Safety of DefenCath (taurolidine‑heparin) catheter lock in children on chronic hemodialysis

Inclusion Criteria:

* All participants must be \< 18 years of age and must meet the following inclusion criteria:
* The investigator, or a person designated by the investigator, will obtain written informed consent from each study participant's legal guardian and the participant's assent, when applicable, before any study-specific activity is performed. All legal guardians should be fully informed, and participants should be informed to the fullest extent possible, about the study in language and terms they are able to understand.
* A legal guardian or primary caregiver must be available to help the study-site personnel ensure follow up; accompany the participant to the study site on each assessment day according to the schedule of activities (SoA) (e.g., able to comply with scheduled visits, treatment plan, laboratory tests and other study procedures); consistently and consecutively be available to provide information on the participant during the scheduled study visits; accurately and reliably dispense study intervention as directed.
* The participant has kidney failure and undergoes chronic hemodialysis (HD) at least 2 times per week.
* The participant has an HD central venous catheter (CVC) and is placed in a jugular or subclavian vein.
* The participant has demonstrated the ability to achieve an appropriate minimum blood flow (Qb) for the participant's relative age and weight for at least 2 consecutive dialysis sessions to enable successful HD.
* The participant is likely to require the use of a CVC for at least 60 days, based on clinical assessment.
* The participant is willing to comply with specified follow-up evaluations and prescribed dialysis therapy.
* The participant is not expected to expire within 180 days, based on clinical assessment.
* Female participants of childbearing potential:
* Must agree to abide by contraception requirements, must not be lactating, and avoid pregnancy during study participation from the first Screening visit until 30 days after the last administration of study treatment.
* Must commit to an additional method of birth control in addition to male partners agreeing to use condoms with spermicide, throughout the study including for at least 30 days after the last administration of study treatment:
* True abstinence: Refraining from heterosexual intercourse when this is in line with the preferred and usual lifestyle of the participant (periodic abstinence \[e.g., calendar, ovulation, symptothermal, post ovulation methods\] and withdrawal are not acceptable).

Combined (containing estrogen and progestogen) hormonal birth control (oral, intravaginal, injectable, or transdermal) associated with inhibition of ovulation initiated at least 30 days before dose administration.

* Progestogen only hormonal birth control (oral, injectable, or implantable) associated with inhibition of ovulation initiated at least 30 days before study dose administration.
* Bilateral tubal occlusion/ligation.
* Intrauterine device.
* Intrauterine hormone releasing system.
* Vasectomized partner.
* NOTE: If the childbearing potential changes after start of the study (e.g., a premenarchal female participant experiences menarche) or the risk of pregnancy changes (e.g., a female participant who is not heterosexually active becomes active), the participant must discuss this with the investigator, who should determine if a female participant must begin a highly effective method of contraception, or a male participant must use a condom. If reproductive status is questionable, additional evaluation should be considered.
* Male participants who are sexually active with a female partner of childbearing potential must agree to use male condoms and spermicide, even if the male participant has undergone a successful vasectomy (males with vasectomy can use condoms without spermicide), from Day 1 until at least 30 days after the last administration of study treatment.

Exclusion Criteria:

* Any participant who is currently receiving systemic antibiotics. Topical antibiotic use is permitted.
* Visible evidence of compromised skin integrity is present at the catheter exit site or evidence of a catheter exit site infection.
* The participant has received any thrombolytic treatment (i.e., tissue plasminogen activator \[tPA\] - Cathflo®), not as part of the institution's standard of care for patency management, in their current catheter within 30 days of randomization.
* The fill volume of catheter lumen(s) is unknown or cannot be determined.
* The participant uses any type of antimicrobial-coated or heparin-coated catheter.
* Documented chronic bleeding diathesis, active or recurrent bleeding within 30 days prior to randomization.
* Documented history of an atrial thrombus or known hypercoagulable state.
* The participant has open, non-healing skin ulcers.
* Any participant who has received an allogeneic hematopoietic stem cell transplant within the last year.
* The participant has current requirement for systemic chemotherapy and/or immunosuppression and absolute neutrophil count \<500 cells/µL that occurred in the past 4 weeks.
* An active malignancy that either in and of itself or by virtue of its treatment with chemotherapy or biologic therapy results in neutropenia, leukopenia and/or immunosuppression.
* Known allergy or absolute contraindication to taurolidine, citrate, or heparin, or a history of heparin induced thrombocytopenia (HIT).
* Unstable malignancy.
* Cirrhosis with encephalopathy.
* The participant is currently taking another medication with known systemic drug interaction with taurolidine, citrate, or heparin.
* The participant is anticipated to receive a renal transplant within 90 days (participants can be on the transplant list, but a participant with a known or anticipated transplant date within the next 90 days should be excluded).
* The participant has a clinically significant cardiac rhythm or functional disorder.
* The participant has severe hypoxemia, respiratory acidosis, asphyxia, or hypotension prior to randomization based on assessment of the investigator.
* Any other medical condition which renders the participant unable to or unlikely to complete the study, or which would interfere with optimal participation in the study or produce significant risk to the participant.