Cevipabulin is a synthetic, water-soluble tubulin-binding agent with potential antineoplastic activity. Cevipabulin appears to bind at the vinca-binding site on tubulin but seems to act more similar to taxane-site binding agents in that it enhances tubulin polymerization and does not induce tubulin depolymerization. The disruption in microtubule dynamics may eventually inhibit cell division and reduce cellular growth.

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.

Juvantia Pharma and Orion developed ORM-12741, also known as ORM-10921, a novel selective antagonist of alpha-2C adrenoceptors for the treatment of depression and Alzheimer's disease. ORM-12741 participated in phase II clinical trial where was evaluated the safety and efficacy of the drug in patients with Alzheimer's disease. In spite of the successfully completed phase II, further study of the drug for this disease was discontinued. In addition, ORM-12741 participated in clinical trial phase II to prove the concept that this drug could prevent blood vessel spasms for Raynaud's phenomenon. Raynaud's phenomenon is a disorder of the digital blood vessels resulting in episodic impairment of blood flow. However, this study was terminated because of the recommendation by study Data and Safety Monitoring Committee to the sponsor following the interim analysis of 8 subjects.

Elzasonan (CP 448187) is a serotonin 1B/1D receptor antagonist. Elzasonan was primarily metabolized via oxidative N‐demethylation, N‐oxidation, and aryl hydroxylation. Pfizer was developing elzasonan for the treatment of anxiety and affective disorders however development has been discontinued.

Vercirnon (GSK-1605786, CCX-282, nTraficet-EN) is a selective, and potent antagonist of human CCR9. Vercirnon binds to the intracellular side of the receptor, exerting allosteric antagonism and preventing G-protein coupling. CCR9 is a tissue-specific lymphocyte trafficking molecule that selectively attracts both B- and T-cells to the small gut. Inhibition of CCR9 by GSK-1605786 may inhibit B- and T-cell entry to the small gut and ameliorate inflammation while leaving immune function at other anatomical sites unaffected. Vercirnon is an orally bioavailable, anti-inflammatory agent that is being developed by ChemoCentryx for treatment of inflammatory bowel disease with an initial focus in Crohn's disease. A pivotal phase III programme of vercirnon was initiated in patients with moderate-to-severe Crohn's disease, however, the programme was suspended when the first pivotal trial failed to meet its primary endpoint. Phase II trials for ulcerative colitis and celiac disease were conducted, however investigations for ulcerative colitis were suspended while no further development has been reported for celiac disease.

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.

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.

Droloxifene, a derivative of the triphenylethylene drug tamoxifen, is a novel selective estrogen receptor modulator (SERM). Droloxifene also exhibits more rapid pharmacokinetics, reaching peak concentrations and being eliminated much more rapidly than tamoxifen. Its higher affinity to the estrogen receptor, higher anti-estrogenic to estrogenic ratio, more effective inhibition of cell growth and division in estrogen receptor-positive cell lines, and lower toxicity give it theoretical advantages over tamoxifen in the treatment of human breast cancer. Short-term toxicity was generally mild, and similar to that seen with other antiestrogens. Droloxifene appears active and tolerable. It may have a particular role in situations in which rapid pharmacokinetics, or an increased antiestrogenic to estrogenic ratio, are required. Droloxifene may also be a potentially useful agent for the treatment of postmenopausal osteoporosis because it can prevent estrogen deficiency-induced bone loss without causing uterine hypertrophy. Droloxifene may have an effect on bone and breast tissue because it induces apoptosis. Droloxifene has an anti-implantation effect in rats, and the effect appears to be not completely due to its anti-estrogenic activity.

Trefentanil is a short-acting synthetic opioid of the piperidine class. The drug caused potent analgesia with the peak effect occurring 3 min after injection. There was no significant difference in analgesic potency of trefentanil and alfentanil as measured by tolerance to tibial pressure at 3 min. Trefentanil had a pharmacokinetic and pharmacodynamic profile similar to alfentanil, with a small extent of tissue distribution and a rapid blood/brain equilibration. Trefentanil caused significant respiratory depression at doses of 32 ug/kg and 64 ug/kg. It is a mu-opioid receptor agonist. Trefentanil produced naloxone reversible anti-nociception equi-efficacious to that of fentanyl.

Metesind (AG-331) is a lipophilic thymidylate synthase inhibitor. It inhibits the cofactor binding site of the enzyme. It exerts cytotoxic properties. Metesind was being developed as an anticancer and antimetabolite agent.