Gammagard Liquid and rHuPH20 in PID

Inclusion Criteria:

- Participant is 2 years or older at the time of screening

- Written informed consent obtained from either the participant or the participant's
legally acceptable representative prior to any study-related procedures and study
product administration

- Participant has been diagnosed with a PID disorder requiring antibody replacement as
defined by WHO criteria

- Participant has completed or is about to complete Baxter Clinical Study Protocol No.
160601 or has been receiving a regular IGIV-treatment at mean intervals of 21 ± 3 days
or 28 ± 3 days, or SC at mean intervals of 5 to 16 days, over a period of at least 3
months prior to enrollment at a minimum dose of 300 mg/kg BW/4 weeks

- Participant has a serum trough level of IgG > 4.5 g/L at the last documented
determination

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

- Participant is willing and able to comply with the requirements of the protocol

Exclusion Criteria:

- Participant has a known history of or is positive at enrollment or 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

- Participant has levels of alanine aminotransferase (ALT) or aspartate amino
transferase (AST) > 2.5 times the upper limit of normal for the testing laboratory

- Participant has persistent severe neutropenia (defined as an absolute neutrophil count
[ANC] <= 500/mm3)

- Participant has creatinine clearance (CLcr) values, calculated according to the
formula below, which are < 60% of normal for age and gender for males: CLcr = [(140 -
Age(years)) * (body weight (kg))] / [72 * (serum creatinine (mg/dL))] for females:
CLcr = [(140 - Age(years)) * (body weight(kg)) * 0.85] / [72 * (serum creatinine
(mg/dL))]

- Participant has been diagnosed with, or has a malignancy (other than adequately
treated basal cell or squamous cell carcinoma of the skin or carcinoma in situ of the
cervix) within the last 12 months prior to enrollment; participants treated with
immunosuppressive chemotherapeutic agents during this period are excluded

- Participant has a history of thrombotic episodes (including deep vein thrombosis,
myocardial infarction, cerebrovascular accident, pulmonary embolism) within the last
12 months

- Participant has abnormal protein loss (protein losing enteropathy, nephrotic syndrome)

- Participant has anemia that would preclude phlebotomy for laboratory studies

- Participant has received any blood or blood product other than an IGIV, SC
immunoglobulin, immune serum globulin (ISG) preparation, or albumin within the 6
months prior to enrollment

- Participant has an ongoing history of hypersensitivity or persistent reactions
(urticaria, breathing difficulty, severe hypotension, or anaphylaxis) following IGIV,
SC immunoglobulin, and/or ISG infusions

- Participant has immunoglobulin A (IgA) deficiency and known anti IgA antibodies

- Participant is on preventative (prophylactic) antibiotics and cannot stop antibiotics
at the time of enrollment

- Participant has active infection who started on antibiotic therapy for the treatment
of infection within 7 days prior to screening

- Participant has a bleeding disorder or is on anti-coagulation therapy that results in
a platelet count less than 20,000/μL or International Normalized Ration (INR) > 2X
control, or who, in the opinion of the investigator would be at significant risk of
increased bleeding or bruising as a result of SC therapy

- Participant has total protein > 9 g/dL and participants with myeloma,
macroglobulinemia (IgM) and paraproteinemia

- Participant has a known allergy to hyaluronidase

- If female, participant is pregnant or lactating at the time of study enrollment

- Participant has participated in another clinical study involving an investigational
product (IP) or device within 30 days prior to study enrollment or is scheduled to
participate in another clinical study involving an IP or device during the course of
this study; exception: Baxter Study No. 160601

- Severe dermatitis that would preclude adequate sites for safe product administration