A Study to Evaluate the Safety, Tolerability, Pharmacokinetics (PK), Proof of Mechanism of GSK2618960 in Primary Sjögren's Syndrome (pSS)

A Two Part Phase IIa Study, to Evaluate the Safety and Tolerability, Pharmacokinetics, Proof of Mechanism and Potential for Efficacy of an Anti-IL-7 Receptor-α Monoclonal Antibody (GSK2618960) in the Treatment of Primary Sjögren's Syndrome

This study aims to evaluate the safety, tolerability and PK of repeat dose administration of GSK2618960 in the treatment of pSS. The study will contain two parts, Part I will be open label and Part II will be randomized, double-blind. The minimum duration of Part I & Part II of the study will be 26 and 32 weeks respectively.

Inclusion Criteria:

• Part I and Part II: Male and females aged 18-70
• Part I and Part II: pSS diagnosis according to the American-European Consensus Group Criteria
• Part I and Part II: Documented previous biopsy evidence of salivary gland inflammation consistent with pSS and/or documented history of anti-Ro and/or anti-La antibodies
• Part II: Has any of the following abnormalities at screening: hypergammaglobulinaemia [serum Immunoglobulin G (IgG) greater than or equal to 16 gram per liter (g/L); Presence of Rheumatoid factor (RF); Anti Nuclear Antibodies (ANA) titer greater than or equal to 320:1.
• Stimulated whole salivary flow greater than 0.1 milliliter per minute (mL/min) at screening.
• Symptomatic oral dryness greater than or equal to 5 out of 10 on Visual Analogue Scale (VAS) scale and/or Schirmer test less than 10 millimeter (mm) at screening.

Exclusion Criteria:

• Part I and II: Secondary Sjögren's Syndrome
• Part I and II: Receiving cyclophosphamide, other biologic, immunosuppressive or immunomodulatory treatments
• Part I and II: Active infections, or history of recurrent infections
• Part I and II: History of significant medical illness
• Part I and II: History of lymphoma