DESCRIPTION

Used for the quantitative determination of Anti-Sarilumab concentration in serum and plasma.

PRINCIPLE OF THE ASSAY

This assay employs the quantitative sandwich enzyme immunoassay technique. Sarilumab has been pre-coated onto a microplate. Samples or standards are pipetted into microwells and Anti-Sarilumab will be captured by immobilized Sarilumab. After washing away any unbound substances, a biotin-labeled Sarilumab is added to the wells. After washing away any unbound substances, Streptavidin-HRP is added to the wells. Following a wash to remove any unbound enzyme reagent, a substrate solution is added to the wells and color develops in proportion to the amount of Anti-Sarilumab bound in the initial step. The color development is stopped and the intensity of the color is measured.

PRECISION

Intra-Assay Precision (Precision within an assay): <10% Three samples of known concentration were tested sixteen times on one plate to assess intra-assay precision. Inter-Assay Precision (Precision between assays): <15% Three samples of known concentration were tested in twenty four separate assays to assess inter-assay precision.

Sample		1	2	3	1	2	3
n		16	16	16	24	24	24
Mean (ng/mL)		26.3	5.9	1.2	22.4	5.7	1.3
Standard deviation		1.3	0.6	0.1	1.4	0.4	0.2
CV \(%\)		4.8	9.9	9.9	6.3	6.6	14.5

RECOVERY

The recovery of Anti-Sarilumab spiked to three different levels in human serum samples throughout the range of the assay was evaluated.

Sample	Dilution factor	Average (%)	Range (%)
Human serum (n=3)	1:10	94	83-111
	1:20	86	81-94

LINEARITY

To assess the linearity of the assay, human serum samples were spiked with high concentrations of Anti-Sarilumab and diluted with the Standard Diluent to produce samples with values within the dynamic range of the assay.

Sample	Dilution factor	Average (%)	Range (%)
Human serum (n=4)	1:2	96	90-108
	1:4	95	92-101
	1:8	99	86-106
	1:16	103	90-109