Avasimibe (CI 1011) is a potent ACAT (Acyl-CoA:cholesterol acyltransferase) inhibitor. Avasimibe inhibits both ACAT1 and ACAT2 isoforms. Avasimibe was in development by Parke-Davis (now Pfizer) in the US for the treatment of atherosclerosis and hyperlipidaemia. Avasimibe was in phase III studies and more than 1300 patients had been treated for up to one year, however, in October 2003, Pfizer announced that development had been discontinued.

LY2606368 (Prexasertib) is a small-molecule Chk-1 inhibitors invented by Array and being developed by Eli Lilly and Company. Lilly is responsible for all clinical development and commercialization activities. LY2606368 is advancing in Phase 2 clinical trials for cancer. Prexasertib preferentially binds to and inhibits CHK1 and, to a lesser extent, inhibits CHK2. Chk-1 is a protein kinase that regulates the tumor cell's response to DNA damage often caused by treatment with chemotherapy. In response to DNA damage, Chk-1 blocks cell cycle progression in order to allow for repair of damaged DNA, thereby limiting the efficacy of chemotherapeutic agents. Inhibiting Chk-1 in combination with chemotherapy can enhance tumor cell death by preventing these cells from recovering from DNA damage.

HM-30181 is a highly selective and potent inhibitor of Multi-drug resistance 1 (MDR1, ABCB1), also known as P-glycoprotein (P-gp). Co-administration of HM30181 greatly increased oral bioavailability of tubulin-stabilizing chemotherapeutic agent paclitaxel. Oraxol is an oral dosage form of paclitaxel administered orally with the HM30181A molecule. Oraxol offers patients with paclitaxel-responsive tumors the possibility of oral therapy without the requirement for premedication to prevent infusion-related hypersensitivity-type reactions. Current clinical data suggests the promising potential of a better clinical response and tolerability profile, which can likely to be attributed to the better pharmacokinetic profile achieved. Oraxol is presently in a Phase 3 trial in metastatic breast cancer and poised to enter into a combination study for treatment of advanced gastric cancer with ramucirumab through a clinical trial collaboration with Eli Lilly and Company.

Almorexant (ACT-078573) is an orally active dual orexin receptor antagonist that is being developed by Actelion Ltd, in collaboration with GlaxoSmithKline plc, for the treatment of primary insomnia. Almorexant is a first-in-class compound that targets the orexin system, which plays a key role in wake promotion and stabilization; In January 2011, GlaxoSmithKline (GSK) and Actelion Ltd announced that clinical development of Phase III of almorexant has been discontinued. This decision follows a review of data from additional clinical studies, which were conducted to further establish the clinical profile of almorexant, including the tolerability profile.

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.

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.

Ritanserin (INN, USAN, BAN) is a serotonin receptor antagonist which was never marketed for clinical use but has been used in scientific research. In humans, ritanserin increases deep slow-wave sleep, improved liveliness in a variety of psychiatric disorders and facilitated participation in behaviour therapy. During clinical trials, unexpected observations indicated that ritanserin may be of value in treating obsessive-compulsive disorder, acute mania, negative symptoms of schizophrenia, drug addicts, etc. Clinical observations confirmed the efficacy of ritanserin in the chronic withdrawal phase after detoxification from ethanol. Ritanserin had been in phase III clinical trials by Janssen L.P. for the treatment of anxiety disorder and major depressive disorder. However, the clinical development of ritanserin was discontinued.

Encenicline (EVP-6124; MT-4666) acts as a potent partial and selective agonist at alpha-7 nicotinic acetylcholine receptor. Encenicline significantly improved memory function in animal models. FORUM Pharmaceuticals (formerly EnVivo Pharmaceuticals) is developing encenicline for the treatment of cognition disorders such as schizophrenia and for Alzheimer's disease.

Acifran (AY-25,712), an uncommercialized Ayerst compound exerting lipid-lowering activity in vivo, has been shown to also elicit similar effects as niacin in preliminary clinical testing and has been shown to bind to both high affinity (HM74A; GPR109A) and low affinity (HM74; GPR109B) niacin receptors. The EC50 values of the separated acifran enantiomers for the GPR109a and 109b receptors showed that, as with acifran itself, the (+)-enantiomers were essentially twice as active as the racemic mixtures, whereas the activity of the (-)-enantiomers was more variable and highly dependent on purity. S-enantiomer of acifran is the active principle. All of the activity of racemic acifran could be attributed to the (S)-enantiomer, and hence, from this precedent, (+)-enantiomers would be assigned to the S-configuration. However, the absolute configuration was not confirmed experimentally.

Idazoxan is an alpha2 receptor antagonist which also shows activity at imidazoline I1 and I2 receptors and modulates the release of dopamine. Idazoxan was in phase II development in the US. Later the development of idazoxan for schizophrenia was discontinued. It was also in clinical trials for cognition disorders in United Kingdom, and was also discontinued. Idazoxan is used in scientific research as a tool for the study of alpha 2-adrenoceptors.