Test ID ECULI Eculizumab, Serum
Ordering Guidance
Therapeutic drug monitoring of eculizumab may be useful when assessing response to therapy is difficult, or patients need to be above a certain therapeutic monoclonal antibody (mAb) concentration in order to improve the odds of a clinical response for therapy optimization, including potential dose de-escalation or discontinuation of therapy in remission states. Pharmacodynamic studies of complement blockage are also common, see ECUMP / Eculizumab Monitoring Panel, Serum for more information on related testing.
Specimen Required
Patient Preparation: Pembrolizumab/Keytruda must be discontinued at least 4 weeks prior to testing for eculizumab quantitation in serum.
Container/Tube:
Preferred: Red top
Acceptable: Serum gel
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
Collection Instructions:
1. Collect blood immediately before next scheduled dose.
2. Centrifuge and aliquot serum into plastic vial within 2 hours of collection.
Useful For
Assessing the response to eculizumab therapy
Assessing the need for dose escalation
Evaluating the potential for dose de-escalation or discontinuation of therapy in remission states
Monitoring patients who need to be above a certain eculizumab concentration in order to improve the odds of a clinical response for therapy optimization
Method Name
Liquid Chromatography-Tandem Mass Spectrometry, High-Resolution Accurate Mass (LC-MS/MS HRAM)
Reporting Name
Eculizumab, SSpecimen Type
SerumSpecimen Minimum Volume
0.5 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 28 days | |
Frozen | 30 days | ||
Ambient | 4 days |
Reference Values
Lower limit of quantitation =5.0 mcg/mL
>35 Therapeutic concentration for paroxysmal nocturnal hemoglobinuria (PNH)
>50 Therapeutic concentration for atypical hemolytic uremic syndrome (aHUS)
Day(s) Performed
Wednesday
Report Available
3 to 9 daysPerforming Laboratory

Test Classification
This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
80299
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
ECULI | Eculizumab, S | 90240-3 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
65676 | Eculizumab, S | 90240-3 |
Forms
If not ordering electronically, complete, print, and send 1 of the following forms with the specimen:
-Renal Diagnostics Test Request (T830)
-Coagulation Test Request (T753)
-Therapeutics Test Request (T831)