Traxoprodil (CP-101,606) is a potent, selective N-Methyl-D-aspartate (NMDA) receptor (NR2B subunit) antagonist under development by Pfizer for its potential as a neuroprotectant in head injury and neurodegenerative disease. It is in phase II trials in the US and in phase I in Japan for the potential treatment of head injury, such as, Depressive Disorder, Major and Parkinson's Disease. CP-101,606 does not protect against glutamate-induced neurotoxicity in cultured cerebellar neurons, up to a dose of 10 uM. These results are consistent with CP-101,606 being a potent NMDA antagonist, selective for the type of NMDA receptor associated with the hippocampus. Some further investigation revealed that CP-101,606 was associated with a dose-related dissociation and amnesia. These results support the hypothesis that glutamate antagonists may be useful antidyskinetic agents. However, future studies will have to determine if the benefits of dyskinesia suppression can be achieved without adverse cognitive effects.

Tozasertib, originally developed as VX-680 by Vertex (Cambridge, MA) and later renamed MK-0457 by Merck (Whitehouse Station, NY), was the first aurora kinase inhibitor to be tested in clinical trials. The drug, a pyrimidine derivative, has affinity for all aurora family members at nanomolar concentrations with inhibitory constant values (Ki(app)) of 0.6, 18, and 4.6 nM for aurora A, aurora B, and aurora C, respectively. Preclinical studies confirmed that tozasertib inhibited both aurora A and aurora B kinase activity, and activity has been reported against prostate, thyroid, ovarian, and oral squamous cancer cell lines. Upon treatment with tozasertib, cells accumulate with a 4N DNA content due to a failure of cytokinesis. This ultimately leads to apoptosis, preferentially in cells with a compromised p53 function. Tozasertib is an anticancer chemotherapeutic pan-aurora kinase (AurK) inhibitor that also inhibits FMS-like tyrosine kinase 3 (FLT3) and Abl. Tozasertib is currently in clinical trials as a potential treatment for acute lymphoblastic leukemia (ALL). In cellular models of cancer, tozasertib activates caspase-3 and PARP and decreases expression of HDAC, increasing apoptosis and inhibiting cell growth. In other cellular models, tozasertib inhibits cell proliferation and metastasis by blocking downstream ERK signaling and downregulating cdc25c and cyclin B. This compound also decreases tumor growth in an in vivo model of prostate cancer.

Tofetridine is an analgesic agent.

Tesmilifene is a small-molecule antineoplastic drug and chemopotentiator that was under development by YM BioSciences for the treatment of breast cancer. Tesmilifene was developed as a selective ligand of the antiestrogen binding sites without estrogen receptor affinity. Tesmilifene potentiates the cytotoxicity of a variety of chemotherapy drugs in vitro and in vivo. Tesmilifene in combination with doxorubicin provides an unexpected and very large survival advantage over doxorubicin alone in a randomized trial in phase III clinical trial in advanced breast cancer. Unfortunately, Tesmilifene application associated with high rate disease and treatment-related adverse events and poor quality of life. Based on these results further development of Tesmilifene was discontinued

Selprazine was developed as a sedative agent for inhibition of aggression. Information about the current use of this compound is not available.

Saterinone, a dual-action drug combines both alpha-1 blocking vasodilatory property and phosphodiesterase III (PDE III) inhibition--mediated inotropism. PDE III inhibitors are well established in the acute intravenous treatment of patients with decompensated chronic congestive heart failure. Saterinone was demonstrated to be a safe and potent drug on short-term application without major changes in myocardial oxygen consumption. Saterinone was studied in phase II trials in Germany for the treatment of heart failure. However, the development of this drug has been discontinued.

Naftypramide is a nonsteroidal anti-inflammatory drug. It was used in the treatment of gynecological inflammatory diseases.

Mitonafide is a nitro-containing antitumor drug. Mitonafide participated in clinical trials phase II in colorectal cancer patients, however, the results have shown that the drug was not active and induced severe myelotoxicity. Besides, the drug was involved in phase II for the patients with non-small cell lung cancer (NSCLC), where it was not active in spite of the safe administration. Information about the current development of this drug is not available.

Metitepine, a psychotropic agent was developed as a non-selective antagonist of serotonin, dopamine, and adrenergic receptors. Metitepine has never been marketed.

Aranotin, a metabolite of Arachniotus aureus, possesses the antiviral and antibiotic properties. It inhibits viral RNA synthesis against strains of rhino-, coxsackie, polio- and parainfluenza viruses.