Busulfan (Busulfex®) is an alkylating drug used as a conditioning regimen prior to allogeneic hematopoietic stem cell transplantation. Busulfan has wide inter- and intra-patient pharmacokinetic variability resulting in variable exposure leading to increased risk of toxicities or sub-optimal treatment outcomes. Therapeutic drug monitoring of busulfan using patient plasma samples would benefit clinicians by providing the ability to personalize the dose to achieve a target busulfan exposure.

This protocol is sponsored by Saladax Biomedical, Inc (SBI). The protocol involves the use of sodium heparin plasma sample collected from human subjects receiving intravenous busulfan treatment for the use in the development of a diagnostic test for this drug. A subset of 10 enrolled subject samples will be tested on site using an automated immunoassay MyCareTM Oncology Busulfan Assay Kit manufactured by SBI.

Inclusion Criteria:

1. Pediatric and adult female or male subjects;
2. Current treatment with intravenous busulfan with documentation of diagnosed malignant hematologic or non-malignant disease condition requiring treatment;
3. Adult participants must be capable of understanding and providing written informed consent, approved by an Institutional Review Board (IRB) prior to the initiation of any screening or study-specific procedures. Participants less than 18 years old must provide written assent with appropriate consent provided by legal guardian, who must be capable of understanding and providing informed consent, per Institutional Review Board (IRB) procedures, prior to the initiation of any screening or study-specific procedures.

Exclusion Criteria:

1. Unwilling or unable to follow protocol requirements or to give written informed consent;
2. Patients receiving oral busulfan (e.g., Myleran®) treatment.

Up to 150 unique subjects across participating sites consisting of males and females who meet the protocol Inclusion/ Exclusion criteria as described above. Multiple (3 to 12) plasma samples by venous draw will be collected from each subject for a single day of busulfan dosing. Sample collection timing used to inform dose calculation shall be performed per the site standard of clinical care for patients prescribed busulfan.