Otamixaban is a synthetically derived parenteral fXa inhibitor currently in late stage clinical development at Sanofi-Aventis for the management of acute coronary syndrome. Otamixaban is a potent (Ki = 0.5 nM), selective, rapid acting, competitive and reversible fXa inhibitor that effectively inhibits both free and prothrombinase-bound fXa. Factor Xa (fXa) is a critical serine protease situated at the confluence of the intrinsic and extrinsic pathways of the blood coagulation cascade. FXa catalyzes the conversion of prothrombin to thrombin via the prothrombinase complex. Its singular role in thrombin generation, coupled with its potentiating effects on clot formation render it an attractive target for therapeutic intervention. In vivo experiments have demonstrated that Otamixaban is highly efficacious in rodent, canine and porcine models of thrombosis. In addition, recent clinical findings indicate that Otamixaban is efficacious, safe and well tolerated in humans and therefore has considerable potential for the treatment of acute coronary syndrome. Following the results of the Treatment of non-ST elevation Acute coronary syndrome with otamixaban, Sanofi has decided to discontinue the investigational programme with otamixaban, due to efficacy lower than expected. Otamixaban did not show superior benefit/risk to the combination of unfractionated heparin.

Nitroarginine (LNNA), an analog of L-arginine, is a competitive inhibitor of nitric oxide synthase which has been shown to prevent glutamate toxicity. Nitroarginine has been experimentally tested for its ability to prevent ammonia toxicity and ammonia-induced alterations in brain energy and ammonia metabolites. The Kd value (k(off)/k(on)) of bovine brain cNOS for LNNA was 15 nM. In contrast to the potent and slow onset of LNNA inhibition of brain cNOS, LNNA inhibition of inducible mouse macrophage NOS (iNOS) was weaker (Ki = 4.4 uM) and rapidly reversible. Thus, LNNA was a 300-fold more potent inhibitor of bovine brain cNOS than mouse macrophage iNOS. By inhibiting nitric oxide synthase LNNA causes the selective reduction of blood flow to tumor cells. Despite the potential of LNNA to function as an adjuvant in cancer therapies, its poor solubility and stability have hindered the development of an injectable formulation of LNNA that is suitable for human administration.

Galdansetron is a selective serotonin antagonist compound that is effective against vomiting and nausea. This type of drug is used to treat motion sickness or side effects of chemotherapy or anesthetics.

Anilopam is an opioid analgesic of the benzazepine class. It is an opioid receptor agonist.

Coumazoline is a vasoconstrictor developed as a nasal decongestant by a French corporation Labez. Intravenous administration of the compound to dogs lead to a marked and prolonged drop in the temperature of the gingival mucosa. In rats, coumazoline caused slowing of the dye diffusion on the surface of the skin. The compound did not influence the ciliary motility, as was measured on an isolated guinea pig trachea.

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.

UT-231B is an iminosugar that was under development by United Therapeutics Corporation as an oral drug for the treatment of hepatitis C virus (HCV). UT-231B completed acute and chronic Phase I dosing studies in early 2003. A Phase II proof-of-concept study for UT-231B in patients infected with hepatitis C who have failed conventional therapies was started, but the development of drug seemed to be discontinued.

Pimilprost (SM-10902) and its free acid, SM-10906 are new stable 3-oxa-methano prostaglandin (PG) I1 analogs, SM-10902 is a prodrug of SM-10906. SM-10906, but not SM-10902 was demonstrated to be an agonist for IP receptors. SM-10906 was shown to exert its anti-platelet and vasodilatory activities through the increase of the cAMP level. Pimilprost was being developed by Dainippon Sumitomo Pharma (formerly Sumitomo Pharmaceuticals) in Japan for the treatment of skin ulcers. In Japan, an NDA was filed for pimilprost and was awaiting registration. However, development appears to have been discontinued.

Etorphine was the first potent opiate agonist employed primarily for use in non-domestic and wild species. Etorphine was 500 times as potent as morphine, with a very rapid onset and short duration of action. In morphine-dependent subjects, etorphine suppressed abstinence but for a shorter period than morphine. Etorphine is a full opiate agonist and binds to multiple opiate sites in the central nervous system. It is believed to produce its clinical effects through binding the µ-, δ-, and κ- opiate sites. It has a potent effect on depressing the respiratory centers of the CNS thus resulting in apnea being commonly seen in immobilized animals. Etorphine revolutionized the ability of biologists and veterinarians to safely capture and restrain many species that previously could not be handled. Etorphine is not currently commercially available due to lack of production by the manufacturer.

Berupipam (also known as NNC 22-0010), a dopamine antagonist with a high affinity and selectivity for D1 receptor has been studied for patients with psychotic disorders. Berupipam participated in phase I clinical trials; however, further development of this drug was discontinued