Patupilone is a compound isolated from the myxobacterium Sorangium cellulosum. Similar to paclitaxel, Patupilone induces microtubule polymerization and stabilizes microtubules against depolymerization conditions. In addition to promoting tubulin polymerization and stabilization of microtubules, this agent is cytotoxic for cells overexpressing P-glycoprotein, a characteristic that distinguishes it from the taxanes. Epothilone B may cause complete cell-cycle arrest. Patupilone failed a phase III trial for ovarian cancer in 2010.

Fluperlapine is dibenzazepine chemically and pharmacologically similar to clozapine. Fluperlapine had no cataleptogenic effect and did not inhibit the apomorphine- and d-amphetamine-induced stereotypes. Fluperlapine is fairly effective neuroleptic drug with a fast-acting antipsychotic affect. The effects in movement disorders imply that fluperlapine is less liable than traditional neuroleptics to induce acute extrapyramidal side effects and tardive dyskinesia and is particularly beneficial in the treatment of patients vulnerable to neurological side-effects. It was demonstrated efficacy in the treatment of a variety of medical conditions including schizophrenia, psychosis associated with Parkinson's disease and dystonia. It has the capacity for producing life-threatening agranulocytosis.

Apricitabine (ATC) is an investigational drug that was being studied for the treatment of HIV infection. Apricitabine belongs to a class (group) of HIV drugs called nucleoside reverse transcriptase inhibitors (NRTIs). NRTIs block an HIV reverse transcriptase. By blocking reverse transcriptase, NRTIs prevent HIV from multiplying and can reduce the amount of HIV in the body. In vitro studies have shown that apricitabine appears to work on certain HIV strains against which other FDA-approved NRTIs, such as lamivudine (brand name: Epivir), may no longer work. Apricitabine shows antiviral activity in vitro against HIV-1 strains and clinical isolates with mutations in the reverse transcriptase that confer resistance to other NRTIs, including M184V, thymidine analogue mutations (TAMs), nucleoside-associated mutations such as L74V and certain mutations at codon 69. Apricitabine has shown activity in treatment-experienced HIV-1-infected patients with NRTI resistance (with M184V and up to five TAMs) as well as in treatment-naive patients. The study of apricitabine as an HIV medicine was discontinued in 2016. The company developing the drug decided to stop their clinical trials due to a lack of funding and a lack of interest in apricitabine’s early access program.

Tanaproget (WAY-166989) is a nonsteroidal progesterone receptor agonist. It has been in Phase-II clinical trials as an oral contraceptive. The compound demonstrated a positive preclinical pharmacological profile in the treatment of endometriosis. The level of progesterone receptors in breast tumours can be used to guide the selection of endocrine therapies for breast cancer patients. Radiolabeled analogues of tanaproget have diagnostic potential as PET imaging agents for breast cancer.

Hydroxytamoxifen (Afimoxifene) is an active metabolite of tamoxifen exerting estrogen receptor modulatory function. In addition, hydroxytamoxifen binds to regulates transcriptional activity of the estrogen-related receptor gamma. ASCEND Therapeutics, Inc. was developing TamoGel (4-hydroxytamoxifen gel) for a variety of estrogen-dependent conditions, including breast cancer, cyclic breast pain and gynecomastia.

Brivanib is a pyrrolotriazine-based compound and an inhibitor of vascular endothelial growth factor receptor-2 (VEGFR-2) with potential antineoplastic activity. It specifically targets and strongly binds to human VEGFR-2, a tyrosine kinase receptor and pro-angiogenic growth factor expressed almost exclusively on vascular endothelial cells. Blockade of VEGFR-2 by this agent may lead to an inhibition of VEGF-stimulated endothelial cell migration and proliferation, thereby inhibiting tumor angiogenesis. Brivanib has a moderate potency compared to VEGFR-2 against VEGFR-1 and FGFR-1 as well. Brivanib is suggested to be efficient in treatment of hepatocellular carcinoma (HCC). As first-line and as second-line therapy brivanib demonstrated promising antitumor activity and a manageable safety profile in patients with advanced, unresectable HCC in phase II clinical trials. On 3 march 2011, orphan designation was granted by the European Commission to Bristol-Myers Squibb for brivanib alaninate for the treatment of hepatocellular carcinoma.[

Eprodisate (1,3-propanedisulfonate) is a negatively charged, sulfonated molecule of low molecular weight that has structural similarities to heparin sulfate; it is a glycosaminoglycan mimetic that binds to the glycosaminoglycan (GAG) binding site on serum A amyloid (AA) to prevent its interaction with glycosaminoglycan and arrest amyloidosis, or inhibit amyloid deposition. In nonclinical toxicity studies in two animal species (i.e., rat and dog), eprodisate was administered orally at doses of up to 2000 mg/kg/day for 39 weeks: eprodisate showed low toxicity potential at doses several fold higher than the anticipated clinical dose, was well tolerated upon chronic exposure and was found to be nonmutagenic and nonclastogenic. Furthermore, a series of safety pharmacology studies showed that eprodisate does not have any clinically significant effect on major organ function.

Edaglitazone have a clear PPAR-gamma agonist profile, with predominant PPAR-gamma activity and little PPAR-alpha activity. Edaglitazone was reported to significantly improve insulin sensitivity and enhance the rate of glucose oxidation in both the presence and absence of insulin. Additional studies have shown that edaglitazone affects muscle glucose metabolism by additional mechanisms other than PPAR-gamma activation. Phase I clinical studies have revealed that edaglitazone is well-tolerated and capable of significantly improving glucose homeostasis. Edaglitazone had been in phase II clinical trials for the treatment if type 2 diabetes. However, this research has been discontinued.

Marimastat is a broad spectrum matrix metalloprotease (MMP) inhibitor. It is an angiogenesis and metastasis inhibitor. It mimics the peptide structure of natural MMP substrates and binds to matrix metalloproteases, thereby preventing the degradation of the basement membrane by these proteases. This antiprotease action prevents the migration of endothelial cells needed to form new blood vessels. Inhibition of MMPs also prevents the entry and exit of tumor cells into existing blood cells, thereby preventing metastasis. Marimastat has been in pivotal phase III trials in glioblastoma, breast, ovarian and small and non-small cell lung cancer, but these trials have all been discontinued because marimastat failed to show superior efficacy over either standard chemotherapy or placebo.

CI 1040 is an inhibitor of the mitogen-activated protein (MAP) kinase signal transduction pathway and has been shown to specifically inhibit MAP kinase kinase (MEK). CI 1040 was being developed by Parke-Davis (formerly a division of WarnerLambert, Now Pfizer) as an anticancer agent. It was the initial MEK inhibitor to undergo clinical evaluation based on promising preclinical activity. However, its development has been discontinued.