Study to Evaluate the Efficacy and Safety of PANZYGA in Pediatric Patients With Chronic Immune Thrombocytopenia (ITP)

Inclusion Criteria:

1. Females and males aged from ≥1 year to <18 years old

2. Confirmed diagnosis of Chronic Immune Thrombocytopenia (ITP) according to AmericanSociety of Hematology (ASH) 2019 guidelines

3. Platelets count <30x10^9/L at the Baseline Visit

4. Voluntarily given written informed consent (provided by patient's parent or legalguardian) and assent (provided by patient [if age-appropriate per IRB (InstitutionalReview Board) requirements])

5. Sexually active females who have been using at least 1 acceptable form of birthcontrol for a minimum of 30 days (or a minimum of 3 months for hormonalcontraceptives) prior to the Screening visit and must agree to use at least 1acceptable method of contraception throughout the study and for 30 days after thelast dose of PANZYGA. Acceptable methods of birth control for this study include:intrauterine device (IUD), hormonal contraception, male or female condom, spermicidegel, diaphragm, sponge, or cervical cap. For non-sexually active females who havebegun menstruating, abstinence is considered an acceptable method of birth control.

6. Parent or legal guardian must agree and be willing to assist the participant attendstudy visits, and to follow all protocol requirements and instructions of the studydoctor

Exclusion Criteria:

1. Thrombocytopenia secondary to other diseases (such as Acquired ImmunodeficiencySyndrome [AIDS] or systemic lupus erythematosus [SLE]), drug-relatedthrombocytopenia, or congenital thrombocytopenia

2. Administration of intravenous immunoglobulin (IGIV) or anti-D immunoglobulin within 3 weeks (+/- 3 days) before enrollment

3. Administration of thrombopoietin receptor agonists when the dose has NOT been stablewithin 3 weeks before enrollment and a dosage change is planned before Day 32

4. Administration of oral immunosuppressants when the dose has NOT been stable duringthe preceding 2 months (2 weeks for long-term corticosteroid therapy) and a dosagechange is planned before Day 32 (Note: topical agents and inhaled corticosteroidtherapy use is permitted)

5. Administration of long-term anti-prolific agents or attenuated androgen therapy whenthe dose has NOT been stable during the preceding 2 months and a dosage change isplanned before Day 32

6. Nonresponsive to previous treatment with IGIV or anti-D immunoglobulin

7. Evidence of an active major bleeding episode at Screening

8. Splenectomy in the previous 3 months or planned splenectomy throughout the studyperiod

9. Evans syndrome (experiencing active disease with 2 out of 3 of the following:autoimmune thrombocytopenia, autoimmune hemolytic anemia, and/or autoimmuneneutropenia)

10. Known or suspected human immunodeficiency virus (HIV), hepatitis B virus (HBV),and/or hepatitis C virus (HCV) infections

11. Emergency surgery in the previous 4 weeks

12. Severe liver and/or kidney disease (alanine aminotransferase [ALT] >3x upper limitof normal (ULN), aspartate aminotransferase [AST] >3x upper limit of normal (ULN),and/or creatinine >120 µmol/L)

13. History of severe hypersensitivity to blood or plasma derived products, or anycomponent of the PANZYGA

14. Known immunoglobulin A (IgA) deficiency and antibodies against IgA

15. History of, or suspected alcohol or drug abuse in the previous year

16. Females who are pregnant or nursing

17. Unable or unwilling to comply with the study protocol

18. Receipt of any other investigational medicinal product within 3 months before studyentry

19. Risk factors* for thromboembolic events in whom the risks outweigh the potentialbenefit of PANZYGA treatment.

20. Any other condition(s), that in the Investigator's opinion, make it undesirable forthe patient to participate in the study or may interfere with protocol compliance.

• Risk factors include, but are not limited to: obesity, advanced age,hypertension, diabetes, a history of atherosclerosis/vascular disease orthrombotic events, hyperlipidemia, multiple cardiovascular risk factors,acquired or inherited thrombophilic disorders, prolonged periods ofimmobilization, severe hypovolemia, central venous catheterization, activemalignancy and/or known or suspected hyperviscosity.