Study of BOS161721 in Systemic Lupus Erythematosus (SLE)... | NCT03371251

Label	Type	Description	Intervention Names
Phase 1b: BOS161721 20, 60, 120 mg	Experimental	Participants will be randomized to receive a 20 milligram (mg), 60 mg, or 120 mg subcutaneous (SC) dose of BOS161721. Participants may receive a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.	Drug: BOS161721
Phase 1b: Placebo 20, 60, 120 mg	Placebo Comparator	Participants will be randomized to receive a 20 mg, 60 mg, or 120 mg SC dose of placebo. Participants may receive a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.	Drug: Placebo
Phase 2: BOS161721	Experimental	Participants will be randomized to receive a 120 mg SC dose of BOS161721 (as determined from Phase 1b of the study). Participants may receive a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.	Drug: BOS161721
Phase 2: Placebo	Placebo Comparator	Participants will be randomized to receive a 120 mg SC dose of placebo (as determined from Phase 1b of the study). Participants may receive a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.

Name	Type	Description	Arm Group Labels	Other Names
BOS161721	Drug	SC administration	Phase 1b: BOS161721 20, 60, 120 mg Phase 2: BOS161721

Measure	Description	Time Frame
Phase 1b: Number of Participants With Adverse Events (AEs)	The safety, tolerability, and immunogenicity of repeat doses of BOS161721 (20, 60, and 120 mg) administered SC were assessed in adult participants with moderate to severe SLE on limited background standard of care treatment, in order to estimate the optimal dose.	Up to Day 270
Phase 2: Number of Participants With an SLE Responder Index 4 (SRI-4) Response at Day 210	The SRI-4 is a composite index of SLE disease improvement that consists of scores derived from the SLE Disease Activity Index 2000 (SLEDAI-2K), the British Isles Lupus Assessment Group (BILAG) 2004 Index and the Physician's Global Assessment (PGA). Response based on the SRI-4 is defined by: 1) ≥ 4-point reduction in the SLEDAI-2K total score; 2) no new severe disease activity (BILAG A organ score) or more than 1 new moderate organ score (BILAG B) compared with baseline; and 3) no deterioration from baseline in the PGA by ≥ 30 millimeters. The SLEDAI-2K total score falls between 0 and 105, with higher scores representing increased disease activity.The SRI-4 response in participants with moderate to severe SLE is associated with broad improvements in clinical and participant-reported outcomes.	Day 210

Measure	Description	Time Frame
Phase 1b: Maximum Observed Concentration (Cmax)	The PK of BOS161721 was characterized and the optimal dose of BOS161721 was selected based on safety, tolerability, PK and PD data in participants with moderate to severe SLE.	Pre-dose: Days 0, 30, 60, 90, 120, 150, and 180. Post-dose: Days 0, 7, 15, 30, 180, 187, 195, 210, 240, and 270. Post-dose samples were collected at 4, 8, and 24 hours after study drug administration on Days 0, 30, and 180

Eligibility Module

Eligibility Criteria

Inclusion Criteria:

Men and women, ages 18 to 70 years, inclusive
Participants must be mentally capable of giving consent and there must be evidence of a personally signed and dated informed consent document indicating that the participant has been informed of all pertinent aspects of the study
Participants must have Systemic Lupus Erythematosus (SLE) as defined by meeting 4 of the Systemic Lupus International Collaborating Clinics classification criteria for SLE (with at least 1 clinical and 1 immunologic criterion OR Lupus nephritis as the sole clinical criterion in the presence of anti-nuclear antibodies (ANA) or anti-double stranded deoxyribonucleic acid (dsDNA) antibodies), either sequentially or simultaneously
At screening, participants must have at least 1 of the following:
1. Elevated ANA ≥ 1:80 via immunofluorescent assay at the central laboratory
2. Positive anti-dsDNA or anti-Smith (anti-Sm) above the normal level as determined by the central laboratory
At screening, the total Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) score must be ≥ 8, including points from at least 1 of the following clinical components:

a. Arthritis, rash, myositis, mucosal ulcers, pleurisy, pericarditis, and vasculitis Note: Points from lupus headache and organic brain syndrome will also be excluded from qualifying total and clinical SLEDAI-2K scores at screening and Day 0.
A clinical SLEDAI-2K score of ≥ 6 at screening at Day 0. Clinical SLEDAI-2K score is defined as follows:
1. Contains points from arthritis, rash, myositis, mucosal ulcers, pleurisy, pericarditis, or vasculitis
2. Excludes parameters which require central laboratory results: hematuria, pyuria, urinary casts, proteinuria, positive anti-dsDNA, decreased complement, thrombocytopenia, and leukopenia Note: Points from lupus headache and organic brain syndrome will also be excluded from qualifying total and clinical SLEDAI-2K scores at screening and Day 0.
Participants must have at least 1 qualifying A or 2Bs from the following manifestations of SLE, as defined by the British Isles Lupus Assessment Group (BILAG) criteria as modified for use in this study, which must be confirmed by the central data reviewer:
1. BILAG A or B score in the mucocutaneous body system. If a BILAG B score is due to BILAG number 6, mild skin eruption, the CLASI activity score including erythema and scale/hypertrophy must be ≥ 3 excluding points from mucosal ulcers and alopecia.
2. BILAG A or B score in the musculoskeletal body system due to active polyarthritis Note: Hips, shoulders, back, neck, and temporomandibular joints do not count towards the total number of joints with active synovitis.

If only one "B" and no "A" score is present in the mucocutaneous body system or in the musculoskeletal body system due to arthritis, then at least 1 "B" must be present in at least 1 other body system for a total of 2 "B" BILAG body system scores.

- Participants must be currently receiving at least 1 of the following:

Administration for a minimum of 12 weeks, and a stable dose for at least 56 days (8 weeks prior to Day 0) of the following permitted steroid sparing agents: azathioprine (AZA), mycophenolate mofetil or mycophenolic acid, chloroquine, hydroxychloroquine, or methotrexate
If AZA, myocophenolate mofetil, mycophenolic acid, hydroxychloroquine, or MTX were discontinued prior to screening, the washout period must be ≥ 12 weeks.
Corticosteroids (CSs) (prednisone or prednisone-equivalent) at a stable dose of up to 30 mg/day for at least 6 weeks prior to Day 0

i. For participants whose only SLE treatment is CSs, the stable CS dose must be ≥ 10 mg/day for at least 6 weeks prior to Day 0 and no more than 30 mg/day at the time of randomization.

ii. Topical steroids may be used, but the dose must be stable for at least 6 weeks prior to Day 0. PRN topical steroids are not permitted.

Women of childbearing potential (WOCBP):
1. Must have a negative serum pregnancy test at screening. Urine pregnancy test must be negative prior to first dose
2. Must not be breastfeeding
3. Must agree to follow instructions for method(s) of contraception for the duration of treatment with study drug plus 52 weeks
Men who are sexually active with WOCBP must agree to follow instructions for method(s) of contraception for the duration of treatment with study drug plus 52 weeks
Participants must demonstrate willingness and ability to comply with the scheduled study visits, treatment plans, laboratory tests, and other procedures

Exclusion Criteria:

Participants presenting with any of the following will not be included in this study:

Drug-induced SLE, rather than "idiopathic" SLE
Other systemic autoimmune disease (eg, erosive arthritis, rheumatoid arthritis [RA], multiple sclerosis [MS], systemic sclerosis, or vasculitis not related to SLE). RA-Lupus overlap (Rupus), and secondary Sjogren syndrome are allowed.
Any major surgery within 6 weeks of study drug administration (Day 0) or any elective surgery planned during the course of the study
Any history or risk for tuberculosis (TB), specifically those with:
1. Current clinical, radiographic, or laboratory evidence of active TB
2. History of active TB
3. Latent TB defined as positive QuantiFERON-TB Gold In Tube or other diagnostic test in the absence of clinical manifestations. Latent TB is not excluded if the participant has documented completion of adequate course of prophylactic treatment with regimen recommended by local health authority guideline, or the participant has started treatment with isoniazid, or other regimen recommended by local health authority guidelines for at least 1 month before Day 0 and continues to receive the prophylactic treatment during study until the treatment course is completed
Active or unstable lupus neuropsychiatric manifestations, including but not limited to any condition defined by BILAG A criteria, with the exception of mononeuritis multiplex and polyneuropathy, which are allowed
Severe proliferative lupus nephritis (World Health Organization Class III, IV), which requires or may require induction treatment with cytotoxic agents or high dose CSs
Concomitant illness that, in the opinion of the investigator or the Sponsor or their designee, is likely to require additional systemic glucocorticosteroid therapy during the study, (eg, asthma), is exclusionary. However, treatment for asthma with inhalational CSs therapy is allowed.
Use or planned use of concomitant medication outside of standard of baseline treatment for SLE from Day -1 or for any time during the study
Active and clinically significant infection (bacterial, fungal, viral, or other) within 60 days prior to first dose of study drug. Clinically significant is defined as requiring systemic parenteral antibiotics or hospitalization
A history of opportunistic infection, or a history of recurrent or severe disseminated herpes zoster or disseminated herpes simplex within the last 3 years
Chronic viral hepatitis B (HBV) and hepatitis C (HCV), unless participant received curative treatment for HCV and has a documented negative viral load, known human immunodeficiency virus (HIV), or acquired immunodeficiency syndrome (AIDS)-related illness
Cryptosporidium in the stool sample at screening
White blood cells < 1,200/millimeters cubed (mm^3) (1.2 × 10^9/Liter [L]) at screening
Absolute neutrophil count < 500/mm^3 at screening
CD4+ count < 150/microliter (µL) at screening
Platelets < 50,000/mm^3 (50 × 10^9/L) or < 35,000/mm^3 (35 × 10^9/L) if related to SLE, at screening
Hemoglobin < 8 grams per deciliter (g/dL) or < 7 g/dL at screening if related to SLE
Proteinuria > 3.0 g/day (3000 milligrams per day [mg/day]) at screening or equivalent level of proteinuria as assessed by protein/creatinine ratio (3 mg/mg or 339 milligrams per millimole [mg/mmol])
Serum creatinine > 2.0 mg/dL at screening or creatinine clearance < 40 milliliters per minute (mL/minute) based on Cockcroft-Gault calculation
Serum alanine aminotransferase and/or serum aspartate aminotransferase > 2 × the upper limit of normal (ULN) at screening, unless explicitly related to lupus based on the investigator's judgment
Creatinine kinase > 3.0 × ULN at screening unless related to lupus myositis
Total bilirubin > 1.5 × ULN at screening (unless related to Gilbert's syndrome)
Any other laboratory test results that, in the opinion of the Investigator or the Sponsor or Sponsor's designee, might place a participant at unacceptable risk for participating in this study
History of allergic or anaphylactic reaction to any therapeutic or diagnostic monoclonal antibodies (mAb) (eg, IgG protein) or molecules made of components of mAbs
History substance and/or alcohol abuse, or dependence within the past 1 year, at the investigator's judgment
History of cancer within the last 5 years (except for cutaneous basal cell or squamous cell cancer, or cervical cancer in situ resolved by excision)
Any other severe acute or chronic medical or psychiatric condition, including recent (within the past year) medical conditions (eg, cardiovascular conditions, respiratory illnesses) that may increase the risk associated with study participation or investigational product administration or may interfere with the interpretation of study results and, in the judgment of the investigator, Sponsor, or Sponsor's designee, would make the participant inappropriate for entry into this study
Investigational site staff members directly involved in the conduct of the trial and their family members, site staff members otherwise supervised by the investigator, or participants who are employees of the sponsor or directly involved in the conduct of the trial
Currently participating in, or who have participated in other interventional (drug or device) clinical study within 30 days or 5 half-lives of baseline, whichever is longer
Recent (within the past 12 months) or active suicidal ideation or behavior based on participant responding "yes" to question 3, 4, or 5 on the Columbia Suicide severity Rating Scale
Current or pending incarceration
Current or pending compulsory detainment for treatment of either a psychiatric or physical (eg, infectious disease) illness
Currently taking a total daily dose of > 30 mg morphine or morphine equivalent
Body mass index (BMI) ≥ 40.0

Facility	Status	City	State	ZIP	Country	Contacts
Pinnacle Research Group		Anniston	Alabama	36207	United States
TriWest Research Associates

PubMed Identifier	Type	Citation	Retractions
40465397	Derived	Ahmad SB, Jefferson JA. Targeting B Cells and Plasma Cells in Glomerular Disease. J Am Soc Nephrol. 2025 Jun 4;36(9):1844-1857. doi: 10.1681/ASN.0000000772.

ID	Title	Description
FG000	Phase 1b: Placebo	Participants were randomized to receive subcutaneous (SC) dose of placebo. Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits at Days 210, 240, and 270.
FG001	Phase 1b: Cohort 1: BOS161721 20 mg

Type	Includes Protocol	Includes SAP	Includes ICF	Document Label	Document Date	Document Uploaded Date	Document File Name
Prot	Yes	No	No	Study Protocol	Apr 30, 2020	Nov 11, 2021

Type

Title

Description

Population Description

Reporting Status

Anticipated Posting Date

Parameter Type

Dispersion Type

Unit of Measure

Calculate Percentage

Time Frame

Units Analyzed

Denominator Units Selected

Arm/Group Information

Denominators

Classes

Analyses

Primary

Phase 1b: Number of Participants With Adverse Events (AEs)

The safety, tolerability, and immunogenicity of repeat doses of BOS161721 (20, 60, and 120 mg) administered SC were assessed in adult participants with moderate to severe SLE on limited background standard of care treatment, in order to estimate the optimal dose.

Safety Analysis Set (SS): Defined as all participants who received at least 1 dose (partial or complete) of study treatment and had at least one evaluable post-baseline safety evaluation.

Posted

Count of Participants

Participants

Up to Day 270

ID	Title	Description
OG000	Phase 1b: Placebo	Participants were randomized to receive a subcutaneous (SC) dose of placebo. Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits at Days 210, 240, and 270.
OG001	Phase 1b: Cohort 1: BOS161721 20 mg	Participants were randomized to receive a 20 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG002	Phase 1b: Cohort 2: BOS161721 60 mg	Participants were randomized to receive a 60 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270
OG003	Phase 1b: Cohort 3: BOS161721 120 mg	Participants were randomized to receive a 120 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270

Units	Counts
Participants	OG0007 OG0015 OG0029 OG003

Title

Denominators

Categories

Any Treatment-Emergent Adverse Events (TEAE)

Title	Measurements
	OG0004 OG0012 OG0027 OG003

Primary

Phase 2: Number of Participants With an SLE Responder Index 4 (SRI-4) Response at Day 210

The SRI-4 is a composite index of SLE disease improvement that consists of scores derived from the SLE Disease Activity Index 2000 (SLEDAI-2K), the British Isles Lupus Assessment Group (BILAG) 2004 Index and the Physician's Global Assessment (PGA). Response based on the SRI-4 is defined by: 1) ≥ 4-point reduction in the SLEDAI-2K total score; 2) no new severe disease activity (BILAG A organ score) or more than 1 new moderate organ score (BILAG B) compared with baseline; and 3) no deterioration from baseline in the PGA by ≥ 30 millimeters. The SLEDAI-2K total score falls between 0 and 105, with higher scores representing increased disease activity.The SRI-4 response in participants with moderate to severe SLE is associated with broad improvements in clinical and participant-reported outcomes.

Full Analysis Set: Defined as all participants who received at least 1 dose (partial or complete) of study treatment and had at least 1 evaluable post-baseline efficacy evaluation.

Posted

Count of Participants

Participants

Day 210

ID	Title	Description
OG000	Phase 2: Placebo	Participants were randomized to receive a SC dose of placebo (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001	Phase 2: BOS161721 120 mg

Secondary

Phase 1b: Maximum Observed Concentration (Cmax)

The PK of BOS161721 was characterized and the optimal dose of BOS161721 was selected based on safety, tolerability, PK and PD data in participants with moderate to severe SLE.

The PK population is defined as all participants who received at least 1 dose (partial or complete) of study treatment and had sufficient concentration data for the calculation of PK parameters. Here, number analyzed in each row signifies only the participants with available data for each dose.

Posted

Geometric Mean

Geometric Coefficient of Variation

ng/mL

Pre-dose: Days 0, 30, 60, 90, 120, 150, and 180. Post-dose: Days 0, 7, 15, 30, 180, 187, 195, 210, 240, and 270. Post-dose samples were collected at 4, 8, and 24 hours after study drug administration on Days 0, 30, and 180

ID	Title	Description
OG000	Phase 1b: Cohort 1: BOS161721 20 mg	Participants were randomized to receive a 20 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001	Phase 1b: Cohort 2: BOS161721 60 mg	Participants were randomized to receive a 60 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270

Secondary

Phase 1b: First Time to Maximum Concentration (Tmax)

The PK of BOS161721 was characterized and the optimal dose of BOS161721 was selected based on safety, tolerability, PK and PD data in participants with moderate to severe SLE.

Posted

Median

Full Range

Day

ID	Title	Description
OG000	Phase 1b: Cohort 1: BOS161721 20 mg	Participants were randomized to receive a 20 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001	Phase 1b: Cohort 2: BOS161721 60 mg	Participants were randomized to receive a 60 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270

Secondary

Phase 1b: The Area Under the Plasma Concentration Versus Time Curve, From Time 0 to the Last Quantifiable Concentration (AUClast)

The PK of BOS161721 was characterized and the optimal dose of BOS161721 was selected based on safety, tolerability, PK and PD data in participants with moderate to severe SLE.

Posted

Geometric Mean

Geometric Coefficient of Variation

day*ng/mL

ID	Title	Description
OG000	Phase 1b: Cohort 1: BOS161721 20 mg	Participants were randomized to receive a 20 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001	Phase 1b: Cohort 2: BOS161721 60 mg	Participants were randomized to receive a 60 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270

Secondary

Phase 1b: Terminal Elimination Half-life (t1/2)

The PK of BOS161721 was characterized and the optimal dose of BOS161721 was selected based on safety, tolerability, PK and PD data in participants with moderate to severe SLE.

The PK population is defined as all participants who received at least 1 dose (partial or complete) of study treatment and had sufficient concentration data for the calculation of PK parameters. Here, overall number of participants analyzed signifies only the participants with available data for the outcome measure.

Posted

Geometric Mean

Geometric Coefficient of Variation

Day

ID	Title	Description
OG000	Phase 1b: Cohort 1: BOS161721 20 mg	Participants were randomized to receive a 20 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001	Phase 1b: Cohort 2: BOS161721 60 mg	Participants were randomized to receive a 60 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270

Secondary

Phase 1b: Apparent Plasma Clearance After Extravascular Administration (CL/F)

The PK of BOS161721 was characterized and the optimal dose of BOS161721 was selected based on safety, tolerability, PK and PD data in participants with moderate to severe SLE.

The PK population is defined as all participants who received at least 1 dose (partial or complete) of study treatment and had sufficient concentration data for the calculation of PK parameters. Here, overall number of participants analyzed signifies only the participants with available data for the outcome measure.

Posted

Geometric Mean

Geometric Coefficient of Variation

Liter/day

ID	Title	Description
OG000	Phase 1b: Cohort 1: BOS161721 20 mg	Participants were randomized to receive a 20 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001	Phase 1b: Cohort 2: BOS161721 60 mg	Participants were randomized to receive a 60 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270

Secondary

Phase 1b: Apparent Volume of Distribution After Extravascular Administration (Vz/F)

The PK of BOS161721 was characterized and the optimal dose of BOS161721 was selected based on safety, tolerability, PK and PD data in participants with moderate to severe SLE.

The PK population is defined as all participants who received at least 1 dose (partial or complete) of study treatment and had sufficient concentration data for the calculation of PK parameters. Here, overall number of participants analyzed signifies only the participants with available data for the outcome measure.

Posted

Geometric Mean

Geometric Coefficient of Variation

Liter

ID	Title	Description
OG000	Phase 1b: Cohort 1: BOS161721 20 mg	Participants were randomized to receive a 20 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001	Phase 1b: Cohort 2: BOS161721 60 mg	Participants were randomized to receive a 60 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270

Secondary

Phase 1b: Mean Change From Baseline in Phosphorylated Signal Transducer and Activator of Transcription 3 (pSTAT3)

The optimal dose of BOS161721 was selected based on safety, tolerability, PK and pharmacodynamic (PD) data in participants with moderate to severe SLE.

Posted

Mean

Standard Deviation

Percentage

Baseline (Day 0); Days 30, 44, 60, and 90 (pre-dose [trough] samples only)

ID	Title	Description
OG000	Phase 1b: Placebo	Participants were randomized to receive a subcutaneous (SC) dose of placebo. Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits at Days 210, 240, and 270.
OG001	Phase 1b: Cohort 1: BOS161721 20 mg	Participants were randomized to receive a 20 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG002	Phase 1b: Cohort 2: BOS161721 60 mg

Secondary

Phase 1b: Mean Change From Baseline in Complement 3 (C3) and Complement (C4) Levels

The optimal dose of BOS161721 was selected based on safety, tolerability, PK and PD data in participants with moderate to severe SLE.

Posted

Mean

Standard Deviation

gram/Litre

Baseline (Day 0); Day 210

ID	Title	Description
OG000	Phase 1b: Placebo	Participants were randomized to receive a subcutaneous (SC) dose of placebo. Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits at Days 210, 240, and 270.
OG001	Phase 1b: Cohort 1: BOS161721 20 mg	Participants were randomized to receive a 20 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG002	Phase 1b: Cohort 2: BOS161721 60 mg

Secondary

Phase 1b: Mean Change From Baseline in Leukocyte Immunophenotype

The optimal dose of BOS161721 was selected based on safety, tolerability, PK and PD data in participants with moderate to severe SLE.

Full Analysis Set: Defined as all participants who received at least 1 dose (partial or complete) of study treatment and had at least 1 evaluable post baseline efficacy evaluation.

Posted

Mean

Standard Deviation

Change in percentage of cells

Baseline (Day 0); Day 180

ID	Title	Description
OG000	Phase 1b: Placebo	Participants were randomized to receive a subcutaneous (SC) dose of placebo. Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits at Days 210, 240, and 270.
OG001	Phase 1b: Cohort 1: BOS161721 20 mg	Participants were randomized to receive a 20 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG002	Phase 1b: Cohort 2: BOS161721 60 mg	Participants were randomized to receive a 60 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270

Secondary

Phase 1b: Mean Change From Baseline in Anti-double-stranded DNA (dsDNA) Autoantibodies at Each Visit

The optimal dose of BOS161721 was selected based on safety, tolerability, PK and PD data in participants with moderate to severe SLE..

Posted

Mean

Standard Deviation

International units per millilitre

Baseline (Day 0); Days 30, 60, 90, 120, 150, 180, 210, 240, and 270

ID	Title	Description
OG000	Phase 1b: Placebo	Participants were randomized to receive a subcutaneous (SC) dose of placebo. Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits at Days 210, 240, and 270.
OG001	Phase 1b: Cohort 1: BOS161721 20 mg	Participants were randomized to receive a 20 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG002	Phase 1b: Cohort 2: BOS161721 60 mg

Secondary

Phase 1b: Mean Change From Baseline in Anti-Sjögren's Syndrome A and B (SSA, SSB)

The optimal dose of BOS161721 was selected based on safety, tolerability, PK and PD data in subjects with moderate to severe SLE.

Full Analysis Set: Defined as all participants who received at least 1 dose (partial or complete) of study treatment and have at least 1 evaluable post baseline efficacy evaluation.

Posted

Mean

Standard Deviation

U/mL

Baseline (Day 0); Day 180

ID	Title	Description
OG000	Phase 1b: Placebo	Participants were randomized to receive a subcutaneous (SC) dose of placebo. Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits at Days 210, 240, and 270.
OG001	Phase 1b: Cohort 1: BOS161721 20 mg	Participants were randomized to receive a 20 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG002	Phase 1b: Cohort 2: BOS161721 60 mg	Participants were randomized to receive a 60 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270

Secondary

Phase 1b: Mean Change From Baseline in Anti-Smith Antibody (Sm)

The optimal dose of BOS161721 was selected based on safety, tolerability, PK and PD data in subjects with moderate to severe SLE.

Full Analysis Set: Defined as all participants who received at least 1 dose (partial or complete) of study treatment and have at least 1 evaluable post baseline efficacy evaluation.

Posted

Mean

Standard Deviation

U/mL

Baseline (Day 0); Day 180

ID	Title	Description
OG000	Phase 1b: Placebo	Participants were randomized to receive a subcutaneous (SC) dose of placebo. Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits at Days 210, 240, and 270.
OG001	Phase 1b: Cohort 1: BOS161721 20 mg	Participants were randomized to receive a 20 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG002	Phase 1b: Cohort 2: BOS161721 60 mg	Participants were randomized to receive a 60 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270

Secondary

Phase 1b: Mean Change From Baseline in Antiphospholipid (APL) Autoantibodies (Beta 2 Glycoprotein, Cardiolipin IgG)

The optimal dose of BOS161721 was selected based on safety, tolerability, PK and PD data in participants with moderate to severe SLE.

Full Analysis Set: Defined as all participants who received at least 1 dose (partial or complete) of study treatment and have at least 1 evaluable post baseline efficacy evaluation.

Posted

Mean

Standard Deviation

U/mL

Baseline (Day 0); Day 180

ID	Title	Description
OG000	Phase 1b: Placebo	Participants were randomized to receive a subcutaneous (SC) dose of placebo. Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits at Days 210, 240, and 270.
OG001	Phase 1b: Cohort 1: BOS161721 20 mg	Participants were randomized to receive a 20 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG002	Phase 1b: Cohort 2: BOS161721 60 mg	Participants were randomized to receive a 60 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270

Secondary

Phase 1b: Mean Change From Baseline in Abrogation of IL-21 Gene Signature

The optimal dose of BOS161721 was selected based on safety, tolerability, PK and PD data in participants with moderate to severe SLE.

Full Analysis Set: Defined as all participants who received at least 1 dose (partial or complete) of study treatment and have at least 1 evaluable post baseline efficacy evaluation. Data were not collected for this outcome measure.

Posted

Baseline (Day 0); Days 15, 90, 180, and 270

ID	Title	Description
OG000	Phase 1b: Placebo	Participants were randomized to receive a subcutaneous (SC) dose of placebo. Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits at Days 210, 240, and 270.
OG001	Phase 1b: Cohort 1: BOS161721 20 mg	Participants were randomized to receive a 20 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG002	Phase 1b: Cohort 2: BOS161721 60 mg	Participants were randomized to receive a 60 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270

Secondary

Phase 2: Number of Participants With an SRI-4, SRI-5, and SRI-6 Response at Each Visit

The SRI-4 is a composite index of SLE disease improvement that consists of scores derived from the SLE Disease Activity Index 2000 (SLEDAI-2K) and the British Isles Lupus Assessment Group (BILAG) 2004 Index. Response based on the SRI-4 is defined by: 1) ≥ 4-point reduction in the SLEDAI-2K global score; 2) no new severe disease activity (BILAG A organ score) or more than 1 new moderate organ score (BILAG B); and 3) no deterioration from baseline in the Physician's Global Assessment (PGA) by ≥ 30 millimeters. The SRI-4 response in participants with moderate to severe SLE is associated with broad improvements in clinical and participant-reported outcomes. SRI-5 and SRI-6 are composite indices of SLE disease improvement that consist of scores derived from the SLEDAI-2K and the BILAG 2004 Index. The SRI-5 and SRI-6 are computed with a minimal five-point or six-point improvement in SLEDAI-2K being required, respectively.

Posted

Count of Participants

Participants

Days 30, 60, 90, 120, 150, 180, 210, 240, and 270

ID	Title	Description
OG000	Phase 2: Placebo	Participants were randomized to receive a SC dose of placebo (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.

Secondary

Phase 2: Number of Participants With a Sustained Reduction From Baseline of Oral Corticosteroid (CS) (≤ 7.5 mg/Day and < Day 0 Dose) Between Day 150 and Day 210

Effect of BOS161721 compared with placebo for response on clinical indicators of SLE activity was assessed in adult participants with moderate to severe SLE on limited background standard of care treatment.

Full Analysis Set: Defined as all participants who received at least 1 dose (partial or complete) of study treatment and had at least 1 evaluable post baseline efficacy evaluation. Here, overall number of participants analyzed signifies only the number of participants taking oral corticosteroids at baseline.

Posted

Count of Participants

Participants

Day 150 to Day 210

ID	Title	Description
OG000	Phase 2: Placebo	Participants were randomized to receive a SC dose of placebo (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001	Phase 2: BOS161721 120 mg	Participants were randomized to receive a 120 mg SC dose of BOS161721 (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.

Secondary

Phase 2: Number of Participants With New or Recurrent BILAG Flares (≥ 1 Qualifying BILAG A or > 1 Qualifying BILAG B) Through Day 210

The BILAG-2004 index is an organ-specific 97-question assessment based on the principle of the doctor's intent to treat. Only clinical features attributable to SLE disease activity were recorded and based on the participant's condition in the last 4 weeks compared with the previous 4 weeks. It was scored as not present (0), improved (1), the same (2), worse (3), or new (4). Disease activity was graded separately for 9 body systems to 5 different grades (A to E) as follows: A is very active disease, B is moderate activity, C is mild stable disease, D is inactive now but previously active, and E indicates the organ was never involved. A shift from BILAG-2004 Grade A or B to a lower grade indicates a clinically relevant change in disease activity as the BILAG-2004 grades mirror the decision points for treatment interventions.

Full Analysis Set: Defined as all participants who received at least 1 dose (partial or complete) of study treatment and had at least 1 evaluable post baseline efficacy evaluation. Here, number analyzed in each row signifies only the number of participants with a post-baseline BILAG assessment at any time (overall assessment) or at the given timepoint.

Posted

Count of Participants

Participants

Days 30, 60, 90, 120, 150, 180, 210

ID	Title	Description
OG000	Phase 2: Placebo	Participants were randomized to receive a SC dose of placebo (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.

Secondary

Phase 2: Number of Participants With Physician's Global Assessment (PGA) Worsening

The PGA is used to assess Investigator's general impression on the patient's overall status of SLE disease activity via visual analogue scale (100 mm) with 0 being "very good, asymptomatic and no limitation of normal activities" with 100 mm being "most severe possible disease ever seen in all SLE patients". PGA worsening is defined as an increase of ≥ 30 mm from baseline.

Full Analysis Set: Defined as all participants who received at least 1 dose (partial or complete) of study treatment and had at least 1 evaluable post baseline efficacy evaluation. Here, number analyzed in each row signifies the number of participants with a post-baseline PGA assessment at any time (overall assessment) or at the given timepoint (by visit assessment).

Posted

Count of Participants

Participants

Days 30, 60, 90, 120, 150, 180, and 210

ID	Title	Description
OG000	Phase 2: Placebo	Participants were randomized to receive a SC dose of placebo (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001	Phase 2: BOS161721 120 mg	Participants were randomized to receive a 120 mg SC dose of BOS161721 (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.

Secondary

Phase 2: Number of Participants With a BILAG-based Composite Lupus Assessment (BICLA) Response at Day 210

The BICLA is a responder index developed to measure response to therapy, and it includes scores from the BILAG, SLEDAI-2K, and Physician's Global Assessment (PGA). BICLA response is defined as: 1) at least 1 gradation of improvement in baseline BILAG 2004 scores in all body systems with moderate disease activity at entry (eg, all B [moderate disease] scores falling to C [mild], or D [no activity]); 2) no new BILAG A or more than 1 new BILAG B scores; 3) no worsening of total SLEDAI-2K score from baseline; 4) ≤ 10% deterioration in PGA score; and 5) no treatment failure. The PGA is measured on a 0 to 100 mm scale with score 0 to be No Disease Activity and score 100 to be the most Severe Disease Activity.

Full Analysis Set: Defined as all participants who received at least 1 dose (partial or complete) of study treatment and had at least 1 evaluable post baseline efficacy evaluation.

Posted

Count of Participants

Participants

Day 210

ID	Title	Description
OG000	Phase 2: Placebo	Participants were randomized to receive a SC dose of placebo (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001	Phase 2: BOS161721 120 mg	Participants were randomized to receive a 120 mg SC dose of BOS161721 (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.

Secondary

Phase 2: Number of Participants With a Cutaneous Lupus Erythematosus Area and Severity Index (CLASI) Response at Day 210

The CLASI is a comprehensive tool for assessment of disease activity (CLASI-A) in cutaneous lupus, shown to be valid, reliable, and sensitive to changes in disease activity. Response is defined as at least 50% improvement from baseline in "A" scores. This assessment was applied to all participants as all were required to have cutaneous disease activity. The total score represents the sum of the individual scores and ranges from 0 to 70. Higher scores are awarded for more severe manifestations.

Full Analysis Set: Defined as all participants who received at least 1 dose (partial or complete) of study treatment and had at least 1 evaluable post baseline efficacy evaluation.

Posted

Count of Participants

Participants

Day 210

ID	Title	Description
OG000	Phase 2: Placebo	Participants were randomized to receive a SC dose of placebo (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001	Phase 2: BOS161721 120 mg	Participants were randomized to receive a 120 mg SC dose of BOS161721 (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.

Secondary

Phase 2: Number of Participants With Medication Failures

Full Analysis Set: Defined as all participants who received at least 1 dose (partial or complete) of study treatment and had at least 1 evaluable post baseline efficacy evaluation. Here, number analyzed in each row signifies the number of participants evaluable at any time (overall assessment) or at the given timepoint (by visit assessment).

Posted

Count of Participants

Participants

Days 30, 60, 90, 120, 150, 180, and 210

ID	Title	Description
OG000	Phase 2: Placebo	Participants were randomized to receive a SC dose of placebo (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001	Phase 2: BOS161721 120 mg	Participants were randomized to receive a 120 mg SC dose of BOS161721 (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.

Secondary

Phase 2: Mean Change From Baseline in CLASI at Day 210

The CLASI is a comprehensive tool for the assessment of disease activity (CLASI-A) and damage (CLASI-B) in cutaneous lupus, shown to be valid, reliable, and sensitive to changes in disease activity. Response is defined as 50% improvement from baseline in "A" or "B" scores. This assessment was applied to all participants as all were required to have cutaneous disease activity. The total score represents the sum of the individual scores and ranges from 0 to 70 (CLASI-A) and 0 to 58 (CLASI-B). Higher scores are awarded for more severe manifestations. Change from baseline was calculated as the post-baseline value minus the baseline value.

Full Analysis Set: Defined as all participants who received at least 1 dose (partial or complete) of study treatment and had at least 1 evaluable post baseline efficacy evaluation.

Posted

Mean

Standard Deviation

score on a scale

Baseline, Day 210

ID	Title	Description
OG000	Phase 2: Placebo	Participants were randomized to receive a SC dose of placebo (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001	Phase 2: BOS161721 120 mg	Participants were randomized to receive a 120 mg SC dose of BOS161721 (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.

Secondary

Phase 2: Mean Change From Baseline in PGA

Full Analysis Set: Defined as all participants who received at least 1 dose (partial or complete) of study treatment and had at least 1 evaluable post baseline efficacy evaluation.

Posted

Mean

Standard Deviation

score on a scale

Baseline, Day 210

ID	Title	Description
OG000	Phase 2: Placebo	Participants were randomized to receive a SC dose of placebo (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001	Phase 2: BOS161721 120 mg	Participants were randomized to receive a 120 mg SC dose of BOS161721 (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.

Secondary

Phase 2: Mean Change From Baseline in the Total Number of Swollen Joints, Tender Joints, and Active Joints (Swelling and Tenderness in the Same Joint) in the American College of Rheumatology-28 (ACR-28) Joint Count

The ACR-28 joint count evaluated the number of tender and swollen joints in the shoulder, elbow, wrist, hand, and knee joints. Joints of the feet were excluded. Change from baseline was calculated as the post-baseline value minus the baseline value.

Full Analysis Set: Defined as all participants who received at least 1 dose (partial or complete) of study treatment and had at least 1 evaluable post baseline efficacy evaluation.

Posted

Mean

Standard Deviation

Number of swollen/tender/active joints

Baseline, Day 210

ID	Title	Description
OG000	Phase 2: Placebo	Participants were randomized to receive a SC dose of placebo (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001	Phase 2: BOS161721 120 mg	Participants were randomized to receive a 120 mg SC dose of BOS161721 (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.

Secondary

Phase 2: Mean Change From Baseline in SLEDAI-2K at Day 210

The SLEDAI-2K is a validated instrument that measures disease activity in SLE participants at the time of the visit and in the previous 30 days. It is a global index and includes 24 clinical and laboratory variables that are weighted by the type of manifestation, but not by severity. The total score falls between 0 and 105, with higher scores representing increased disease activity. A SLEDAI -2K of 6 or more generally represents moderately to severely active disease.

Change from baseline was calculated as the post-baseline value minus the baseline value.

Full Analysis Set: Defined as all participants who received at least 1 dose (partial or complete) of study treatment and had at least 1 evaluable post baseline efficacy evaluation.

Posted

Mean

Standard Deviation

score on a scale

Baseline, Day 210

ID	Title	Description
OG000	Phase 2: Placebo	Participants were randomized to receive a SC dose of placebo (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001	Phase 2: BOS161721 120 mg	Participants were randomized to receive a 120 mg SC dose of BOS161721 (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.

Secondary

Phase 2: Mean Change From Baseline in Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) Damage Index

The SLICC/ACR damage index is a validated instrument to assess damage, defined as irreversible impairment, continuously persistent for 6 months (ascertained by clinical assessment), occurring since the onset of lupus, and it is based on a weighted scoring system. This index records damage occurring in participants with SLE regardless of cause, with demonstrated content, face, criterion, and discriminant validity. A score of 0=no damage. Total maximum score is 47 and increasing score indicates increasing disease severity.

Full Analysis Set: Defined as all participants who received at least 1 dose (partial or complete) of study treatment and had at least 1 evaluable post baseline efficacy evaluation. Here, overall number of participants analyzed signifies only the participants with available data for the outcome measure.

Posted

Mean

Standard Deviation

score on a scale

Baseline; Day 180

ID	Title	Description
OG000	Phase 2: Placebo	Participants were randomized to receive a SC dose of placebo (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001	Phase 2: BOS161721 120 mg	Participants were randomized to receive a 120 mg SC dose of BOS161721 (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.

Secondary

Phase 2: Time to Medication Failure

Participants who received prohibited medications or undergo unallowable corticosteroid (CS) usage were considered "medication failures".

Full Analysis Set: Defined as all participants who received at least 1 dose (partial or complete) of study treatment and had at least 1 evaluable post baseline efficacy evaluation.

Posted

Median

90% Confidence Interval

Days

Up to Day 270

ID	Title	Description
OG000	Phase 2: Placebo	Participants were randomized to receive a SC dose of placebo (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001	Phase 2: BOS161721 120 mg	Participants were randomized to receive a 120 mg SC dose of BOS161721 (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.

Units	Counts
Participants

Secondary

Mean Percent Change in CS Administration From the Baseline Day 0 Dose Through Day 210 in Participants Receiving ≥ 7.5 mg/Day Prednisone Equivalent at Day 0

The percent reduction in CS administration from Day 0 through Day 210 was determined based on the average daily CS usage.

Full Analysis Set: Defined as all participants who received at least 1 dose (partial or complete) of study treatment and had at least 1 evaluable post baseline efficacy evaluation. Participants in the Full Analysis Set who received >= 7.5 mg/day prednisone equivalent at Day 0 were included. Here, overall number of participants analyzed signifies only the participants with available data for the outcome measure.

Posted

Mean

Standard Deviation

Percent Reduction in Dose (mg/day)

Baseline; Day 210

ID	Title	Description
OG000	Phase 2: Placebo	Participants were randomized to receive a SC dose of placebo (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001	Phase 2: BOS161721 120 mg	Participants were randomized to receive a 120 mg SC dose of BOS161721 (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.

Secondary

Phase 2: Duration of Longest SRI-4 Response

The SRI-4 is a composite index of SLE disease improvement that consists of scores derived from SLEDAI-2K, BILAG 2004 Index and PGA. Response based on the SRI-4 is defined by: 1) ≥ 4-point reduction in the SLEDAI-2K total score; 2) no new severe disease activity (BILAG A organ score) or more than 1 new moderate organ score (BILAG B) compare with baseline; and 3) no deterioration from baseline in the PGA by ≥ 30 millimeters. The total SLEDAI-2K score falls between 0 and 105, with higher scores representing increased disease activity. The PGA is used to assess Investigator's general impression on the patient's overall status of SLE disease activity via visual analogue scale (100 mm) with 0 being "very good, asymptomatic and no limitation of normal activities" with 100 mm being "most severe possible disease ever seen in all SLE patients". The SRI-4 response in participants with moderate to severe SLE is associated with broad improvements in clinical and participant-reported outcomes.

Full Analysis Set: Defined as all participants who received at least 1 dose (partial or complete) of study treatment and had at least 1 evaluable post baseline efficacy evaluation.

Posted

Mean

Standard Deviation

Days

Up to Day 270

ID	Title	Description
OG000	Phase 2: Placebo	Participants were randomized to receive a SC dose of placebo (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001

Secondary

Phase 2: Time to First BILAG Flare (≥ 1 New or Recurrent BILAG A or > 1 New or Recurrent BILAG B) Relative to Baseline Through Day 210

Full Analysis Set: Defined as all participants who received at least 1 dose (partial or complete) of study treatment and had at least 1 evaluable post baseline efficacy evaluation.

Posted

Median

90% Confidence Interval

Days

Baseline; Day 210

ID	Title	Description
OG000	Phase 2: Placebo	Participants were randomized to receive a SC dose of placebo (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001	Phase 2: BOS161721 120 mg

Secondary

Phase 2: Number of Participants With AEs

The safety and tolerability of repeat doses of BOS161721 (120 mg) administered SC were assessed in adult participants with moderate to severe SLE on limited background standard of care treatment.

Safety Analysis Set (SS): Defined as all participants who received at least 1 dose (partial or complete) of study treatment and had at least one evaluable post-baseline safety evaluation.

Posted

Count of Participants

Participants

Up to Day 270

ID	Title	Description
OG000	Phase 2: Placebo	Participants were randomized to receive a SC dose of placebo (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
OG001	Phase 2: BOS161721 120 mg	Participants were randomized to receive a 120 mg SC dose of BOS161721 (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.

Units	Counts

Other Adverse Events

Term	Organ System	Source Vocabulary	Assessment Type	Statistical Information
Anaemia	Blood and lymphatic system disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG0030 events0 affected9 at risk EG0042 events2 affected37 at risk EG0050 events0 affected76 at risk
Iron Deficiency Anaemia	Blood and lymphatic system disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Bundle Branch Block Right	Cardiac disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0021 events1 affected9 at risk EG003
Cataract	Eye disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0021 events1 affected9 at risk EG003
Diplopia	Eye disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0021 events1 affected9 at risk EG003
Nausea	Gastrointestinal disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0002 events1 affected7 at risk EG0010 events0 affected5 at risk EG0021 events1 affected9 at risk EG003
Diarrhoea	Gastrointestinal disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0001 events1 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Constipation	Gastrointestinal disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0001 events1 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Vomiting	Gastrointestinal disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0001 events1 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Abdominal Pain	Gastrointestinal disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0021 events1 affected9 at risk EG003
Dental Caries	Gastrointestinal disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Dry Mouth	Gastrointestinal disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Tongue Ulceration	Gastrointestinal disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0021 events1 affected9 at risk EG003
Non-Cardiac Chest Pain	General disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Nasopharyngitis	Infections and infestations	MedDRA Version 23.1	Non-systematic Assessment	EG0001 events1 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Urinary Tract Infection	Infections and infestations	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0013 events1 affected5 at risk EG0020 events0 affected9 at risk EG003
Pharyngitis	Infections and infestations	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0011 events1 affected5 at risk EG0020 events0 affected9 at risk EG003
Upper Respiratory Tract Infection	Infections and infestations	MedDRA Version 23.1	Non-systematic Assessment	EG0001 events1 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Bronchitis	Infections and infestations	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Escherichia Urinary Tract Infection	Infections and infestations	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Cervicitis	Infections and infestations	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Pneumonia	Infections and infestations	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Vulvovaginal Mycotic Infection	Infections and infestations	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0021 events1 affected9 at risk EG003
Diverticulitis	Infections and infestations	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0021 events1 affected9 at risk EG003
Gastroenteritis Viral	Infections and infestations	MedDRA Version 23.1	Non-systematic Assessment	EG0001 events1 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Herpes Zoster	Infections and infestations	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0021 events1 affected9 at risk EG003
Infected Bite	Infections and infestations	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Nasal Abscess	Infections and infestations	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0021 events1 affected9 at risk EG003
Otitis Media Acute	Infections and infestations	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0011 events1 affected5 at risk EG0020 events0 affected9 at risk EG003
Sinusitis	Infections and infestations	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Viral Upper Respiratory Tract Infection	Infections and infestations	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Fall	Injury, poisoning and procedural complications	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Animal Bite	Injury, poisoning and procedural complications	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Ankle Fracture	Injury, poisoning and procedural complications	MedDRA Version 23.1	Non-systematic Assessment	EG0001 events1 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Ligament Sprain	Injury, poisoning and procedural complications	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
White Blood Cells Urine Positive	Investigations	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0022 events1 affected9 at risk EG003
Blood Pressure Increased	Investigations	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0021 events1 affected9 at risk EG003
Weight Increased	Investigations	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0011 events1 affected5 at risk EG0020 events0 affected9 at risk EG003
Type 2 Diabetes Mellitus	Metabolism and nutrition disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Back Pain	Musculoskeletal and connective tissue disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Arthralgia	Musculoskeletal and connective tissue disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0001 events1 affected7 at risk EG0010 events0 affected5 at risk EG0021 events1 affected9 at risk EG003
Bursitis	Musculoskeletal and connective tissue disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Fibromyalgia	Musculoskeletal and connective tissue disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Muscle Spasms	Musculoskeletal and connective tissue disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0001 events1 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Pain In Extremity	Musculoskeletal and connective tissue disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Sjogren's Syndrome	Musculoskeletal and connective tissue disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0011 events1 affected5 at risk EG0020 events0 affected9 at risk EG003
Myalgia	Musculoskeletal and connective tissue disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Headache	Nervous system disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0011 events1 affected5 at risk EG0020 events0 affected9 at risk EG003
Migraine	Nervous system disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0001 events1 affected7 at risk EG0010 events0 affected5 at risk EG0021 events1 affected9 at risk EG003
Cervical Radiculopathy	Nervous system disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0021 events1 affected9 at risk EG003
Confusional State	Psychiatric disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0011 events1 affected5 at risk EG0020 events0 affected9 at risk EG003
Depression	Psychiatric disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0001 events1 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Insomnia	Psychiatric disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0011 events1 affected5 at risk EG0020 events0 affected9 at risk EG003
Menorrhagia	Reproductive system and breast disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Adnexa Uteri Pain	Reproductive system and breast disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Chronic Obstructive Pulmonary Disease	Respiratory, thoracic and mediastinal disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0021 events1 affected9 at risk EG003
Cough	Respiratory, thoracic and mediastinal disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0011 events1 affected5 at risk EG0020 events0 affected9 at risk EG003
Pulmonary Hypertension	Respiratory, thoracic and mediastinal disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0001 events1 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Hypertension	Vascular disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0011 events1 affected5 at risk EG0021 events1 affected9 at risk EG003
Deep Vein Thrombosis	Vascular disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0021 events1 affected9 at risk EG003

ID	Term
D003240	Connective Tissue Diseases
D017437	Skin and Connective Tissue Diseases
D001327	Autoimmune Diseases
D007154	Immune System Diseases

ID	Title	Description
BG000	Phase 1b: Placebo	Participants were randomized to receive a subcutaneous (SC) dose of placebo. Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits at Days 210, 240, and 270.
BG001	Phase 1b: Cohort 1: BOS161721 20 mg	Participants were randomized to receive a 20 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
BG002	Phase 1b: Cohort 2: BOS161721 60 mg	Participants were randomized to receive a 60 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270
BG003	Phase 1b: Cohort 3: BOS161721 120 mg	Participants were randomized to receive a 120 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270
BG004	Phase 2: Placebo	Participants were randomized to receive a SC dose of placebo (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
BG005	Phase 2: BOS161721 120 mg	Participants were randomized to receive a 120 mg SC dose of BOS161721 (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.
BG006	Total	Total of all reporting groups

ID	Title	Description	Deaths (At Risk)	Serious Events (Affected)	Serious Events (At Risk)	Other Events (Affected)	Other Events (At Risk)
EG000	Phase 1b: Placebo	Participants were randomized to receive a subcutaneous (SC) dose of placebo. Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits at Days 210, 240, and 270.	7	1	7	4	7
EG001	Phase 1b: Cohort 1: BOS161721 20 mg	Participants were randomized to receive a 20 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.	5	0	5	2	5
EG002	Phase 1b: Cohort 2: BOS161721 60 mg	Participants were randomized to receive a 60 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270	9	2	9	7	9
EG003	Phase 1b: Cohort 3: BOS161721 120 mg	Participants were randomized to receive a 120 mg SC dose of BOS161721. Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270	9	0	9	8	9
EG004	Phase 2: Placebo	Participants were randomized to receive a SC dose of placebo (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of placebo on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.	37	3	37	22	37
EG005	Phase 2: BOS161721 120 mg	Participants were randomized to receive a 120 mg SC dose of BOS161721 (as determined from Phase 1b of the study). Participants received a total of 7 SC monthly doses of BOS161721 on Days 0, 30, 60, 90, 120, 150, and 180, followed by safety follow-up visits on at Days 210, 240, and 270.	76	2	76	44	76

Term	Organ System	Source Vocabulary	Assessment Type	Statistical Information
Acute Respiratory Failure	Respiratory, thoracic and mediastinal disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG0030 events0 affected9 at risk EG004
Asthma	Respiratory, thoracic and mediastinal disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Chronic Obstructive Pulmonary Disease	Respiratory, thoracic and mediastinal disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0021 events1 affected9 at risk EG003
Lupus Pneumonitis	Respiratory, thoracic and mediastinal disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Basal Cell Carcinoma	Neoplasms benign, malignant and unspecified (incl cysts and polyps)	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0021 events1 affected9 at risk EG003
Intraductal Proliferative Breast Lesion	Neoplasms benign, malignant and unspecified (incl cysts and polyps)	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Squamous Cell Carcinoma of Skin	Neoplasms benign, malignant and unspecified (incl cysts and polyps)	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0021 events1 affected9 at risk EG003
Anaemia	Blood and lymphatic system disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Exomphalos	Congenital, familial and genetic disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0001 events1 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Biliary Colic	Hepatobiliary disorders	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003
Pyelonephritis Acute	Infections and infestations	MedDRA Version 23.1	Non-systematic Assessment	EG0000 events0 affected7 at risk EG0010 events0 affected5 at risk EG0020 events0 affected9 at risk EG003