• Fasting specimens are preferred

Fasting for a blood test

• Suggest discontinuing natalizumab at least 4 weeks prior to testing for eculizumab quantitation in serum

Red serum vial/tube, 5 mL

• Recommended timeframe for the blood collection is a trough, or immediately prior to next scheduled dose
• Immediately after specimen collection, place the tube on wet ice.\

1. Allow specimen to clot while on wet ice
2. Spin
3. Transfer serum to two (2) Screw cap transfer vial/tube (Mayo T465)
4. Freeze specimen within 30 minutes.

Screw cap transfer vial/tube (Mayo T465) x2

Frozen (strict) - 14 days

Refrigerated - NO

Ambient - NO

• Gross hemolysis or lipemia
• Serum gel (SST) tubes

• Enzyme-Linked Immunosorbent Assay (ELISA)
• Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
• High Resolution Accurate Mass

Eculizumab Complement Blockage:

> or =46% normal

Eculizumab:

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)