Please assess the completion status of the following clinical trial:

Trial Title: Study of Recombinant Coagulation Factor IX Fc Fusion Protein, BIIB029, in Previously Treated Pediatric Participants With Hemophilia B

Study Design Characteristics:
- Allocation: None
- Intervention Model: SINGLE_GROUP
- Observational Model: None
- Primary Purpose: TREATMENT
- Time Perspective: None
- Masking: NONE
- Phase: PHASE3
- Number of Arms: 1.0

Eligibility Criteria:
Key Inclusion Criteria:~* Severe hemophilia B defined as ≤ 2 IU/dl (≤ 2%) endogenous FIX~* Male \< 12 years and weight ≥ 13 kg~* History of at least 50 documented prior exposure days to FIX~* No history of, or currently detectable, inhibitor~Key Exclusion Criteria:~* Other coagulation disorders in addition to Hemophilia B~* History of anaphylaxis associated with any FIX or IV immunoglobulin administration~NOTE: Other protocol defined Inclusion/ Exclusion criteria may apply.

- Gender: MALE
- Minimum Age: None
- Maximum Age: 11 Years
- Healthy Volunteers: f

Study Arms:
- rFIXFc Prophylaxis (Type: EXPERIMENTAL): At Baseline and at Day 1, participants receive a single intravenous (IV) injection of prestudy FIX and rFIXFc, respectively, over 10 (±5) minutes at a dose of 50 IU/kg. Immediately after the last PK sampling, the first prophylactic dose of approximately 50 to 60 IU/kg will be administered in clinic as an IV injection.~Dose could be increased or decreased in increments of 10 IU/kg; increases to a maximum of 100 IU/kg and frequency of administration to a maximum of twice weekly, were allowed as indicated.

Based on this trial design, predict the completion outcome and termination type (if applicable).