Everolimus Drug Level
Label Mnemonic: EVER
Epic Lab Code: LAB7456
Downtime Form: A-1a Therapeutic Drug Assay Requisition
Chemistry
6240 RCP
356-3527
Specimen(s):
Whole Blood
Specimen Instructions:
Pre dose (trough) levels are recommended.
Collection Medium:
Lavender top tube 3 mL (EDTA)
Minimum:
Preferred Minimum: 3 mL whole blood in lavender (EDTA) tube or TWO lavender top (EDTA) microtubes for pediatric patients.

Absolute Minimum: 0.3 mL whole blood in lavender (EDTA) tube or ONE lavender top (EDTA) microtube for pediatric patients.
Rejection Criteria:
Serum, plasma, clotted samples, and specimens ambient longer than 24 hours.
Testing Schedule:
One batch per day. Cutoff time for same day service is 1200.
Turn Around Time:
Results available by 1600 daily.
Reference Range:
3.0 - 8.0 ng/mL
Interpretive Data:
Zortress®, FDA approved for prophylaxis of organ rejection in adult patients receiving a kidney transplant, has a suggested therapeutic range of 3-8 ng/mL. This range is based on a predose (trough) specimen in patients who are also receiving cyclosporine.

Afinitor® is FDA approved for the treatment of renal cell carcinoma and for the treatment of subependymal giant cell astrocytoma (SEGA) associated with tuberous sclerosis (TS) in patients who are not candidates for curative surgical resection. The suggested therapeutic range for treatment of SEGA is 5-10 ng/mL, which is based on a predose (trough) specimen.

The optimal therapeutic range for a given patient may differ from this suggested range based on the indication for therapy, treatment phase (initiation or maintenance), use in combination with other drugs, time of specimen collection relative to prior dose, type of transplanted organ, and/or the therapeutic approach of the transplant center. Symptoms of toxicity are more likely at predose (trough) concentrations that exceed 15 ng/mL.
Comments:
Everolimus (Zortress®, Certican®, Afinitor®) whole blood concentrations can be measured by either chromatographic or immunoassay methodologies. These two methodologies are not directly interchangeable, and the measured everolimus whole blood concentration depends upon the type of assay used.

Sirolimus (rapamycin) cross-reacts significantly with the everolimus immunoassay. Everolimus blood concentrations cannot be determined reliably in patients whose blood has both sirolimus and everolimus. This can occur when patients are being transitioned from sirolimus to everolimus or everolimus to sirolimus. In transitioning patients from sirolimus to everolimus, the long therapeutic half-life of sirolimus (~2-3 days) should be kept in mind.
Methodology:
Turbidimetric Immunoassay
CPT Code:
80169