A Study of the Efficacy and Safety of Belimumab in Adults With Interstitial Lung Disease Associated With Connective Tissue Disease

Inclusion criteria:

• Participants with persistent/worsening active inflammatory disease who have failedto achieve their treatment goal, i. e., those who have experience lack of expectedtreatment benefit (clinically meaningful improvement in FVC), fail to demonstratesustained lung function stability or continue to experience worsening of ILD despiteinitiation of standard therapy or failed to tolerate standard therapy.

• Documented diagnosis of rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), idiopathic inflammatory myopathy (IIM; including polymyositis,dermatomyositis, anti-synthetase syndrome), Sjogren's syndrome (pSS), or mixedconnective tissue disease (MCTD) in accordance with internationally recognizedclassification criteria

• Diagnosis of inflammatory and/or fibrotic ILD on High Resolution Computed Tomography (HRCT) with a total disease extent of greater than or equal to (≥) 10% of the wholelung

• Evidence of persistent active/worsening ILD

• Must be currently receiving stable standard therapy to manage ILD and/or underlyingCTD, or to have failed or failed to tolerate standard therapy.

• Participant is capable and willing to self-administer the study medication or has acaregiver who is capable and willing to administer the study medication throughoutthe study

• A female participant is eligible to participate if she is not pregnant orbreastfeeding, and one of the following conditions applies:

• Is a woman of nonchildbearing potential (WONCBP) OR

• Is a Woman of childbearing potential (WOCBP) and using a contraceptive methodthat is highly effective, with a failure rate of less than (<)1%

• Capable of giving signed informed consent

Exclusion Criteria:

• Diagnosis of ILD other than CTD-ILD.

• Primary diagnosis of Systemic Sclerosis (SSc).

• Participants with rapidly progressive disease (absolute drop of 10% or more of FVCbetween screening and baseline visit and/or recent pulmonary hospitalization).

• FVC ≤ 45% of predicted, or a Diffusing Capacity of the lung for Carbon Monoxide (DLco) (corrected for hemoglobin) ≤ 40% of predicted at screening as confirmed bycentral reader

• History or presence of diffuse alveolar hemorrhage (DAH) or other confoundingpulmonary disease, signs, or symptoms

• Pulmonary arterial hypertension requiring therapy, as determined by the investigatorat, or prior to first day of dosing (Day 1)

• Dependence on continuous oxygen supplementation

• History or presence of cardiovascular, respiratory, hepatic, renal,gastrointestinal, endocrine, hematologic, or neurological disorders capable ofsignificantly altering the absorption, metabolism, or elimination of drugs;constituting a risk when taking the study intervention or interfering with theinterpretation of data

• Obstructive pulmonary disease (pre-bronchodilator Forced Expiratory Volume (FEV1) /FVC <0.7) as confirmed by central reader

• Significant emphysema on screening or historical HRCT (extent of emphysema exceedsextent of ILD) as confirmed by central reader

• Confirmed Progressive multifocal leukoencephalopathy (PML) or unexplained new-onsetor deteriorating neurologic signs and symptoms

• Participants with patient health questionnaire (PHQ-9) score ≥10, that in theopinion of a mental healthcare professional pose a serious suicide risk, have or anyhistory of suicidal behavior in the last 6 months and/or any suicidal ideation inthe last 2 months, or who in the investigator's judgment, poses a significantsuicide risk.

• Lymphoma, leukemia, or any malignancy within the past 5 years except for basal cellor squamous epithelial carcinomas of the skin that have been resected with noevidence of metastatic disease for 3 years

• Breast cancer within the past 10 years

• Major surgery (including joint surgery) within 3 months prior to screening orplanned during the duration of the study

• An active infection, or a history of infections