1-(2-DEOXY-2-FLUORO-β-D-ARABINOFURANOSYL)URACIL (FAU) is a thymidine analog. In several cancer cell lines, FAU was phosphorylated intracellularly to its monophosphate, 1-(2-deoxy-2-fluoro--Darabinofuranosyl) uracil monophosphate (FAUMP), by thymidine kinase and methylated in the 5-position by thymidylate synthase to form the product, 1-(2-deoxy-2-fluoro- -D-arabinofuranosyl) 5-methyluracil monophosphate (FMAUMP). FAU strongly inhibits the growth of tumor cells with high thymidylate synthase activity. FAU had been in phase I clinical trial for the treatment of advanced solid tumors.

Iodide I-131 (as Sodium iodide I-131) is a radioisotopic drug used for the treatment and palliation of thyroid malignancy. Iodine-131 is notable for causing mutation and death in cells that it penetrates, which is due to its mode of beta decay. Iodide I-131 can be detected by gamma cameras for diagnostic imaging, however, it is rarely administered for diagnostic purposes only, imaging will normally be done following a therapeutic dose. Major uses of 131I include the treatment of thyrotoxicosis (hyperthyroidism) due to Graves' disease, and sometimes hyperactive thyroid nodules (abnormally active thyroid tissue that is not malignant). Iodine-131, in higher doses than for thyrotoxicosis, is used for ablation of remnant thyroid tissue following a complete thyroidectomy to treat thyroid cancer. The 131I isotope is also used as a radioactive label for certain radiopharmaceuticals that can be used for therapy, e.g. 131I-metaiodobenzylguanidine for imaging and treating pheochromocytoma and neuroblastoma. Because of the carcinogenicity of its beta radiation in the thyroid in small doses, I-131 is rarely used primarily or solely for diagnosis. Instead, the more purely gamma-emitting radioiodine iodine-123 is used in diagnostic testing. The longer half-lived iodine-125 is also occasionally used when a longer half-life radioiodine is needed for diagnosis, and in brachytherapy treatment, where the low-energy gamma radiation without a beta component makes iodine-125 useful.

Adarotene (ST1926) is a new pro-apoptotic and cytodifferentiating antitumour drug, belongs to the so-called class of atypical retinoids. Adarotene is active on its own or in combination with other chemotherapeutics for the treatment of a vast number of experimental tumors. It was found in preclinical investigations the potential therapeutic use it in chronic myeloid leukemia (CML), against Rhabdomyosarcoma and for treatment of Adult T-cell leukemia/lymphoma (ATL). ST1926 induced an early DNA damage response, which led to increase in apoptosis, in addition to S-phase cell cycle arrest and a reduction in protein levels of the cell cycle kinase CDK1. The presence of the phenolic hydroxyl group on adarotene structure allows a rapid O-glucuronidation as a major mechanism of elimination of the drug, favoring a fast excretion of its glucuronide metabolite in the urines.

British Biotech was developing solimastat [BB 3644], an inhibitor of tumour necrosis factor and matrix metalloproteinase, as a potential treatment for colorectal cancer, inflammatory bowel diseases and rheumatoid arthritis. BB-3644 is an oral, broad-spectrum matrix metalloproteinase inhibitor (MMPI) structurally related to marimastat and BB-94. It is also >10-fold more active than marimastat in inhibiting the processing of cell-bound TNF-alpha. Solimastat development has been discontinued due to significant musculoskeletal toxicity.

Farmitalia-Carlo Erba developed minamestane (code name FCE-24928) as a steroidal aromatase inhibitor for the treatment of cancer. This drug was in phase I clinical trial in Italy, but development was discontinued.

JNJ-26854165 (Serdemetan), a novel tryptamine derivative, was developed as an activator of p53, and its initially proposed mechanism of action involved preventing the association of HDM2 with the proteasome and thereby stabilizing HDM2 substrates such as p53. Consistent with this proposed mechanism, Serdemetan induced apoptosis in acute myeloid and lymphoid leukemia cell lines and in primary acute leukemia isolates. Serdemetan is currently being evaluated in Phase I clinical trials in patients with non-small cell lung cancer; prostate cancer; solid tumours.

Bafetinib (NS-187, INNO-406) is a second-generation tyrosine kinase inhibitor in development by CytRx under license from Nippon Shinyaku for treating Bcr-Abl+ leukemia's, including chronic myelogenous leukemia (CML) and Philadelphia+ acute lymphoblastic leukemia. It is a rationally developed tyrosine kinase inhibitor based on the chemical structure of imatinib, with modifications added to improve binding and potency against Bcr-Abl kinase. Besides Abl, bafetinib targets the Src family kinase Lyn, which has been associated with resistance to imatinib in CML. In preclinical studies, bafetinib was 25- to 55-fold more potent than imatinib in vitro and ≥ 10-fold more potent in vivo. Bafetinibinhibits 12 of the 13 most frequent imatinib-resistant Bcr-Abl point mutations, but not a Thr315Ile mutation. A small fraction of bafetinib crosses the blood-brain barrier, reaching brain concentrations adequate for suppression of Bcr-Abl+ cells. Data from a phase I clinical trial conducted in patients with imatinib-resistant or -intolerant CML have confirmed that bafetinib has clinical activity in this setting, inducing a major cytogenetic response in 19% of those patients in chronic phase. Currently, bafetinib is being developed in two phase II clinical trials for patients with B-cell chronic lymphocytic leukemia and prostate cancer, and a trial is in progress for patients with brain tumors. In 2005, the compound was licensed to Innovive Pharmaceuticals (acquired by CytRx Oncology in 2008) by Nippon Shinyaku on a worldwide basis, with the exception of Japan, for the treatment of CML. Orphan drug designation was assigned to the compound for the treatment of CML in the U.S in 2007 and in the E.U. in 2010. Bafetinib is in phase II for the treatment of hormone-refractory prostate cancer and chronic lymphocytic leukemia.

Ombrabulin is an experimental drug candidate discovered by Ajinomoto and further developed by Sanofi-Aventis for cancer treatment. Ombrabulin is a synthetic water-soluble analog of combretastatin A4, derived from the South African willow bush (Combretum caffrum), with potential vascular-disrupting and antineoplastic activities. Ombrabulin binds to the colchicine binding site of endothelial cell tubulin, inhibiting tubulin polymerization and inducing mitotic arrest and apoptosis in endothelial cells. As apoptotic endothelial cells detach from their substrate, tumor blood vessels collapse; the acute disruption of tumor blood flow may result in tumor necrosis. Ombrabulin has been used in trials studying the treatment of Sarcoma, Neoplasms, Solid Tumor, Neoplasms, Malignant, and Advanced Solid Tumors, among others. In January 2013, Sanofi said it discontinued development of Ombrabulin after disappointing results from phase III clinical trials.

Talarozole (formerly R115866) is a new highly potent and selective azole derivative, which inhibits cytochrome-P450-dependent all-trans-retinoic acid catabolism by blocking the cytochrome P450 enzyme isoform CYP26, a retinoic acid hydroxylase. It is in clinical development for the treatment of psoriasis and acne. However, no local pharmacokinetic data on the diffusion behaviour of talarozole in the skin itself are available. As topical application might be an interesting alternative to oral therapy because of the reduced systemic side effects. The distribution of talarozole within the skin was investigated: 80% was located in the epidermis, while the remaining 20% was found in the dermis. The epidermal concentration of talarozole achieved after a single topical application was sufficiently high to enable the potential induction of local retinoid-like effects.

Misonidazole is a nitroimidazole with radiosensitizing and antineoplastic properties. Exhibiting high electron affinity, misonidazole induces the formation of free radicals and depletes radioprotective thiols, thereby sensitizing hypoxic cells to the cytotoxic effects of ionizing radiation. This single-strand breaks in DNA induced by this agent result in the inhibition of DNA synthesis. The drug also possesses a substantial cytotoxic effect, independent of radiation, which is selectively expressed in hypoxic cells. Misonidazole may be cytotoxic to the normal hypoxic tissues in the human body, making this became a major concern in the clinical application of the drug. Misonidazole leads to strand breaks in cellular DNA and those cells which fail to survive also fail to repair these strand breaks. Misonidazole depletes intracellular glutathione and is more toxic in glutathione depleted cells.