Sudexanox is a xanthone derivative patented by French pharmaceutical company Roussel-UCLAF for the treatment of allergy, allergic asthma, and asthmatic bronchitis. In preclinical studies, Sudexanox possesses potent activity in the IgE-induced rat passive cutaneous anaphylaxis model.

CKD-516 is a prodrug of the tubulin binding agent S516, with potential tubulin-inhibiting, vascular-disrupting, and antineoplastic activity. Upon administration, tubulin polymerization inhibitor CKD-516 is converted into its active metabolite S-516, which binds to tubulin and prevents its polymerization in tumor blood vessel endothelial cells and tumor cells. This blocks the formation of the mitotic spindle and leads to cell cycle arrest at the G2/M phase. As a result, this agent disrupts the tumor vasculature and tumor blood flow, deprives tumor cells of nutrients and induces tumor cell apoptosis. In addition, this agent has a direct cytotoxic effect on tumor cells by inhibiting tubulin polymerization. CKD-516 is developed by a Korean company Chong Kun Dang Pharmaceutical Corp. and is investigated in a phase 1/2a clinical trial for the treatment of colorectal cancer in combination with Irinotecan.

Pobilukast is the Leukotriene D4 receptor antagonist. Pobilukast significantly attenuated the Salmonella enteritidis endotoxin-induced thrombocytopenia but had no effect on either the endotoxin-induced early leukopenia or late leukocytosis. Additionally, Pobilukast significantly reduced the endotoxin-induced hemoconcentration and improved survival to 30% at 48 hr. Pobilukast dose-dependently inhibited the immediate hemodynamic changes after leukotriene D4 (LTD4) injections. Pobilukast also attenuated the increase in vascular permeability and the prolonged decrease in CO, suggesting that the observed cardiac and vascular effects of LTs were mediated by stimulation of LT receptors. A shift toward the right of the dose-response curves to histamine with pobilukast compared to that with placebo in three subjects was demonstrated, whereas the active compound did not exhibit any protective effect against histamine in the remaining nine subjects. It was concluded that there is a leukotriene component to the bronchial responses to histamine in some, but not all, subjects. Pobilukast had been in phase II clinical trial for the treatment of asthma. However, this development was discontinued.

Lurtotecan is a semisynthetic analog of camptothecin with antineoplastic activity. It is an inhibitor of DNA topoisomerase I. Liposomal formulation of lurtotecan was being studied in the treatment of cancer. Lurtotecan development has been discontinued.

Nepicastat (SYN-117) is a potent and selective inhibitor of dopamine-β-hydroxylase. This compound in Phase 2 of clinical trial for the treatment cocaine addiction and posttraumatic stress disorder.

BI-2536, an inhibitor of Polo-like kinase 1 (Plk-1) was being investigated by Boehringer Ingelheim as a possible treatment for cancer. BI-2536 inhibits Plk1 enzyme activity at low nanomolar concentrations. The compound potently causes a mitotic arrest and induces apoptosis in human cancer cell lines of diverse tissue origin and oncogenome signature. BI-2536 inhibits growth of human tumor xenografts in nude mice and induces regression of large tumors with well-tolerated intravenous dose regimens. In treated tumors, cells arrest in prometaphase, accumulate phosphohistone H3, and contain aberrant mitotic spindles. This mitotic arrest is followed by a surge in apoptosis, detectable by immunohistochemistry and noninvasive optical and magnetic resonance imaging. For addressing the therapeutic potential of Plk1 inhibition, BI-2536 has progressed into clinical studies in patients with locally advanced or metastatic cancers. It underwent phase II clinical studies for the treatment of breast cancer; non-small cell lung cancer; pancreatic cancer; prostate cancer; small cell lung cancer, but these studies were discontinued later.

Tazadolene was developed as a novel non-opioid analgesic with antidepressant properties. Experiments on rodents have revealed that unique analgesia properties of tazadolene was due to the ability of this compound to activate both serotonergic and alpha 2 adrenergic antinociceptive systems. Information about the current use of this drug is not available.