Drug	Drug target	Cancer type (or types)	Somatic markers
Cetuximab	EGFR	Colorectal, head and neck	EGFR and KRAS
Erlotinib	EGFR	Lung, pancreatic	EGFR
Exemestane	Aromatase	Breast	ESR1, ESR2 and PGR
Gefitinib	EGFR	Lung	EGFR
Imatinib	BCR–ABL, KIT and PDGFRa tyrosine kinases	Chronic myeloid leukaemia, gastrointestinal	Philadelphia chromosome, KIT and PDGFRA
Lapatinib	ERBB2 receptor	Breast	ERBB2
Letrozole	Aromatase	Breast	ESR1, ESR2 and PGR
Panitumumab	EGFR	Colorectal	EGFR and KRAS
Tamoxifen	Oestrogen receptor	Breast	ESR1, ESR2 and PGR
Trastuzumab	ERBB2 receptor	Breast, stomach	ERBB2