The purpose of this observational, multi-center, retrospective cohort study is to assess treatment patterns of Cuvitru (SCIG) 20 percent (%) and HyQvia (fSCIG) in polish pediatric participants with PID. The study will collect pediatric patient data. These data are gathered and collected during routine clinical care. As this is a non-interventional/observational study, no treatment/pharmacotherapy is provided as part of the study.

Subcutaneous immune globulin (SCIG 20%) and facilitated subcutaneous immunoglobulin (fSCIG) treatment in Polish paediatric patients with primary immunodeficiencies (PID) - retrospective medical chart review study

Inclusion Criteria:

Participant eligibility is determined according to the following criteria prior to entry into the study:

• The participant or, when applicable, the participant's legally acceptable representative signs and dates a written, informed consent form and any required privacy authorization prior to the initiation of any study procedures.
• Male or female participants with PID, aged less than (<)18 years treated with SCIG 20% or fSCIG..
• Diagnosis of PID according to the criteria developed by the European Society for Immunodeficiencies (ESID) https://esid.org/About-ESID
• Treatment period for 20% SCIG ranges from November 1, 2017 until June 30, 2020, and for fSCIG from July 1, 2018 until June 30, 2020.

Exclusion Criteria:

• None

Participants with PID on treatment with SCIG 20% or fSCIG will be included in this study.

Takeda provides access to the de-identified individual participant data (IPD) for eligible studies to aid qualified researchers in addressing legitimate scientific objectives (Takeda's data sharing commitment is available on https://clinicaltrials.takeda.com/takedas-commitment?commitment=5). These IPDs will be provided in a secure research environment following approval of a data sharing request, and under the terms of a data sharing agreement.

IPD from eligible studies will be shared with qualified researchers according to the criteria and process described on https://vivli.org/ourmember/takeda/. For approved requests, the researchers will be provided access to anonymized data (to respect patient privacy in line with applicable laws and regulations) and with information necessary to address the research objectives under the terms of a data sharing agreement.