Imazodan, a phosphodiesterase III inhibitor was developed by Parke-Davis to treat heart failure and ischemic heart disorders. However, the study of this drug was discontinued.

Terestigmine (also known as CHF-2060), a cholinesterase inhibitor, was developed for the treatment of cognition disorders in Italy. However, this study was discontinued.

Enazadrem (CP-70490-09) is an antipsoriatic agent inhibiting arachidonate 5-lipoxygenase.

Amuvatinib (formerly known as MP470) is an oral multi-targeted tyrosine kinase inhibitor, which play critical roles in transducing growth signals to cancer cells. It suppresses c-MET, c-RET and the mutant forms of cKIT, PDGFR and FLT3. It also disrupts DNA repair likely through suppression of homologous recombination protein Rad51, an important survival pathway in many human cancers. In vitro and in vivo data have demonstrated amuvatinib synergy with DNA damaging agents including etoposide and doxorubicin. Overall, in the amuvatinib clinical development program, over 200 subjects were exposed to at least one dose of amuvatinib. In the Phase 1b clinical study in combination with carboplatin and etoposide, responses in small cell lung cancer (SCLC), neuroendocrine as well as other tumor types were observed. Human pharmacokinetic data suggest that co-administration of amuvatinib did not alter exposures of standard of care agents including carboplatin, etoposide, doxorubicin, paclitaxel, topotecan or erlotinib as measured by overall exposure. In the first-in-human study, durable clinical benefit was observed in the gastrointestinal stromal tumors (GIST) with modulation of Rad51 observed in skin punch biopsies. In clinical trials, amuvatinib has demonstrated a wide therapeutic window and shows minimal toxicity in the expected therapeutic dose range, despite suppressing several signaling pathways within cells. However, in spite of this, this drug was discontinued, because it was not pre-specified primary endpoints in the clinical proof of concept (cPOC) stage. But the combination of MP470 and Erlotinib, which target the HER family/PI3K/Akt pathway may represent a novel therapeutic strategy for prostate cancer.

Lufironil (HOE 077) is an inhibitor of prolyl 4-hydroxylase. In preclinical studies, it prevented liver fibrosis by inhibiting not only the hydroxylation of proline but also the activation of Ito cells, which are considered the main collagen-producing cells, resulting in reduced expression of procollagen mRNA. Lufironil was being developed for the treatment of chronic liver diseases including alcoholic hepatitis and liver cirrhosis.

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.

Bemoradan (RWJ-22867), a potent positive inotropic agent, inhibits cardiac phosphodiesterase fraction III. This compound was developed for the management of congestive heart failure. However, the information about the nowadays study of bemoradan is not available.

Triapine (3-aminopyridine-2-carboxaldehyde thiosemcirbazone, (3-AP; NTO-1151; OCX-0191) is a novel small molecule ribonucleotide reductase inhibitor that acts on the M2 (R2) subunit. Ribonucleotide reductase is an enzyme involved in the de novo synthesis of deoxyribonucleotides, which are critical for DNA replication and DNA repair. Triapine has been used in trials phase II studying the treatment of Lung Cancer, Kidney Cancer, Prostate Cancer Pancreatic Cancer, among others. Recently was published the article describing, that the triple combination triapine-cisplatin-paclitaxel was safe and provided a rational basis for a follow-up phase II trial to evaluate the efficacy and progression-free survival in women with metastatic or recurrent uterine cervix cancer.