Efficacy, Safety, Tolerability, Immunogenicity and Pharmacokinetic Evaluation of HYQVIA in Pediatric PIDD Subjects

Inclusion Criteria:

1. Participant must have a documented diagnosis of a form of primary immunodeficiency
(PI) involving a defect in antibody formation and requiring gammaglobulin replacement,
as defined according to the International Union of Immunological Societies (IUIS)
Scientific Committee 2015 1 prior to enrollment. The diagnosis must be confirmed by
the sponsor´s Medical Director prior to first treatment with IP in the study.

2. Participant is at least two and below 16 years of age at the time of screening.

3. Participant has been receiving a consistent dose of Immunoglobulin G (IgG),
administered in compliance with the respective product information for a period of at
least three months prior to screening. The average minimum pre-study dose over that
interval was equivalent to 300 mg/kg BW / 4 weeks and a maximum dose equivalent to
1000 mg/kg body weight (BW) / 4 weeks.

4. Participant has a serum trough level of IgG > 5 g/L at screening.

5. If female of childbearing potential, participant presents with a negative pregnancy
test and agrees to employ adequate birth control measures for the duration of the
study.

6. Participant /legally authorized representative is willing and able to comply with the
requirements of the protocol.

Exclusion Criteria:

1. Participant has a known history of or is positive at screening for one or more of the
following: hepatitis B surface antigen (HBsAg), polymerase chain reaction (PCR) for
hepatitis C virus (HCV), PCR for human immunodeficiency virus (HIV) Type 1/2.

2. Abnormal laboratory values at screening meeting any one of the following criteria
(abnormal tests may be repeated once to determine if they are persistent):

1. Persistent alanine aminotransferase (ALT) and aspartate aminotransferase (AST) >
2.5 times the upper limit of normal (ULN) for the testing laboratory

2. Persistent severe neutropenia (defined as an absolute neutrophil count [ANC] ≤
500/mm^3)

3. Participant has anemia that would preclude phlebotomy for laboratory studies,
according to standard practice at the site.

4. Participant has an ongoing history of hypersensitivity or persistent reactions
(urticaria, breathing difficulty, severe hypotension, or anaphylaxis) following
intravenous (IV) immunoglobulin, subcutaneous (SC) immunoglobulin, and/or Immune Serum
Globulin (ISG) infusions.

5. Participant has severe Immunoglobulin A (IgA) deficiency (less than 7.0 mg/dL) with
known anti-IgA antibodies and a history of hypersensitivity.

6. Participant has a known allergy to hyaluronidase.

7. Participant has active infection and is receiving antibiotic therapy for the treatment
of infection at the time of screening.

8. Participant has a bleeding disorder or a platelet count less than 20,000/μL, or who,
in the opinion of the investigator, would be at significant risk of increased bleeding
or bruising as a result of SC therapy.

9. Participant has severe dermatitis that would preclude adequate sites for safe product
administration in the opinion of the investigator.

10. Participant has participated in another clinical study involving an IP or
investigational device within 30 days prior to enrollment or is scheduled to
participate in another clinical study involving an IP or investigational device during
the course of this study.

11. Participant is a family member or employee of the investigator.

12. If female, participant is pregnant or lactating at the time of enrollment.