)

- Willing to comply with the study procedures and restrictions, including measures to
prevent pregnancy and restrictions on sperm donation

Exclusion Criteria:

- A diagnosis of secondary Sjogren's syndrome according to the revised AECG criteria

- Severe complications of Sjogren's syndrome

- Systemic immunosuppressant therapy, cyclophosphamide, or B-cell depleting therapy
within 6 months prior to the screening visit

- Corticosteroid therapy exceeding 7.5 mg prednisone equivalents per day

- A positive test result for hepatitis B (HBV), hepatitis C (HCV), or human
immunodeficiency virus (HIV), or tuberculosis, or any other active viral, fungal,
yeast or bacterial infection at screening

- A history suggesting reduced immune function or any other conditions predisposing
participants to serious infection

- A history of lymphoma, myeloma or monoclonal gammopathy of unknown significance
(MGUS), or any other malignancies within the past 5 years

- A diagnosis of fibromyalgia or significant depression

- Having any concomitant disease or condition that could interfere with the conduct of
the study, or that would pose an unacceptable risk to the individual

- Participation in an investigational drug or device study within 3 months prior to
screening

- Inability to comply with the study protocol for any other reason

- Women who are lactating, breastfeeding or planning to nurse

- Using other prohibited medication (moderate or potent inhibitors of CYP3A4; strong
inducers of CYP3A4; strong inhibitors of the transporter P-glycoprotein [P-gp];
sensitive substrates of CYP3A4 with a narrow therapeutic index)