Enloplatin (CL 287110) is a platinum complex with antineoplastic properties. It is more water soluble than cisplatin. Enloplatin was developing by Wyeth-Lederle for the treatment of patients with ovarian cancer and leukemia.

Refametinib (RDEA-119, BAY- 869766) is a highly potent and selective inhibitor of mitogen-activated ERK kinase (MEK1/2) activity, Refametinib binds to an allosteric pocket adjacent to the ATP binding site, locking the enzyme in a catalytically inactive conformation. This compound is highly efficacious at inhibiting cell proliferation in several tumor cell lines in vitro. In vivo, Refametinib exhibits potent activity in xenograft models of cancers. Ardea Biosciences (a subsidiary of AstraZeneca) and Bayer HealthCare are developing refametinib for the treatment of cancer. The sulfonamide agent was originally developed by Valeant Pharmaceuticals International. Refametinib is in phase II development for hepatocellular carcinoma, and phase I/II development for pancreatic cancer and other solid tumours.

Ritrosulfan (also known as R-74 and Lycurim) is a sulfonate-based alkylation agent that might exert antineoplastic activity, acting to stop the development of a tumor. By alkylating DNA and producing crosslinks, ritrosulfan is thought to cause tumor cell cycle arrest. However, no alkylating activity could be demonstrated in the plasma of cancer patients, using intracavitary application of ritrosulfan. Other studies in the 1980’s have confirmed some immunodepressive properties of ritrosulfan in cancer patients, but no information is available on current development of ritrosulfan.

Pibrozelesin (KW-2189) is a semisynthetic water-soluble derivative of the antineoplastic antibiotic duocarmycin B2. Activated by carboxyl esterase, pibrozelesin alkylates DNA by binding to adenine-thymine (A-T)-rich sequences in the minor groove of DNA, thereby inhibiting DNA replication and inducing apoptosis. KW-2189 induced DNA strand breaks in H69 cells in a concentration-dependent manner. DNA cleavage is one of the major mechanisms of KW-2189-mediated cytotoxicity. KW-2189 showed evidence of anti-tumor activity in hepatocellular carcinoma (HCC). However, because of significant and prolonged hematologic toxicity, when given as a single dose every 6 weeks, further development of this drug in HCC is not possible. Pibrozelesin had been in phase II clinical trial for the treatment of advanced malignant melanoma and advanced renal cell carcinoma. No activity in metastatic renal cell carcinoma was demonstrated and the lack of significant antitumor activity in advanced malignant melanoma treatment was shown.

Plinabulin (formerly known as NPI-2358) is a potent microtubule-destabilizing agent that exerts its effect by binding to the colchicine-binding site of tubulin. Plinabulin projects its potent antitumor activity against a broad spectrum of tumor cell lines. This drug in combination with docetaxel is under development by BeyondSpring Pharmaceuticals in a worldwide Phase 3 clinical trial for non-small cell lung cancer. Pegfilgrastim is also in phase II clinical trial for the prevention of chemotherapy-induced neutropenia, where docetaxel, doxorubicin, and cyclophosphamide (TAC) were used as the chemotherapy. Plinabulin also possessed antitumor activity in animal models with multiple myeloma cancer cells, where the JNK protein appeared to be a primary target of plinabulin.

Flurocitabine is an anti-metabolite that was developed by Hoffmann-La Roche for the treatment of cancer. The drug is metabolized to 2 biologically active substances, AFC (1-beta-D-arabinofuranosyl-5-fluorocytosine) and AFU (arabinofuranosyl-5-fluorouracil). Flurocitabine was tested against stomach cancer, pancreatic cancer, small cell lung cancer and AML, however, the development was terminated in the early phases.

Temarotene (also known as Ro 15-0778), the arotinoid with immunosuppressive and immunostimulatory activities. Temarotene was also studied as a chemopreventive agent. Information about the current development of this compound is not available.

Sonolisib (PX-866) is a small-molecule inhibitor of the alpha, gamma, and delta isoforms of phosphoinositide 3-kinase (PI3K) with potential antineoplastic activity. Sonolisib inhibits the production of the secondary messenger phosphatidylinositol-3,4,5-trisphosphate (PIP3) and activation of the PI3K/Akt signaling pathway, which may result in inhibition of tumor cell growth and survival in susceptible tumor cell populations. Inhibition of the PI3K pathway with Sonolisib leads to inhibition of cell growth and decreased activation of downstream targets in GBM, both in vitro and in vivo, using U87–tumor-bearing mice, including Akt, S6, and mTOR. Sonolisib was in phase II clinical trials by Oncothyreon for the treatment of glioblastoma multiforme and castration-resistant prostate cancer (CRPC). It was in phase I/II clinical trials for the treatment of malignant melanoma, non-small cell lung cancer and Head and neck cancer. In clinical trials, Sonolisib was well tolerated, with common side effects being diarrhea, nausea, vomiting, and elevated liver enzymes. However, no recent development has been reported.

Tesmilifene is a small-molecule antineoplastic drug and chemopotentiator that was under development by YM BioSciences for the treatment of breast cancer. Tesmilifene was developed as a selective ligand of the antiestrogen binding sites without estrogen receptor affinity. Tesmilifene potentiates the cytotoxicity of a variety of chemotherapy drugs in vitro and in vivo. Tesmilifene in combination with doxorubicin provides an unexpected and very large survival advantage over doxorubicin alone in a randomized trial in phase III clinical trial in advanced breast cancer. Unfortunately, Tesmilifene application associated with high rate disease and treatment-related adverse events and poor quality of life. Based on these results further development of Tesmilifene was discontinued

Mitonafide is a nitro-containing antitumor drug. Mitonafide participated in clinical trials phase II in colorectal cancer patients, however, the results have shown that the drug was not active and induced severe myelotoxicity. Besides, the drug was involved in phase II for the patients with non-small cell lung cancer (NSCLC), where it was not active in spite of the safe administration. Information about the current development of this drug is not available.