Indantadol (previously known as CHF-3381) is an oral and noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist and reversible monoamine oxidase-A (MAO-A) inhibitor that is being developed by Vernalis plc, under license from Chiesi Farmaceutici SpA, for the potential treatment of neuropathic pain. In preclinical studies, indantadol exhibited neuroprotective effects after kainate-induced seizures and displayed anticonvulsant and antihyperalgesic activity. Indantadol also caused a dose-dependent decrease in exploratory motility. In a human heat-capsaicin-induced pain model, indantadol at a dose of 500 mg effectively reduced the area of secondary hyperalgesia. The tolerability profile of the drug at single doses up to 600 mg and twice-daily doses up to 400 mg in clinical trials was significantly more favorable than for other NMDA antagonists. Most side effects have been observed to be mild, and include dizziness and asthenia. Indantadol was in phase II clinical trials for the treatment of chronic cough and neuropathic pain. However, these studies had been discontinued.

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.

Tifluadom is an opioid benzodiazepine with potent analgesic activity. Studies using antagonists for κ-, δ-, and μ-opiate receptors in guinea pig myenteric plexus-longitudinal muscle preparation and mouse and rabbit vasa deferentia showed that Tifluadom is an opioid analgesic with a preference for opiate κ-receptors. In rat brain homogenates, tifluadom displaced kappa-antagonist naloxone from its binding sites with an IC50 of 12nM but had no effect on flunitrazepam binding. Tifluadom produced a dose-related diuresis in normally hydrated rats and the diuretic effect was antagonized by naloxone and blocked by morphine administration.

Linifanib (ABT-869) is a structurally novel, receptor tyrosine kinase (RTK) inhibitor that is a potent inhibitor of members of the vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF) receptor families, but has much less activity against unrelated RTKs, soluble tyrosine kinases, or serine/threonine kinases. Linifanib (ABT-869) does not have a general antiproliferative effect due to its high dose requirement. However, it may exhibit potent antiproliferative and apoptotic effects on tumor cells whose proliferation is dependent on mutant kinases, such as FMS-related tyrosine kinase receptor-3 (FLT3). Linifanib (ABT-869) was in phase III clinical trial for the treatment of hepatocellular carcinoma, but the study failed to meet the primary end point.

Adrogolide is a chemically stable prodrug of the dopamine D1 receptor agonist A-86929. Adrogolide is rapidly converted in plasma to A-86929. A-86929 has high affinity and functional selectivity for the dopamine D1 receptor. Adrogolide has been in phase II clinical trials for the treatment of Parkinson's disease and cocaine abuse. However, this research has been discontinued. The adverse events associated with its use of adrogolide were of mild-to-moderate severity and included injection site reaction, asthenia, headache, nausea, vomiting, postural hypotension, vasodilitation, and dizziness.