MK-0893, developed by Merck, is a reversible and competitive antagonist with high binding affinity (IC(50) of 6.6 nM) and functional cAMP activity (IC(50) of 15.7 nM). MK-0893 reached Phase 2; 12 weeks of once daily oral dosing led to significant and dose-dependent reductions in fasting and post-prandial plasma glucose and in HbA1c, with similar low incidences of hypoglycaemia as a metformin cohort. Combinations with metformin and sitagliptin were also trialled, and risk for hypoglycaemia was assessed in healthy males which showed the drug caused lengthening of recovery times. However, plasma levels of LDL cholesterol and liver transaminases were increased in some studies, as was body weight and blood pressure, all of which were not evident pre-clinically, and MK-0893 was discontinued.

Amiprilose hydrochloride (brand name Therafectin), a novel synthetic carbohydrate with anti-inflammatory properties, which was developed for the treatment of rheumatoid arthritis. In September 1993, FDA informed that this drug could not be approved because there was not adequate data demonstrating the drug’s effectiveness.

Trovirdine [LY 300046, LY 300082, PETT 1] is a NNRT inhibitor of HIV-1 RT, which progressed through Phase II trials for the treatment of HIV infection. Trovirdine inhibits HIV-1 RT with an IC50 of 7 nM. Cell culture experiments demonstrated that LY300046 was a potent inhibitor of the replication of HIV-1 in human T-cell lines and human PBL, including spread of the virus from infected to uninfected T cells. It was potent against patient isolates as well as laboratory isolates of HIV-1 but was not active against HIV-2 or simian immunodeficiency virus.

Picobenzide is a synthetic product which is of therapeutic interest owing to its neuroleptic, anti-inflammatory and spasmolytic action and because its properties are similar to those of the phenotiazines. The product is largely metabolized into the N-oxide form and is also partially eliminated in urine in an unaltered state.

Boehringer Ingelheim is developing BI-671800, an orally administered treatment for seasonal allergic rhinitis and asthma. BI-671800 is an antagonist of the PGD2 receptor, CRTH2. PGD2 stimulates bronchoconstriction and allergic airway inflammation in animal models. Inhibition of CRTH2 may reduce airway inflammatory cells, IL -4, -5, -13 production, serum IgE and airway hyper reactivity. Treatment with BI-671800 in poorly controlled asthmatic patients receiving FP was associated with a significant improvement in FEV1. BI-671800 was well tolerated at a total daily dose of 800 mg for 6 weeks.

Indopanolol is indole derivative patented by German pharmaceutical company Sandoz-Patent-G.m.b.H. as α- and β-adrenergic receptor blocking agent.

Flunamine is an antiparkinsonian agent.

Fosarilate was studied as an antiviral agent. Information about the current use of this compound is not available.

ISAMFAZONE is a non-steroidal antiinflammatory, analgesic agent.

Homocysteine, an amino acid synthesized intracellularly by removal of the N-methyl group from the essential amino acid methionine. High plasma level of homocysteine is called hyperhomocysteinemia is a clinical biomarker for increased risk of cardiovascular disease, thromboembolic diseases, and myocardial infarction. It was shown, that hyperhomocysteinemia could be an independent risk factor for dementia and Alzheimer's disease. The falling of homocysteine concentrations in response to increasing B-group-vitamin status, have the hope that mental decline, or Alzheimer's disease, could be prevented by dietary modification or food fortification. Besides, homocysteine can behave as an anti-oxidant agent by increasing the antioxidant capacity of the tumor and endothelial cells.