Consumption of BAX326 Per Event Per Participant;Study Parts 1 and 3: Area Under the Plasma Concentration/Time Curve From Time 0 to Infinity Per Dose (AUC0-∞/ Dose);Study Parts 1 and 3: Mean Residence Time (MRT);Study Parts 1 and 3: Clearance (CL);Study Parts 1 and 3: Incremental Recovery at Cmax (IR at Cmax);Incremental Recovery (IR) at 30 Minutes Over Time;Change in Incremental Recovery (IR) at 30 Minutes Over Time;Study Parts 1 and 3: Half Life (T 1/2);Study Parts 1 and 3: Volume of Distribution at Steady State (Vss);Study Part 2: Annualized Bleed Rate (ABR) During Treatment With BAX326;Bleeding Episodes Treated With 1, 2 or ≥3 Infusions of BAX326 by Bleeding Site and Cause;Hemostatic Efficacy at Resolution of All Bleeding Episodes (BEs) Treated With BAX326 by Bleeding Site and Cause;Total Weight-adjusted Dose Per Bleeding Episode (BEs) of All BEs Treated With BAX326 by Bleeding Site and Cause;Consumption of BAX326 Per Participant: Median Number of Infusions Per Month;Consumption of BAX326 Per Participant: Median Weight-adjusted Consumption Per Month;Number of Participants Who Developed Inhibitory Antibodies to Factor IX (FIX);Occurrence of Total Binding Antibodies of Indeterminate Specificity (Within Assay Variability);Occurrence of Treatment Related Total Binding Antibodies;Number of Participants Who Experienced Severe Allergic Reactions (e.g. Anaphylaxis);Number of Participants Who Experienced Thrombotic Events;Number of Participants With Clinically Significant Changes in Laboratory Parameters: Clinical Chemistry;Number of Participants With Clinically Significant Changes in Laboratory Parameters: Hematology;Number of Participants With Clinically Significant Changes in Laboratory Parameters: Vital Signs;Number of Participants With Clinically Significant Changes in Laboratory Parameters: Thrombogenic Markers;Number of Adverse Events (AEs) After BAX326 Treatment;Number of Participants With Adverse Events (AEs) After BAX326 Treatment;EuroQoL (Quality of Life)-5 Dimensions (EQ-5D) Total Index Scores;EuroQoL (Quality of Life)-5 Dimensions Visual Analogue Scale (EQ-5D VAS) Scores;General Pain Assessment Through a Visual Analog Scale (VAS);Short Form (36) Health Survey (SF-36): HRQoL 'Physical Component Score' (PCS);SF-36: HRQoL 'Mental Health' (MH);SF-36: HRQoL Physical Functioning' (PF);Health Resource Use - Emergency Room Visits;SF-36: HRQoL Role-Physical (RP);SF-36: HRQoL Role-Emotional;SF-36: HRQoL Bodily Pain;SF-36: HRQoL Mental Health;SF-36: HRQoL Vitality;SF-36: HRQoL Social Functioning;SF-36: HRQoL General Health;Pediatric Quality of Life Questionnaire (PedsQL) Physical Health Summary Score (Ages 12-16);Pediatric Quality of Life Questionnaire (PedsQL) Psychosocial Health Summary Score (Ages 12-16);Pediatric Quality of Life Questionnaire (PedsQL) Total Score (Ages 12-16);Health-Related Quality of Life (HRQoL) Disease-specific: Haem-A-QoL;Health-Related Quality of Life (HRQoL) Disease-specific: Haemo-QoL - Participants On-Demand (Ages 12-16);Health Resource Use - Number of Hospitalizations;Health Resource Use - Total Days of Hospital Stay;Health Resource Use - Unscheduled Doctor's Office Visits;Health Resource Use - Days Lost From Work or School