Busulfan Lab (Pharmacokinetics Lab)

Fred Hutch Pharmacokinetics Lab

Lab Hours: Tuesday to Saturday, 8 a.m. to 5 p.m.
Lab closed on Sundays, Mondays and holidays

Phone: 206.606.7389
Fax: 206.606.7397
Email: pklab@fredhutch.org

Please send samples to:
Pharmacokinetics Laboratory
Fred Hutchinson Cancer Center
188 E Blaine Street, Suite 250
Seattle, WA 98102

Provides Therapeutic Drug Monitoring Services

The Fred Hutch Pharmacokinetics Laboratory (PK Lab) is a CAP/CLIA-certified clinical lab that provides therapeutic drug monitoring (TDM) services. We specialize in busulfan TDM, providing individualized drug exposure targeting for patients from over 75 medical institutions in the U.S. and Canada.

Therapeutic drug monitoring (TDM) is the specialized measurement of drug concentrations for medications with a narrow therapeutic window. Drug concentrations are used to assess and adjust medication dosage to optimize therapeutic effectiveness while minimizing adverse effects.

What Do We Offer?

Our lab provides individualized drug exposure targeting for patients from the South Lake Union Clinic, UW Medical Center - Montlake, Seattle Children's and the Veteran's Affairs Medical Center in Seattle. In addition, the laboratory provides TDM services to physicians from other medical institutions throughout the U.S. and Canada.

We collaborate with providers and researchers throughout the country, as well as our alliance partners on clinical research protocols related to PK/PD/pharmacogenomics of various oncology-related agents.

Under specific arrangements via contracting, the PK Lab also provides analytical services for clinical trials or studies from the pharmaceutical industry, government entities and other institutions for research and/or clinical purposes.

Lab Tech

Our Expertise Includes

  • Study design and protocol development
  • Grant writing
  • Assay development/validation
  • Data management/analysis
  • Manuscript preparation/publication

Our Current Analytical Equipment

  • Five GC-MS analytical systems
  • One triple quadrupole LC/MS system

Why Use Our Services?

One-stop service for busulfan targeting: We offer a complete package of services from sample concentration analyses to dose recommendations. As physicians receive our reports, they will be ready to administer the next dose with greater confidence.

Fast turnaround time: Subsequent dose recommendation and busulfan level results are usually available on the same day of the sample’s arrival on-site. A verbal report is delivered by direct telephone communication with the attending physician and/or clinical pharmacist. Then a formal hard-copy report is faxed to designated recipients.

Professional consultation is always available: A pharmacokinetics specialist is always available to answer care provider questions. 

Well-trained staff with extensive experience: We have more than 15 years of experience in busulfan TDM. Every staff member is professionally trained in related scientific or medical fields.


Sending Samples to the Busulfan Laboratory

*This page is designed for referral institutions only.  If you are from Fred Hutch, UW Medicine, CHRMC, or VA Hospitals in the Seattle area, please disregard the information below.

If you already have an account with us, please download the Busulfan Electronic Order Form to your computer and follow its instructions to order busulfan testing. (You need Adobe Acrobat Reader 7.0 or above; click here for a free download.) If you are a new client, please contact us for account set-up.

Advance notice is required for all sample shipments:

  • Tuesday to Saturday arrival: At least 48 hours in advance. Please call or email us to provide package tracking information.
  • Lab closes on Sundays and Mondays.
  • Holidays: Lab closes on all observed holidays and their very next days. Please call 206.606.7389 for details.

Sample collection and processing

  • Draw minimum 1 mL (Pediatric) to 4 mL (Adult) of blood into 4-mL Sodium Heparin green top blood tubes.  
  • Busulfan degrades quickly at room temperature. Each sample should be kept in wet ice slurry or refrigerated at all time. Centrifuge them as soon as possible at 4 °C. Separate the plasma from each sample and transfer it to individual 4mL plastic tubes. Immediately freeze these plasma samples at -20 °C.
  • All samples have to be labeled with patient name, Medical Record #, date and actual clock time of the blood draw. Two unique identifiers and clock times are REQUIRED or samples can be rejected. 
  • Samples must be shipped on a minimum of 3 kg of dry ice using an overnight carrier. Samples that arrived thawed will not be analyzed. 
  • The REQUISITION SHEET for particular regimen, IV Q6 hr or test dose, IV Q24 hr, and Oral Q6 hr is provided below. It is required to be sent with the samples. Patient identifiers must be matched with those on the collected samples mentioned above. Also, our requisition serves as physician’s order and must be signed by the attending physician or designee/caregiver according to the College American Pathologists (CAP) requirement. 


  • We usually release pharmacokinetics results on the same day as receipt of the samples. Average sample run-time is approximately 4 to 6 hours from receiving the package. 
  • Sample processing is prioritized by time zone differences or next dose due time to maximize the advantage of dose adjustments.
  • All results must be verbally delivered to attending physician, pharmacist, or caregiver who is a certified MD or PharmD. No exceptions.
  • After the verbal report, a hardcopy can be faxed to designated number(s). Please click here for an example of our facsimile report. 

CPT Code

  • The current CPT code for busulfan monitoring is 80299. 

New Accounts

When setting up a new account with us for busulfan analysis, please have the following information ready and call 206.606.7389.

  1. Institution information: Name of the institution, address, and general contact numbers.
  2. Billing contact information: Name, title, address with mail stop, phone number and fax number.
  3. Caller information: Name, phone number, and fax number.

Please allow 3 to 4 days for a new account to be properly set up. Patient samples can be sent in before the set up process is completed. Please ask for sample acceptance.