SLE SRI-4 composite response is a composite response of at least a 4 point reduction in SLE Disease Activity Index 2000 (SLEDAI-2K), no British Isles Lupus Assessment Group-2004 (BILAG-2004) worsening, defined as no new A or less than or equal to \<= 1 new B items compared to baseline, no worsening in Physician's Global Assessment (PGA \[greater than {\>} 10 percent {%} increase from baseline\]).

Average mean percent change from baseline in total IgG levels over Weeks 8 , 10 and 12 will be reported.

Outcome of fetus/neonate death or adjudicated severe bleeding up to the first week post birth or platelet count \<30\*10\^9/L will be reported.

ClinESSDAI is a validated tool used in clinical studies to measure the systemic disease activity in participants with SjD. The ClinESSDAI includes 11 domains divided into 3-4 activity levels, where zero represents no activity and low, medium, and high scores can vary in numerical value depending on the domain being measured. A higher score represents worse disease symptoms.

Percentage of pregnancies that did not result in fetal loss, IUT, hydrops fetalis, or neonatal death (during the neonatal period) will be reported. Hydrops fetalis is defined as the presence of greater than or equal to(\>=)2 abnormal fluid collections in the fetus or neonate, such as ascites, pleural effusions, pericardial effusion, and generalized skin edema (skin thickness greater (\>)5 millimeter \[mm\]). PMA is the time elapsed between the first day of the last menstrual period and birth (gestational age) plus the time elapsed after birth (chronological age).

Average change from baseline over multiple timepoints (Weeks 22, 23, and 24) was reported in this outcome measure. The MG-ADL provided a rapid assessment of the participant's MG symptom severity of eight functions (talking, chewing, swallowing, breathing, impairment of ability to brush teeth or comb hair, impairment of ability to arise from a chair, double vision, eyelid droop) rated on a 4-point scale ranging from 0 (normal) to 3 (severe). MG-ADL total score was sum of 8 individual items, which ranging from 0 to 24. A higher score indicated greater symptom severity. Baseline was defined as the average of the screening and Day 1 total scores.

Change from baseline in DAS28-CRP at Week 12 were reported. The DAS28 is a composite index used to assess rheumatoid arthritis disease activity, calculated based on the tender joint count (out of 28 evaluated joints), swollen joint count (out of 28 evaluated joints), Patient's Global Assessment of Disease Activity, and C-reactive protein (CRP; in milligrams per liter \[mg/L\]). The set of 28 joint count was based on evaluation of the shoulder, elbow, wrist, metacarpophalangeal (MCP) MCP1 to MCP5, proximal interphalangeal (PIP) PIP1 to PIP5 joints of both the upper right extremity and the upper left extremity as well as the knee joints of lower right and lower left extremities. Score on the DAS28 ranged from 0 to 10, where higher scores indicated more disease activity. Negative changes from baseline indicated improvement of arthritis.

Stage B time to first occurrence of a relapse event will be reported.

Change from baseline in total serum IgG levels were reported.

Number of participants with infectious AEs will be reported. An AE is any untoward medical occurrence in a participant participating in a clinical study that does not necessarily have a causal relationship with the pharmaceutical/biological agent under study.

Number of participants with SAEs will be reported. A SAE is any AE that results in: death, persistent or significant disability/incapacity, requires inpatient hospitalization or prolongation of existing hospitalization, is life-threatening experience, is a congenital anomaly/birth defect, is suspected transmission of any infectious agent via a medicinal product, is medically important to prevent one of the outcomes listed above.

Number of participants with AESIs will be reported. Treatment-emergent AEs associated with the following situations are considered an AESI: a) infections that are severe or require intravenous (IV) anti-infective or operative/invasive intervention; b) hypoalbuminemia with albumin less than (\<)20 grams per liter (g/L) \[\<\] 2.0 grams per deciliter \[g/dL\]) c) opportunistic infections and d) Serious and non-serious deep-vein thrombosis (DVT) and/or pulmonary embolism (PE). Any AE occurring at or after the initial administration of study intervention through end of study is treatment emergent.

Number of participants with abnormalities in clinical laboratory tests (including chemistry, hematology, coagulation, and urinalysis) will be reported.

Number of participants with abnormalities in vital signs including sitting pulse/heart rate, sitting systolic and diastolic blood pressure, and oral temperature (degrees Celsius) will be reported.

Number of participants with abnormalities in physical examinations including height, weight, assessments of the skin, head, eyes, ears, nose, throat, neck, thyroid, lungs, heart, abdomen, lymph nodes and extremities will be reported.

Serum samples will be analyzed to determine concentrations of nipocalimab using a validated, specific, and sensitive immunoassay method.

CL is defined as the volume of serum from which nipocalimab is completely removed per unit time.

V is defined as the representation of nipocalimab's propensity to either remain in the serum or redistribute to other tissue compartments.

t1/2 is defined as the time it takes for nipocalimab's active substance in the body to reduce by half.

Cpeak,ss is defined as the peak serum concentration of nipocalimab at steady state.

Ctrough,ss will be reported. It is defined as the observed serum concentration of nipocalimab just prior to the beginning of a dosing interval at steady state.

AUCss is defined as the area under the curve for nipocalimab at steady state.

Percentage of participants who achieve at least minimal improvement (\>=20) in IMACS TIS at Week 52 and on \<=5 mg/day of oral prednisone (or equivalent) from Week 44 through Week 52 will be reported. International Myositis Assessment and Clinical Studies Total Improvement Score (IMACS TIS) is a standardized clinical response criteria to assess minimal, moderate and major clinical improvement in adult participants with idiopathic inflammatory myopathies (IIM). Minimal improvement is defined as IMACS TIS greater than or equal to (\>=) 20 in participants with IIM. The criteria use the 6 IMACS core set measures: physicians' global activity, patient global activity (PtGA), manual muscle testing (MMT)-8, muscle enzymes, myositis disease activity assessment tool (MDAAT), and health assessment questionnaire-disability index (HAQ-DI). The absolute percentage change in each measure with varying weights is combined to obtain a TIS on a scale of 0 to 100. Higher score indicates greater improvement.

The clinESSDAI is a validated tool used in clinical studies to measure the systemic disease activity in participants with primary Sjogren's syndrome. The clinESSDAI includes 11 domains divided into 3-4 activity levels, where zero represents no activity and low, medium, and high scores can vary in numerical value depending on the domain.

SLE SRI-4 composite response is a composite of at least 4-point improvement in SLE Disease Activity Index 2000(SLEDAI-2K), no worsening in British Isles Lupus Assessment Group (BILAG), no worsening in Physician's Global Assessment of Disease Activity score (PGA) and not meeting study treatment failure criteria.

The concentration of nipocalimab in breast milk over a 7-day sampling period (Day 1 up to Day 8) will be reported.

Area under the curve for breast milk concentration vs time curve from time 0 to 168 hours post-dose will be reported.

Percentage of participants with a positive anti-TT IgG response at 4 weeks post-vaccination will be reported. It is defined as pre-vaccination anti-TT IgG antibody titers are less than (\<) 0.16 international units per milliliter (IU/mL) and post-vaccination anti-TT IgG titers are greater than or equal to (\>=) 0.16 IU/mL, or pre-vaccination anti-TT IgG are \>= 0.16 IU/mL and there is at least a 2-fold increase in post-vaccination anti-TT IgG titers.

AUC(0-last) is defined as area under the serum concentration versus time curve from time 0 to time of the last measurable concentration of nipocalimab.

AUC (0-Infinity) is defined as area under the analyte concentration versus time curve from time zero to infinite time of nipocalimab.

Clast is defined as last measurable serum concentration of nipocalimab.

Cmax is defined as maximum observed serum concentration of nipocalimab.

Tlast is defined as time of last measurable serum concentration of nipocalimab.

Tmax is defined as time to reach the maximum observed serum concentration of nipocalimab.

T1/2 is defined as apparent elimination half-life associated with the terminal slope of the semilogarithmic drug concentration-time curve of nipocalimab.

CL is defined as total systemic clearance of nipocalimab after intravenous (IV) administration.

Vz is defined as volume of distribution based on terminal phase after IV administration of nipocalimab.

Serum etanercept concentration will be reported.

AUCR is defined as the ratio of area under the concentration-time curve.

AUC (0-last) is defined as area under the concentration-time curve of etanercept from time zero to time of last observed quantifiable concentration.

AUC (0-Infinity) is defined as area under the concentration-time curve of etanercept from time zero to infinite time, calculated as the sum of AUC (0-last) and C(last)/lambda(z) where AUC (0-last) is area under the concentration-time curve of etanercept from time zero to time of last observed quantifiable concentration and C(last) is the last observed quantifiable concentration, and lambda(z) is apparent terminal elimination rate constant.

Cmax is defined as maximum observed concentration of etanercept.

CmaxR is defined as ratio of maximum observed concentration of etanercept.

Tlast is defined as time to reach the last observed measurable analyte concentration of etanercept.

Tmax is defined as time to reach the maximum observed concentration of etanercept.

t1/2 is defined as elimination half-life associated with the terminal slope lambda(z) of the semilogarithmic drug concentration-time curve, calculated as 0.693/ lambda(z).

CL/F is total apparent clearance of etanercept following subcutaneous (SC) administration, calculated as dose/AUC (0-infinity).

Vdz/F is defined as apparent volume of distribution based on the terminal phase after an SC dose, calculated as dose/lambda(z)\*AUC(0-infinity).

Change from baseline in total serum Ig levels (serum IgG and IgG subtypes) through Day 50 will be reported.

An AE is any untoward medical occurrence in a participant participating in a clinical study that does not necessarily have a causal relationship with the pharmaceutical/biological agent under study.

A SAE is any untoward medical occurrence that at any dose: results in death; is life-threatening; requires inpatient hospitalization or prolongation of existing hospitalization; results in persistent or significant disability/incapacity; is a congenital anomaly/birth defect; is a suspected transmission of any infectious agent via a medicinal product; is medically important.

Percentage of participants with reasonably related AEs will be reported. Reasonably related AE is an AE that has a casual relationship with the pharmaceutical/biological agent under study.

Percentage of participants with AEs leading to discontinuation of study intervention will be reported. The participants were discontinued from the study by the investigator if the safety reasons or tolerability reasons such as an AE, it is in the best interest of the participant to discontinue study intervention.

Percentage of participants with AESIs will be reported. Treatment-emergent AEs associated with the following situations are considered as AESI; a) severe or medically significant or immediately life-threatening infections requiring intravenous (IV) anti-infective or operative/invasive intervention or requiring hospitalization or prolongation of existing hospitalization; b) hypoalbuminemia with albumin less than (\<) 20 grams per liter (g/L). Treatment-emergent AEs are defined as AEs with onset or worsening on or after date of first dose of study treatment.

Number of participants with vital signs abnormalities including body temperature, pulse/heart rate, respiratory rate, blood pressure will be reported.

Number of participants with ECG abnormalities will be reported.

Number of participants with clinical laboratory abnormalities related to hematology, serum chemistry and urinalysis will be reported.

Number of participants with SC injection-site reactions will be reported. An injection-site reaction is any AE at a SC study intervention injection-site.