A Study of Nipocalimab in Adults With Primary Sjogren's Syndrome (pSS)

The purpose of this study is to evaluate the efficacy and safety of nipocalimab in participants with primary Sjogren's syndrome (pSS) versus placebo.

Sjogren's syndrome is a chronic, progressive autoimmune disease of unclear etiology typically originating in exocrine glands and capable of affecting the function of almost any organ system in the body. Nipocalimab is a fully human aglycosylated immunoglobulin (Ig)G1 monoclonal antibody designed to selectively bind, saturate, and block the IgG binding site on the endogenous neonatal fragment crystallizable receptor (FcRn). Nipocalimab blocks the binding site for IgG on FcRn, leads directly to increased IgG catabolism and a decrease in circulating IgG antibody concentrations, including pathogenic IgG antibody concentrations, and directly inhibits inflammatory cellular responses to these pathogenic IgG. Therefore, Nipocalimab may successfully treat pSS and improve disease manifestations. The study will consist of Screening Period (less than or equal to \[\<=\] 6 Weeks), Double-blind Treatment Period (24 Weeks), and a Follow-up Period (6 Weeks). Key safety assessments will include adverse events (AEs), serious adverse events (SAEs), adverse events of special interests (AESIs), clinical laboratory safety tests (hematology, chemistry, urinalysis, and lipid profile) and vital signs. The total duration of the study is up to 36 weeks.

Eligibility Criteria:
Inclusion Criteria:

* Meets classification criteria for primary Sjogren's syndrome (pSS) by the 2016 American College of Rheumatology (ACR) / European League Against Rheumatism (EULAR) at the time of screening, and was diagnosed with pSS no less than 26 weeks prior to screening
* At screening is seropositive for antibodies to pSS-associated antigen A (Ro/Sjogren's syndrome-related antigen A \[SSA\])
* Total Clinical European League Against Rheumatism Sjogren's Syndrome Disease Activity Index (clinESSDAI) score greater than or equal to (\>=) 6
* At least one abnormal laboratory marker of pSS-related inflammatory disease activity, and at least low activity in one or more specified European League Against Rheumatism Sjogren's Syndrome Disease Activity Index (ESSDAI) domains
* It is recommended that participants are up to date on all age-appropriate vaccinations prior to screening as per routine local medical guidelines. For study participants who received locally-approved (and including emergency use-authorized) coronavirus disease 2019 (COVID-19) vaccines recently prior to study entry, applicable local vaccine labelling, guidelines, and standards-of-care for participants receiving immune-targeted therapy will be followed when determining an appropriate interval between vaccination and study enrollment

Exclusion Criteria:

* Has any confirmed or suspected clinical immunodeficiency syndrome not related to treatment of his/her pSS or has a family history of congenital or hereditary immunodeficiency unless confirmed absent in the participant
* Comorbidities (for example, asthma, chronic obstructive pulmonary disease) which have required 3 or more courses of systemic glucocorticoids within the previous 12 months
* Has any unstable or progressive manifestation of pSS that is likely to warrant escalation in therapy beyond permitted background medications and/or has severely active pSS
* Has received oral cyclophosphamide within 3 months or intravenous (IV) cyclophosphamide within 6 months prior to first administration of study intervention
* Has Sjogren's syndrome overlap syndromes where another confirmed autoimmune rheumatic or systemic inflammatory condition (for example, rheumatoid arthritis \[RA\], systemic lupus erythematosus \[SLE\], scleroderma, inflammatory bowel disease \[IBD\]) is the primary diagnosis or has clinical manifestations that, in the opinion of the investigator, or the sponsor or sponsor's representative, are likely to interfere with the investigator's ability to assess pSS manifestations