Table 2.

Biochemical IC₅₀ values for inhibition of PDGFRA kinase activity in transfected cells

1° Mutation	2° Mutation	Imatinib	Sorafenib	Sunitinib
WT	None	<100	<100	<100
V561D	None	<100	<100	<100
V561D	D842V	3,100	3,100	>1,000
Del DIMH842-845	None	<100	<100	ND
D842V	None	1,700	1,280	>1,000

NOTE: The values for imatinib, sorafenib, and sunitinib represent the biochemical IC₅₀ expressed in nmol/L units for the listed single mutant or compound mutant kinases. WT indicates the results for wild-type (unmutated), PDGF-AA ligand-stimulated PDGFRA kinase. The IC₅₀ values for imatinib and sorafenib are from direct head-to-head comparisons from a minimum of 3 replicate experiments. The IC₅₀ values for sunitinib are from a previous publication from our group (6). The IC₅₀ for imatinib was not significantly different than the IC₅₀ for sorafenib for any of these mutant kinases.

Abbreviation: ND, not determined.