Atopaxar, also known as E 5555 is a novel reversible protease-activated receptor-1 (PAR-1) thrombin receptor antagonist. The inhibition of thrombin-mediated platelet activation by means of protease-activated receptor-1 inhibitors represents an attractive therapeutic option for patients with atherothrombotic disease processes. In preclinical studies, atopaxar demonstrated inhibition of thrombin receptor-activating peptides (TRAP)- and thrombin-induced platelet aggregation. Atopaxar was being developed by Eisai for acute coronary syndromes (ACS) and coronary disorders, including atherothrombosis, unstable angina pectoris and myocardial infarction. Atopaxar was in phase II clinical development in the US, EU and Japan. However, development was discontinued in May 2012.

Oxadimedine, an antihistamine that was developed as a local anesthetic. Information about the current use of this compound is not available.

Arctigenin is a plant lignan extracted from Arctium lappa that has been shown to have estrogenic properties. In ER-positive MCF-7 cells, arctigenin efficiently inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced cell migration and invasion. Arctigenin confers anti-metastatic effects by inhibiting MMP-9 and uPA via the Akt, NF-κB and MAPK signaling pathways on breast cancer, regardless of ER expression. Intake of arctigenin could be an effective supplement for breast cancer patients. Arctigenin is a phenylpropanoid dibenzylbutyrolactone lignan compound possessing antitumor, anti-inflammatory, anti-influenza, antioxidant, antibacterial, and hypoglycaemic activities. Arctigenin exhibited significant antiproliferative activity against CCRF-CEM cells after 72 h treatment with IC50 values of 1.21 ± 0.15 um. It arrested CCRF-CEM cells in the S phase. It induced apoptosis in CCRF-CEM cells in a concentration- and time-dependent manner. Arctigenin is a good candidate for the development of novel agents against T-cell lymphoma. Arctigenin has been found to act as an agonist of adiponectin receptor 1 (AdipoR1). Arctigenin is an antagonist of MR and effectively decreases the Na/K-ATPase 1 gene expression, thus highlighting its potential as an anti-hypertensive drug lead compound.

Tropanserin (MDL 72422) is a potent and selective 5-HT3 receptor antagonist. It was investigated as a drug for the treatment of migraine. MDL 72222 was shown to be an effective antimigraine agent in a double-blind placebo-controlled study.

Menarini was developing ibodutant (also known as MEN15596) as a selective neurokinin (NK) 2 and tachykinin receptor antagonist. It is known that tachykinins have been implicated in the pathophysiology of irritable bowel syndrome (IBS) with diarrhoea. Ibodutant was studied as a treatment for gastrointestinal disorders. A phase 2 trial completed in May 2012 with positive results. Ibodutant participated in a 52-week phase 3 in women with IBS with diarrhea, however, the study was terminated because of the negative results of the sister study NAK-06 and the low overall response rate at week 24.

Sipatrigine (BW 619C89), a blocker of neuronal Na+ and Ca2+ channels, has neuroprotective efficacy. This drug was in phase II studies in stroke patients who received iv infusions of sipatrigine. The main adverse events observed were hallucinations and vomiting. The Phase II trial was terminated when Glaxo merged with Wellcome and a decision was made to develop the NMDA (glycine site) receptor antagonist gavestinel (from Glaxo), which showed no efficacy in a randomized, double blind, placebo- controlled trial. It was also assumed, that sipatrigine could have therapeutic potential for major depression and bipolar depression through antagonism of the two-pore-domain K+ channel TREK-1. but further evaluation of its antidepressant therapeutic and toxic effects in animal models is needed before clinical application.

Tozadenant (SYN115) is an adenosine A2A receptor antagonist initially developed for treatment of Parkinson's disease but may also have utility in other CNS disorders. A2a receptors are expressed in high concentration in the striatum of the brain and play an important role in regulating motor function. Tozadenant blocks the effect of endogenous adenosine at the A2a receptors, resulting in the potentiation of the effect of dopamine at the D2 receptor and inhibition of the effect of glutamate at the mGluR5 receptor. This enables restoration of motor function in Parkinson’s disease. Tozadenant has the potential for use as mono-therapy or adjunctive therapy in combination with L-Dopa and dopamine agonists for the treatment of the motor and non-motor symptoms associated with Parkinson’s disease. may also have neuroprotective effects, which raises the possibility that it could slow the deterioration of dopamine producing cells and modify disease progression. As was reported in international, multicentre, phase 2b, randomised, double-blind, placebo-controlled, parallel-group, dose-finding clinical trial of tozadenant in levodopa-treated patients with Parkinson's disease who had motor fluctuations tozadenant at 120 or 180 mg twice daily was generally well tolerated and was effective at reducing off-time.

Intepirdine, also known as SB-742457, RVT-101, was originally developed by GlaxoSmithKline (GSK) as an antagonist of the serotonin receptor 6 (5-HT6). GSK sold the rights for further study of this drug to Axovant Sciences in 2014. Intepirdine is in phase 3 clinical trial for Alzheimer's and in a phase 2 trial for dementia with Lewy bodies.

Eucatropine is known as an anticholinergic agent, which acts as antagonist of muscarinic cholinergic receptors.