Bemarinone (ORF 16600) is a positive inotropic and vasodilator agent with potential clinical utility in the management of congestive heart failure. The compound selectively and competitively inhibited cyclic AMP phosphodiesterase fraction III. However, further studies were discontinued

Lidorestat is a highly potent and selective aldose reductase inhibitor with good oral bioavailability that is reported to improve nerve conduction and reduce cataract formation. Lidorestat reduced mortality rates in hAR transgenic mice. Mice receiving lidorestat had similar survival rates as nonhAR-expressing diabetic mice. Lidorestat treatment did not affect plasma lipids, glucose, or weights of diabetic mice. Drugs such as lidorestat will improve human health by reducing the production of toxic products of the polyol pathway. Lidorestat was developed for the treatment of diabetic complications, including neuropathy, retinopathy, cataracts, nephropathy.

LAROMUSTINE is a sulfonylhydrazine alkylating agent. It is metabolized to yield a chloroethylating compound (VNP-4090-CE) and a carbamoylating compound (methyl isocyanate). The former is primarily responsible for the antineoplastic effect of LAROMUSTINE. It alkylates the O6 position of guanine, resulting in DNA crosslinking, strand breaks, chromosomal aberrations, and disruption of DNA synthesis. The carbamoylating species contribute to antitumor activity by inhibiting O6-alkylguanine transferase, an enzyme involved with DNA repair. It was studied in the treatment of several types of cancer, however, its development was discontinued.

L-778123 is a dual inhibitor of Farnesyl Protein Transferase (FPTase) and Geranylgeranyl Protein Transferase type-I (GGPTase-I), which can completely inhibit Ki-Ras prenylation. L-778123 has been used in phase I clinical trials to determine its effectiveness in treating patients with recurrent or refractory solid tumors. L-778123 was also studied in combination with paclitaxel to determine efficacy as a treatment for both recurrent or refractory solid tumors, and lymphomas.

Omaciclovir (previously known as H2G), a cyclic guanosine analog that is structurally similar to acyclovir and was in clinical development for the treatment of herpesvirus infections. This drug acted against varicella-zoster virus (VZV), by the formation of high concentrations of relatively stable H2G-triphosphate, which is a potent inhibitor of the viral DNA polymerases. However, further development of this drug was discontinued.

Enzastaurin is a serine/threonine kinase inhibitor that showed antiangiogenic, antiproliferative, and proapoptotic properties in vitro and antitumor activity in vivo in a xenograft Waldenström macroglobulinemia (WM) model. Enzastaurin (LY317615) is a potent PKCβ selective inhibitor. Enzastaurin suppresses angiogenesis and was advanced for clinical development based upon this antiangiogenic activity. Enzastaurin suppresses tumor growth through multiple mechanisms: direct suppression of tumor cell proliferation and the induction of tumor cell death coupled to the indirect effect of suppressing tumor-induced angiogenesis. Enzastaurin is an orally administered drug that was intended for the treatment of solid and haematological cancers. Enzastaurin had shown encouraging preclinical results for the prevention of angiogenesis, inhibition of proliferation and induction of apoptosis as well as showing limited cytotoxicity within phase I clinical trials. However, during its assessment in phase II and III clinical trials the efficacy of enzastaurin was poor both in combination with other drugs and as a single agent. Eli Lilly discontinued development of enzastaurin after top-line data from the double-blind, international Phase III PRELUDE trial in 758 DLBCL patients showed that enzastaurin missed the primary endpoint of improving DFS vs. placebo.

LADOSTIGIL, a rasagiline derivative, is a reversible acetylcholinesterase and butyrylcholinesterase inhibitor with neuroprotective properties. It also acts as an irreversible brain monoamine oxidases inhibitor. It is under development for the treatment of neurodegenerative disorders like dementia and Alzheimer's disease.

Afeletecan (Bay 38-3441) is a camptothecin glycoconjugate which stabilizes the active lactone form of camptothecin and allows selective uptake into tumor cells. Afeletecan is a topoisomerase inhibitor. Afeletecan was in phase I clinical trials with Bayer for the treatment of cancer; however, development appears to have been discontinued.

Quiflapon Sodium (MK-0591; (3-[1-(4-chlorobenzyl)-3-(t-butylthio)-5-(quinolin-2-yl-methoxy)- indol-2-yl]-2,2-dimethyl propanoic acid, previously L-686,708) had been in phase II clinical studies for the treatment of inflammatory bowel disease, but the study was discontinued later, because in spite of MK-591 markedly inhibited Leukotrienes (LT) biosynthesis, it did not differ significantly from placebo in clinical efficacy. Also was discovered, that MK-0591 may modify the airway changes associated with bronchial hyper responsiveness, as well as offer symptomatic relief in asthma. MK-0591 is a selective and specific 5-Lipoxygenase-activating protein (FLAP) inhibitor with an IC50 value of 1.6 nM in a FLAP binding assay. In additional, recently was discovered, that MK591 possesses all major attributes of a standard anti-metastatic agent with significant cancer-selective effect, and suggest that MK591 may turn out to be an effective agent for therapy of castration-resistant, bone-metastatic prostate cancer. Though details of the molecular underpinnings of the anti-metastatic action of MK591 are unknown at this time, this finding gives an opportunity for further exploration to better understand the signaling mechanisms involved by in vitro and in vivo experiments.

Icopezil (previously known as CP-118,954) was developed as a selective acetylcholinesterase inhibitor for the treatment of cognitive disorders. Phase II trials of icopezil were underway in Japan and in the USA for the treatment of patients with Alzheimer's disease. However, Pfizer has discontinued these studies.