Engineering anti-Lewis-Y hu3S193 antibodies with improved therapeutic ratio for radioimmunotherapy of epithelial cancers

EJNMMI Research

Table 2 Blood clearance parameters for ¹²⁵I- and ¹¹¹In-CHX-A″ DTPA-labelled hu3S193 antibodies

Radiolabel	Antibody	t _1/2α (h)	A_α ^a (%ID/g)	t _1/2β (h)	A_β (%ID/g)	AUC^b (%ID/g h)	MRT^c (h)
¹²⁵I-	Wild type	2.5	36.5	140.7	35.3	7304	199.4
	I253A	0.7	18.1	13.2	60.0	1161	18.7
	H310A	0.6	17.7	7.6	74.0	824	10.7
	H435A	1.2	28.8	15.6	56.2	1316	21.7
	I253A/H310A	0.5	15.7	7.3	66.5	710	10.3
¹¹¹In-CHX-A″ DTPA-	Wild type	2.6	37.2	151.5	31.5	7033	214.4
	I253A	2.7	34.1	63.2	44.6	4200	88.46
	H310A	1.5	38.9	24.4	46.9	1732	33.6
	H435A	1.9	39.6	62.2	38.6	3567	87.0
	I253A/H310A	0.5	20.0	9.1	58.7	781	12.9

^aAmplitudes of the two components t _1/2α and t _1/2β are given by A_α and A_β, respectively, where the sum of A_α and A_β is the total %ID/g
^b AUC area under the curve; time integral of the blood uptake
^c MRT mean residence time; used to give a single variable for blood clearance