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.

Piquindone is an antipsychotic pyrroloisoquinoline derivative that binds to dopamine D2 receptors. It is a potent D-2 antagonist. It has a low potential for extrapyramidal effects and tardive dyskinesia. Piquindone exhibited relatively weaker cataleptogenic and antistereotypic activity than haloperidol, and had minimal activity in a rat chronic stereotypy model of receptor supersensitivity. Piquindone almost as potent as haloperidol, with fewer or less intense extrapyramidal effects and low potential for tardive dyskinesia. Piquindone led to moderate but significant improvements in the positive symptoms of schizophrenia and to improvements in negative symptoms just below the level of statistical significance. Therapeutic efficacy of a piquindone antagonist in Tourette Syndrome can be achieved without production of disabling extrapyramidal-side effects.

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.

Altanserin is a potent and selective 5-HT2A receptor antagonist. Serotonin (5-HT) system functioning have been proposed for a variety of psychiatric disorders, but a direct method quantitatively assessing 5-HT release capacity in the living human brain is still lacking. It was suggested that the combination of a dexfenfluramine-induced 5-HT release and subsequent assessment of 5-HT(2A) receptor availability with [(18)F]altanserin by positron emission tomography (PET) was suitable to measure cortical 5-HT release capacity in the human brain. Besides human neuroimaging studies altanserin has also been used in the study of rats.

LEDOXANTRONE, a benzothiopyranoindazole, is an intercalating agent. Its mechanism of action is probably due to DNA helicase blockade. It was under development for the treatment of prostate and ovarian cancers.

Beperidium (also known as SX-810 ) is a competitive antagonist against acetylcholine. Experiments on animal have shown that this compound exhibited spasmolytic and antiulcerative activities without exerting systemic antimuscarinic side effects.

Fedotozine [(1R)-1-phenyl-1-[(3,4,5-trimethoxy) benzyloxymethyl]-N,N- dimethyl-n-propylamine, (2S,3S-tartrate], derived from the arylacetamide series, is an opioid drug which acts as a selective agonist for kappa(1a)-opioid receptor. Pharmacological studies have shown that fedotozine exerts a peripheral antinociceptive action, comparable with that of other kappa-agonists. Results of Phase III trials of fedotozine against irritable bowel syndrome and dyspepsia have ultimately been disappointing and was lack of efficacy in subsequent studies.