IRDABISANT is a histamine H3 receptor inverse agonist with potential therapeutic utility in cognition enhancement.

Talabostat is a prolineboronate ester derivative patented by Boehringer Ingelheim Pharmaceuticals, Inc. as an antineoplastic agent. Talabostat inhibits dipeptidyl peptidases, such as fibroblast activation protein (FAP), resulting in the stimulation of cytokine and chemokine production and specific T-cell immunity and T-cell dependent activity. Talabostat has been shown to cause caspase-1 activation and IL-1β induction in macrophages, which in turn causes upregulation of the cytokines and chemokines that characterize the responses to talabostat, both in vitro and in tumor-bearing mice. Talabostat may also stimulate the production of colony stimulating factors, such as granulocyte colony stimulating factor (G-CSF), resulting in the stimulation of hematopoiesis. In clinical trials, the combination of talabostat and cisplatin was well tolerated compared to historical data using cisplatin alone. The most frequent adverse events were nausea, vomiting, fatigue, anemia, edema, and constipation. Unfortunately was no evidence that Talabostat enhanced the clinical activity of other anticancer drugs and further development was discontinued.

Talisomycin (former trivial name: tallysomycin A), a third generation bleomycin analog that was studied as an antitumor antibiotic. The drug cleaved DNA preferentially at G-C and G-T sequences and produced specific cleavages at G-A sequences. Talisomycin participated in phase II clinical trial for the treatment of cancer; however, the further development of the drug was discontinued.

LY-2090314 is a GSK-3alpha and GSK-3beta inhibitor developed by Eli Lilly. Phase 2 clinical trials of LY-2090314 as a signle agenst against acute leukemia did not show clinical benefit. LY-2090314 was studied in combination pemetrexed and carboplatin against solid tumors, and in combination with FOLFOX, gemcitabine, and nab-paclitaxel against pancreatic cancer.

Entinostat (MS-275) is an orally active, highly selective, small-molecule histone deacetylase inhibitor (HDACi) derived from benzamide. Entinostat preferentially inhibited HDAC1 versus HDAC3 and had no inhibitory activity toward HDAC8. The time to maximum plasma concentration (tmax) of entinostat ranged from 0.5 to 60h (median of 2h). Elimination of the drug was bi-exponential, with a terminal half-life of 30-80h. Entinostat is a well-tolerated that demonstrates promising therapeutic potential in both solid and hematologic malignancies. Its efficacy does not appear directly dose-related, and as such, more relevant biomarkers are needed to adequately assess its activity.

OSI-7904L is a liposomal formulation of the highly specific, noncompetitive thymidylate synthase inhibitor OSI-7904 (also known as GW1843, BW1843U89, and GS7904). The liposome formulation was developed to enhance the therapeutic index and dose schedule convenience of this potent antifolate compound. This drug was studied in phase II clinical trial in patients to treat head and neck cancer, gastroesophageal adenocarcinoma and advanced biliary cancer, but these studies were discontinued. As an example in case of OSI-7904L, was revealed that its activity was below a level of clinical relevance in advanced biliary tract cancer, providing only a small degree of disease stabilization.

5-Fluoro-2-deoxycytidine is a fluorinated pyrimidine analog antimetabolite with potential antineoplastic activity. As a prodrug, 5-fluoro-2-deoxycytidine is converted by intracellular deaminases to the cytotoxic agent 5-fluorouracil (5-FU). 5-FU is subsequently metabolized to active metabolites including 5-fluoro-2-deoxyuridine monophosphate (FdUMP) and 5-fluorouridine triphosphate (FUTP). FdUMP binds to and inhibits thymidylate synthase, thereby reducing the production of thymidine monophosphate, which leads to depletion of thymidine triphosphate and the inhibition of DNA synthesis and cell division. FUTP competes with uridine triphosphate (UTP) for incorporation into the RNA strand, which results in the inhibition of RNA and protein synthesis and cell proliferation. 5-Fluoro-2-deoxycytidine undergoing trials to test its effectiveness in treating cancer that has not responded to standard therapies.

Sufugolix (TAK-013 or 5-(N-benzyl-N-methylaminomethyl)-1-(2,6-difluorobenzyl)-6-[4-(3-methoxyureido)phenyl]-3-phenylthieno[2,3-d]pyrimidine-2,4(1H,3H)-dione) is a highly potent and orally active non-peptide antagonist of luteinizing hormone-releasing hormone (LHRH) receptor. Sufugolix by oral administration suppresses a pituitary-ovarian axis continuously and reversibly in cynomolgus monkeys. Takeda studied Sufugolix in the trials for the treatment of endometriosis and uterine leiomyoma however development was discontinued.

Resiquimod is an imidazoquinolinamine and Toll-like receptor (TLR) agonist with potential immune response modifying activity. Resiquimod exerts its effect through the TLR signaling pathway by binding to and activating TLR7 and 8 mainly on dendritic cells, macrophages, and B-lymphocytes. This induces the nuclear translocation of the transcription activator NF-kB as well as activation of other transcription factors. This may lead to an increase in mRNA levels and subsequent production of cytokines, especially interferon-alpha (INF-a) and other cytokines, thereby enhancing T-helper 1 (Th1) immune responses. In addition, topical application of resiquimod appears to activate Langerhans' cells, leading to an enhanced activation of T-lymphocytes. Resiquimod is used as a topical gel[1] in the treatment of skin lesions[2] such as those caused by the herpes simplex virus[3][4] and cutaneous T cell lymphoma. Due to its immunostimulatory activity, this agent may potentially be used as a vaccine adjuvant.

Losigamone possesses an unique anticonvulsant activity profile and has an excellent tolerability. Losigamone causes dose-dependent inhibition of the tonic hind leg extension produced by electric shock, pentylenetetrazole, bicuculline, nicotine and 4-aminopyridine. Losigamone also inhibits clonic seizures induced by pentylenetetrazole, bicuculline and picrotoxin, whereas it has no effect on the hind leg extension caused by strychnine and picrotoxin or the clonic seizures induced by NMDA. Losigamone had been in phase III clinical trial for the treatment of partial epilepsies. However, this development was discontinued.