Due to business reasons, not safety issues

This randomized, multicenter, double-blind (DB), placebo controlled, phase 2 study will evaluate the efficacy and safety of IgPro10. The DB Treatment Period will be followed by a 24-week Open-label (OL) Treatment Period.

Eligible subjects will be randomized at Baseline in a 2:1 ratio of treatment IgPro10 or placebo in the DB Treatment Period. All subjects who enter OL Treatment Period will receive IgPro10.

Inclusion Criteria:

• 1. Age ≥18 years (male or female) at time of providing written informed consent
• Documented diagnosis of SSc according to ACR / EULAR criteria 2013
• mRSS ≥ 15 and ≤ 45
• Disease duration ≤ 5 years defined as the time from the first non-Raynaud's phenomenon manifestation
• Subjects within first 18 months of disease duration from first non-Raynaud's phenomenon manifestation.

Exclusion Criteria:

• Primary rheumatic autoimmune disease other than dcSSc, including but not limited to rheumatoid arthritis, systemic lupus erythematosus, mixed connective tissue disorder, polymyositis, and dermatomyositis, as determined by the investigator Note: Subjects with fibromyalgia, secondary Sjogren's syndrome, and scleroderma-associated myopathy or myositis at Screening are not excluded
• Positive anti-centromere autoantibodies at Screening
• Evidence of severe chronic kidney disease with estimated glomerular filtration rate < 45 mL/min/1.73 m2 (as calculated by the Chronic Kidney Disease Epidemiology Collaboration equation) or receiving dialysis. Additionally, subjects with current confirmed diagnosis of diabetes mellitus and requiring medication, with eGFR < 90 mL/min/1.73m2 will be excluded from the study.
• History of documented thrombotic episode eg, PE, DVT, myocardial infarction, thromboembolic stroke at any time Note: past superficial thrombophlebitis more than two years from Screening is not exclusionary
• Documented thrombophilic abnormalities including blood hyperviscosity, protein S or protein C deficiency, anti-thrombin-3 deficiency, plasminogen deficiency, antiphospholipid syndrome, Factor V Leiden mutation, dysfibrinogenemia, or prothrombin G20210A mutation
• Greater than 3 specified current risk factors for TEEs (documented and currents conditions): atrial fibrillation, coronary disease, diabetes mellitus, dyslipidemia, hypertension, obesity (Body Mass Index ≥ 30 kg/m2), recent significant trauma, and immobility (wheelchair-bound or bedridden)
• Ongoing active serious infection at Screening (including, but not limited to, pneumonia, bacteremia/septicemia, osteomyelitis/septic arthritis, bacterial meningitis, or visceral abscess)
• Malignancy in the past 2 years, except for non-melanoma skin cancer, cervical carcinoma in situ, or other in situ cancer if it has been excised and treated within in the past year
• Known hypoalbuminemia, protein-losing enteropathies, and any proteinuria (defined by total urine protein concentration > 0.2 g/L)
• Known IgA deficiency or serum IgA level < 5% lower limit of normal

CSL will consider requests to share Individual Patient Data (IPD) from systemic review groups or bona-fide researchers. For information on the process and requirements for submitting a voluntary data sharing request for IPD, please contact CSL at clinicaltrials@cslbehring.com.

Applicable country specific privacy and other laws and regulations will be considered and may prevent sharing of IPD.

If the request is approved and the researcher has executed an appropriate data sharing agreement, IPD that has been appropriately anonymized will be available.

IPD requests may be submitted to CSL no earlier than 12 months after publication of the results of this study via an article made available on a public website.

Requests may only be made by systematic review groups or bona-fide researchers whose proposed use of the IPD is non-commercial in nature and has been approved by an internal review committee.

An IPD request will not be considered by CSL unless the proposed research question seeks to answer a significant and unknown medical science or patient care question as determined by CSL's internal review committee.

The requesting party must execute an appropriate data sharing agreement before IPD will be made available.