Dacomitinib is an oral, once-daily, pan-HER inhibitor. It is an irreversible inhibitor of HER-1 (EGFR), HER-2 and HER-4 tyrosine kinases. Dacomtinib is being evaluated in phase 3 clinical trials against nonsmall-cell lung cancer. Direct comparison with erlotinib did not show superiority of dacomtinib, but subgroup analysis have demonstrated that subgroup with exon 19 deletion had favorable outcomes with dacomitinib. In addition to nonsmall-cell lung cancer dacomtinib is being evaluated against esophagus, head and neck and other neoplasms. Due to its ability to pass through blood-brain barrier, dacomitinib can be used to treat brain tumors.

Neratinib (HKI-272) is a pan-HER inhibitor, this irreversible tyrosine kinase inhibitor binds and inhibits the tyrosine kinase activity of epidermal growth factor receptors, EGFR (or HER1), HER2 and HER4, which leads to reduced phosphorylation and activation of downstream signaling pathways. Neratinib is a modified form of the discontinued compound pelitinib, and was originally being develoAdditionally, phase II development of oral neratinib as a neoadjuvant therapy for breast cancer, as a second-line therapy for non-small cell lung cancer, and for other solid tumours is also in progress in numerous countries worldwide. ped by Wyeth (later Pfizer). Oral neratinib is awaiting approval as an extended adjuvant therapy for breast cancer in the EU and in the US. Blocking HER2 function by a small molecule kinase inhibitor, such as neratinib, represents an attractive alternate strategy for the growth inhibition of HER2-positive tumours.

Lapatinib is a small molecule and a member of the 4-anilinoquinazoline class of kinase inhibitors. It is present as the monohydrate of the ditosylate salt (trade name TYKERB). Lapatinib is dual inhibitor of the EGFR (epidermal growth factor receptor; also called HER1 or ErbB1) and HER2 receptor tyrosine kinases. Lapatinib was developed by GlaxoSmithKline, however, Novartis subsequently acquired all the rights to the drug from GlaxoSmithKline. TYKERB is indicated in combination therapy for the treatment of metastatic breast cancer that overexpresses the HER2 receptor.

Erlotinib hydrochloride (trade name Tarceva, Genentech/OSIP, originally coded as OSI-774) is a drug used to treat non-small cell lung cancer, pancreatic cancer and several other types of cancer. Similar to gefitinib, erlotinib specifically targets the epidermal growth factor receptor (EGFR) tyrosine kinase. It binds in a reversible fashion to the adenosine triphosphate (ATP) binding site of the receptor. Erlotinib has recently been shown to be a potent inhibitor of JAK2V617F activity. JAK2V617F is a mutant of tyrosine kinase JAK2, is found in most patients with polycythemia vera (PV) and a substantial proportion of patients with idiopathic myelofibrosis or essential thrombocythemia. The study suggests that erlotinib may be used for treatment of JAK2V617F-positive PV and other myeloproliferative disorders. The mechanism of clinical antitumor action of erlotinib is not fully characterized. Erlotinib inhibits the intracellular phosphorylation of tyrosine kinase associated with the epidermal growth factor receptor (EGFR). Specificity of inhibition with regard to other tyrosine kinase receptors has not been fully characterized. EGFR is expressed on the cell surface of normal cells and cancer cells.

Gefitinib is an anilinoquinazoline with antineoplastic activity. Gefitinib inhibits the epidermal growth factor receptor (EGFR) tyrosine kinase by binding to the adenosine triphosphate (ATP)-binding site of the enzyme. Thus the function of the EGFR tyrosine kinase in activating the Ras signal transduction cascade is inhibited; and malignant cells are inhibited. Gefitinib is the first selective inhibitor of the EGFR tyrosine kinase which is also referred to as Her1 or ErbB-1. EGFR is overexpressed in the cells of certain types of human carcinomas - for example in lung and breast cancers. Overexpression leads to inappropriate activation of the apoptotic Ras signal transduction cascade, eventually leading to uncontrolled cell proliferation. Gefitinib is used for the continued treatment of patients with locally advanced or metastatic non-small cell lung cancer after failure of either platinum-based or docetaxel chemotherapies.

Canertinib or CI-1033 (N-[4-[N-(3-Chloro-4-fluorophenyl)amino]-7-[3-(4-morpholinyl)propoxy]quinazolin-6-yl]acrylamide) is a pan-erbB tyrosine kinase inhibitor. It selectively inhibits erbB1 (epidermal growth factor receptor), erbB2, erbB3, and erbB4 without inhibiting tyrosine kinase activity of receptors such as platelet-derived growth factor receptor, fibroblast growth factor receptor, and insulin receptor, even at high concentrations. Canertinib was under development by Pfizer Inc as a potential treatment for cancer.

AST-1306, also known as Allitinib, is an orally active potent, selective, irreversible inhibitor of the HER family of receptor tyrosine kinases. AST-1306 inhibits the enzymatic activities of wild-type epidermal growth factor receptor (EGFR) and ErbB2 as well as EGFR resistant mutant in both cell-free and cell-based systems. AST1306 potently suppressed tumor growth in ErbB2-overexpressing adenocarcinoma xenograft and FVB-2/N(neu) transgenic breast cancer mouse models. Allitinib is in Phase I clinical trial for the treatment of advanced solid tumors. Serious adverse effects detected were: diarrhea, dehydration and hyperbilirubinemia.

Tesevatinib (EXEL-7647 or XL647) was optimized as an inhibitor of a spectrum of growth-promoting and angiogenic receptor tyrosine kinases (RTKs) to simultaneously block tumor growth and vascularization. In particular, Tesevatinib potently inhibits the EGF/ErbB2, VEGF, and ephrin RTK families. The drug is being developed by Kadmon Corporation under licence from Symphony Evolution (Symphony Capital Partners). Kadmon is developing tesevatinib for the treatment of autosomal polycystic kidney disease and solid cancers.

Novartis Oncology (previously Novartis) is developing nazartinib (formerly EGF 816), a third generation mutant-selective tyrosine kinase inhibitor (TKI) of epidermal growth factor receptor (EGFR), for the treatment of solid malignancies, with a focus on non-small cell lung cancer. Nazartinib is a covalent mutant-selective EGFR inhibitor, with Ki and Kinact of 31 nM and 0.222 min−1 on EGFR(L858R/790M) mutant, respectively. Upon oral administration, nazartinib covalently binds to and inhibits the activity of mutant forms of EGFR, including the T790M EGFR mutant, thereby preventing EGFR-mediated signaling. This may both induce cell death and inhibit tumor growth in EGFR-overexpressing tumor cells. EGFR, a receptor tyrosine kinase mutated in many tumor cell types, plays a key role in tumor cell proliferation and tumor vascularization. EGF816 preferentially inhibits mutated forms of EGFR including T790M, a secondarily acquired resistance mutation, and may have therapeutic benefits in tumors with T790M-mediated resistance when compared to other EGFR tyrosine kinase inhibitors. As this agent is selective towards mutant forms of EGFR, its toxicity profile may be reduced as compared to non-selective EGFR inhibitors which also inhibit wild-type EGFR.

Naquotinib (ASP8273) is an orally available, irreversible, mutant-selective, epidermal growth factor receptor (EGFR) inhibitor, with potential antineoplastic activity. Naquotinib was found by mass spectrometry to covalently bind to a mutant EGFR (L858R/ T790M) via cysteine residue 797 in the kinase domain of EGFR with long-lasting inhibition of EGFR phosphorylation for 24 h. In the NSCLC cell lines harboring the above EGFR mutations, Naquotinib had IC50 values of 8-33 nM toward EGFR mutants, more potently than that of WT EGFR (IC50 value of 230 nM). In mouse xenograft models, Naquotinib induced complete regression of the tumors after 14 days of treatment. ASP8273 even showed activity in mutant EGFR cell line which is resistant to other EGFR TKIs. Naquotinib is in phase III clinical trials for the oral treatment of EGFR mutated non-small cell lung cancer (NSCLC).