Linifanib (ABT-869) is a structurally novel, receptor tyrosine kinase (RTK) inhibitor that is a potent inhibitor of members of the vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF) receptor families, but has much less activity against unrelated RTKs, soluble tyrosine kinases, or serine/threonine kinases. Linifanib (ABT-869) does not have a general antiproliferative effect due to its high dose requirement. However, it may exhibit potent antiproliferative and apoptotic effects on tumor cells whose proliferation is dependent on mutant kinases, such as FMS-related tyrosine kinase receptor-3 (FLT3). Linifanib (ABT-869) was in phase III clinical trial for the treatment of hepatocellular carcinoma, but the study failed to meet the primary end point.

Melogliptin (EMD 675992 or GRC 8200) is an orally bioavailable dipeptidyl peptidase IV (DPP IV) inhibitor. Melogliptin was undergoing phase II clinical trials at Glenmark Pharmaceuticals and Merck KGaA for the treatment of type 2 diabetes. The completed 12 week Phase IIb clinical trial in 494 patients with type 2 diabetes melogliptin improved glycemic control in patients with type 2 diabetes mellitus and exhibited excellent safety and tolerability profile.

Arofylline, a phosphodiesterase 4 inhibitor, participated in clinical trials phase III to treat patients with chronic obstructive pulmonary disease. Besides, in Spain, this drug participated in clinical trials for patients with asthma.

Sardomozide (previously known as SAM486A or CGP-48664) was developed as an inhibitor of S-adenosyl-methionine-decarboxylase, a key enzyme for polyamine biosynthesis. Sardomozide possessed the broad-spectrum antiproliferative and antitumor activity. The drug participated in a phase II clinical trial as a monotherapy in patients with refractory or relapsed non-Hodgkin's lymphoma. In Phase II clinical trial in patients with metastatic melanoma, the drug didn’t have significant therapeutic potential. The further development of this drug was discontinued.

Ibiglustat (GZ/SAR402671 or Genz-682452) is a small molecule inhibitor of glucosylceramide synthase. Ibiglustat has been demonstrated to effectively lower glycosphingolipid synthesis. Genzyme, a Sanofi Company is developing Ibiglustat for the treatment of Parkinson's Disease, Gaucher Disease, and Fabry Disease.

Efegatran (GYKI 14766; LY 294468) is a tripeptide D-methyl-phenylalanyl-prolyl-arginal thrombin inhibitor. It was developed by IVAX for the potential treatment of thromboembolic disorders, mainly myocardial infarction. However, information about the further development is not available.

Gimatecan is a topoisomerase I inhibitor that is presently tested in phase II of clinical trials for the treatment of different cancers: glioma, glioblastoma, epithelial ovarian cancer, fallopian tube or peritoneal cancer. The drug recieved orphan designation for the treatment of glioma.

Pelitrexol (also known as AG2037) was developed by Pfizer as a glycinamide ribonucleotide formyltransferase inhibitor. This drug was studied in phase II clinical trials in patients with metastatic non-small cell lung cancer and in patients with metastatic colorectal cancer who failed treatment. In addition, the drug participated in a phase I clinical trial in treating patients who have advanced, metastatic, or recurrent solid tumors. Information about the further development of pelitrexol is not available.

Edatrexate (10-ethyl-10-deazaaminopterin or 10-EDAM) is an analog of methotrexate with improved pre-clinical antitumor activity, more selective cellular uptake, and with the more extensive formation of intracellular polyglutamate metabolites. This drug is a new dihydrofolate reductase inhibitor, which was studied in phase II clinical trial for the patients with different cancers. The studies were discontinued, for example, in advanced renal cell carcinoma edatrexate in the investigated dose and schedule had minimal activity and was toxic. In case of non-small-cell lung cancer, the dosing schedule of edatrexate did not appear to be improved compared to other chemotherapeutic regimens. In addition, edatrexate was involved in the experiment for the treatemnt of rheumatoid arthritis, but this study was also discontinued.

Saracatinib (AZD0530) is an oral, dual inhibitor of c-Src/Abl kinases initially developed by AstraZeneca for the treatment of cancer. The drug was tested for many neoplasms and reached phase III for ovarian cancer (in combination with paclitaxel), however without demonstrating any significant effect. Sarcatinib is also tested in patients with Alzheimer's Disease (Phase II). Its effect on Alzheimer's Disease patients is explained by inhibition of another kinase, Fyn, which is highly expressed in brain.