Nisoxetine, 3-(o-methoxyphenoxy)-3-phenyl-N-methyl-propyl-amine, is a most active and selective inhibitor of norepinephrine uptake, which was developed by Eli Lilly as an antidepressant drug. It was shown that nisoxetine dose-dependently reduced acute food intake and the additive effect of it was preserved in obese mice. In addition, was revealed that nisoxetine produced local but not systemic analgesia against cutaneous nociceptive stimuli in rodents. However, this drug has no clinical applications in humans.

Mobecarb is morpholineacetic acid derivative patented by Carlo Erba Societa per Azioni to prevent vascular rupture among persons afflicted with arterial hypertension. In preclinical models Mobecarb shows the capillary protective activity in partially omentectomized rats.

Norlevorphanol is the levo-isomer of 3-hydroxymorphinan (morphinan-3-ol). It is is an opioid analgesic of the morphinan family. Norlevorphanol is a Schedule I controlled substance (opiate).

Upidosin [REC 152739, REC 22009] is an α1-blocker that was in phase II trials with Recordati in Belgium and Israel for the treatment of benign prostatic hyperplasia. When evaluated in radioligand binding assays with expressed animal or human alpha-1 ARs, Upidosin shows marked to moderate selectivity for the alpha-1a AR subtype. Its affinity for the recombinant alpha-2 AR subtypes or native dopaminergic D2 receptor was about 100-fold lower than that for alpha-1a AR subtype.

NT-702 (parogrelil hydrochloride) is a novel phosphodiesterase 3 (PDE) inhibitor, and being developed for the treatment of intermittent claudication (IC) in patients with peripheral arterial disease. In Japan, Phase 2 studies are being conducted for intermittent claudication caused by arteriosclerosis obliterans, intermittent claudication caused by spinal canal stenosis, and asthma. In the USA, a Phase 2 study for intermittent claudication caused by arteriosclerosis obliterans has been successfully completed. Also was shown, that NT-702 has an anti-inflammatory effect as well as a bronchodilating effect and might be useful as a novel potent therapeutic agent with both a bronchodilating and an anti-inflammatory effect.

Varespladib (LY315920; A-001) is a potent and selective inhibitor of IIa, V, and X isoforms of human non-pancreatic secretory phospholipase A2 with nM IC50. The molecule acts as an anti-inflammatory agent by disrupting the first step of the arachidonic acid pathway of inflammation. Varespladib methyl is being developed by Anthera Pharmaceuticals Inc for the potential treatment of coronary artery disease, acute coronary syndrome and inflammation. Varespladib methyl is a prodrug that is rapidly metabolized to varespladib, and both compounds are able to potently inhibit the enzymes of the human secretory phospholipase groups. Phase II clinical trials of varespladib methyl in patients with coronary artery disease, rheumatoid arthritis, asthma and ulcerative colitis revealed that the drug was well tolerated. Varespladib methyl did not demonstrate a good efficacy profile in patients with rheumatoid arthritis, asthma and ulcerative colitis; whereas in patients with coronary artery disease, varespladib methyl consistently reduced LDL-cholesterol levels, (elevated LDL-cholesterol levels are a marker of increased cardiovascular risk). Varespladib methyl could represent a novel therapy for the treatment of cardiovascular disease, although the efficacy, safety profile and advantages of this drug compared with existing therapeutic options would need to be established in upcoming phase III trials.

Semapimod (CNI-1493) is a cytokine inhibitor and synthetic guanylhydrazone mitogen-activated protein kinase blocker, is being developed by Cytokine PharmaSciences as a potential treatment for Crohn's disease and other inflammatory conditions. As of December 2001, a phase I study demonstrating the safety of the compound had been completed and phase II trials for psoriasis and Crohn's disease were ongoing. In April 2003, preclinical and early clinical studies were underway for a variety of indications, including congestive heart failure and pancreatitis. Semapimod inhibits activation of p38 MAPK and NF-κB and induction of cyclooxygenase-2 by TLR ligands, but not by IL-1β or stresses. Semapimod inhibits TLR4 signaling (IC50 ≈0.3 umol) and acts by desensitizing cells to LPS; it fails to block responses to LPS concentrations of ≥5 ug/ml. Semapimod had been in phase II clinical trials by Ferring Pharmaceuticals for the treatment of Crohn's disease. However, this research has been discontinued. Semapimod is in phase I clinical trials for the treatment of autoimmune disorders and inflammation.

Proadifen is an inhibitor of drug metabolism and cytochrome P450 enzyme system activity. It stimulated the release of prostacyclin (PGI2) from the rabbit aorta, bovine aorta and human umbilical vein in vitro, but had no effect on cultured smooth muscle from the bovine aortic media. In human platelets, proadifen inhibited prostaglandin and thromboxane production induced by A23187, thrombin, and ADP. Proadifen might thus constitute the prototype of a new class of antiplatelet drugs.

Brequinar is a synthetic quinolinecarboxylic acid analogue with antineoplastic properties. Brequinar inhibits the enzyme dihydroorotate dehydrogenase, thereby blocking de novo pyrimidine biosynthesis. This agent may also enhance the in vivo antitumor effect of antineoplastic agents such as 5-FU. Brequinar had been in phase II clinical trials by Bristol-Myers Squibb for the treatment of cancer and transplant rejection. However, this research has been discontinued. Brequinar had been also in preclinical studys for the treatment of cytomegalovirus infections. However, this research has been discontinued.

Piboserod (SB 207266) is a selective 5-HT(4) receptor, antagonist. The 5-HT4 receptor antagonists are thought to antagonize both the ability of serotonin to sensitize the peristaltic reflex and 5-HT-induced defecation, at least in animal studies. As 5-HT4 receptors are present in human atrial cells and when stimulated may cause atrial arrhythmias, piboserod was under investigation in clinical trials for atrial fibrillation. In addition, GlaxoSmithKline studied the drug for the management of irritable bowel syndrome. Nevertheless, development both indications had been discontinued. Piboserod has successfully passed phase II clinical trials for the treatment of patients with congestive heart failure.