Table 2.

Inhibitory profiles of FDA-approved ErbB family-targeted TKIs approved for BC and NSCLC^a [25, 26]

Agent	Target(s)	IC50, nM
Gefitinib	EGFR	0.5–33
Erlotinib	EGFR	0.6–0.8
Lapatinib	EGFR	0.3–17
	HER2	6–25
Afatinib	EGFR	0.5
	HER2	14
	HER4	1
Neratinib	EGFR	92
	HER2	59
	HER4	NR
Osimertinib	WT EGFR	184
	T790M EGFR	1

BC breast cancer, IC₅₀ drug concentration causing 50% inhibition of the desired activity in in vitro EGFR kinase assays, EGFR epidermal growth factor receptor, HER2 human epidermal growth factor receptor 2, HER4 human epidermal growth factor receptor 4, NR not reported, NSCLC non-small cell lung cancer, TKI tyrosine kinase inhibitors, WT wild type

^aThe measurement of IC₅₀ values is dependent on the assay; direct, cross-assay comparisons should be interpreted carefully