Ordering Guidance

To measure only the serum concentration of eculizumab, order ECULI / Eculizumab, Serum.

Specimen Required

Patient Preparation:

1. Fasting: 8 hours, preferred but not required

2. Suggest discontinuing natalizumab at least 4 weeks prior to testing for eculizumab quantitation in serum. Patient should consult the healthcare provider who prescribed this drug to determine if discontinuation is an option. If not, ok to proceed with testing while taking natalizumab.

Supplies: Sarstedt Aliquot Tube, 5 mL (T914)

Collection Container/Tube:

Preferred: Red top

Acceptable: Serum gel

Submission Container/Tube: 2 Plastic vials

Specimen Volume: 2 mL Serum in 2 separate plastic vials (see Collection Instructions)

Collection Instructions:

1. Draw blood immediately before next scheduled dose.

2. Immediately after specimen collection, place the tube on wet ice and allow specimen to clot.

3. Centrifuge at 4° C.

4. Aliquot serum into two separate plastic vials, each containing 1 mL.

5. Within 30 minutes of centrifugation, freeze specimen. Serum must be placed on dry ice if not frozen immediately.

Note: If a refrigerated centrifuge is not available, it is acceptable to use a room temperature centrifuge, provided the sample is kept on ice before centrifugation, and immediately afterward, the serum is aliquoted and frozen.