TABLE 1

Antitumor Activity of ¹³¹I-Labeled Anti-FR Antibodies After Systemic Administration in Subcutaneous Tumor Models

						Antitumor activity over untreated animals
Experiment no.	Radiolabelled reagent	Total dose (MBq)	Days of treatment	Tumor	Antigen expression	Percentage tumor volume^*	P	Percentage tumor weight^*	P
1	AFRA-DFM5.3 (Fig. 2A)	37	+6	A431FR	Positive	38	<0.0001	49	0.0303
		37	+6	A431MK	Negative	93	0.3461	82	0.1354
2	AFRA-DFM6.1	37	+6	A431FR	Positive	90	0.6422	81	0. 3455
3	AFRA-DFM5.3 (Fig. 2B)	74	+7 and +13	A431FR	Positive	37	<0.0001	44	0.0015
		74	+7 and +13	A431MK	Negative	76	0.2391	70	0.0637
4	AFRA-DFM6.1	74	+7 and +13	A431FR	Positive	81	0.3186	72	0.1381
5	chi-MOv18 Fab2 (Fig. 2C)	37	+7	A431FR	Positive	11	0.0005	18	0.0002
		37	+7	A431MK	Negative	81	0.5090	81	0.2960

↵* Ratio of tumor volume or weight in treated vs. control mice × 100 measured at experiment end; analyzed with unpaired Student t test. Number of animals: treated, 6–7; controls, 6–8. Some intra- and interassay variability was observed in tumor volume and weight in control mice at 20–23 d after tumor injection: A431FR, 280–630 mm³ and 0.5–1.5 g; A431MK: 310–700 mm³ and 0.3–1.5 g.