AZD9164 was invented by AstraZeneca as a muscarinic M(3) receptor antagonist for evaluation of the potential as a treatment for chronic obstructive pulmonary disease. However, in 2010 studies were discontinued.

Olmidine (also known as dl-mandelamidine) is an antihypertensive drug that has never been marketed. Information about the current use of this drug is not available.

Fosmenic acid was used for the treatment of atherosclerosis. Information about the current use of this drug is not available.

Quinotolast (also known as FK021) is an orally active mast cell stabilizer which has a cytoprotective effect on the gastric mucosa. Quinotolast was patented in 1985 by Japanese pharmaceutical company Fujisawa Pharmaceutical Co., Ltd. as an antiallergic and antiulcer agent. In preclinical models, Quinotolast potently inhibited such type I allergic reactions as passive cutaneous anaphylaxis (PCA) and anaphylactic bronchoconstriction in rats by both intravenous and oral dosing. Quinotolast inhibited histamine release from rat peritoneal cells, but it had no antagonistic effect on histamine-, serotonin-, platelet activating factor- or bradykinin-induced cutaneous reactions in rats. Moreover, it was clearly demonstrated that quinotolast and DSCG had a cross tachyphylaxis to inhibit PCA in rats, suggesting that these drugs, at least in part, share the same mechanism of action. Quinotolast caused a significant increase in the mucociliary transport rate in quails. Quinotolast significantly depressed the cough reflex induced by citric acid in normal and bronchitic guinea pigs.

Meletimide (R 5183) is a powerful anticholinergic agent with pronounced peripheral and central action.

Deferitazole is an iron chelator, developed by the FerroKin BioSciences (later acquired by Shire, and then by Takeda). Deferitazole is a member of the desazadesferrithiocin class of siderophore-related tridentate chelators. It binds Fe(III) with very high affinity and selectivity over Fe(II) and other biologically important metals. Deferitazole was investigated in phase 2 clinical trials in patients with iron overload due to repeated red blood cell transfusion and beta-thalassemia, however, the development of the drug was discontinued. In preclinical models, deferitazole demonstrated efficacy for the treatment and prevention of malaria.

Deferitazole is an iron chelator, developed by the FerroKin BioSciences (later acquired by Shire, and then by Takeda). Deferitazole is a member of the desazadesferrithiocin class of siderophore-related tridentate chelators. It binds Fe(III) with very high affinity and selectivity over Fe(II) and other biologically important metals. Deferitazole was investigated in phase 2 clinical trials in patients with iron overload due to repeated red blood cell transfusion and beta-thalassemia, however, the development of the drug was discontinued. In preclinical models, deferitazole demonstrated efficacy for the treatment and prevention of malaria.

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.

Prisotinol is aminoalkyl-5-pyridinol patented by Ciba-Geigy A.-G. for treatment of angina pectoris. Prisotinol was studied in phase II clinical trials as a cardioprotective agent.