Mitozolomide is an antineoplastic agent patented by May and Baker Ltd for cancer treatment. Development of mitozolomide was discontinued during Phase II clinical trials after it was found to cause severe and unpredictable bone marrow suppression.

Metamelfalan is an antineoplastic agent. Metamelfalan is the meta form of the levo isomer melphalan. Metamelfalan causes crosslinking of DNA, thereby preventing DNA replication and eventually cellular proliferation.

Ispinesib (SB-715992) is a potent, specific and reversible inhibitor of kinesin spindle protein (KSP). KSP, also known as HsEg5, is a kinesin that plays an essential role in the formation of a bipolar mitotic spindle and is required for cell cycle progression through mitosis. Ispinesib is the highly specific small-molecule inhibitor of KSP tested for the treatment of human disease. It causes mitotic arrest and growth inhibition in several human tumor cell lines and is currently being tested in multiple phase II clinical trials for treatment of the breast cancer and renal cell cancer.

Tafluposide (also known as F 11782) is an epipodophyllotoxin derivative patented by Pierre Fabre Medicament as an antitumor agent. Tafluposide acts as a catalytic inhibitor of topoisomerases I and II, that capable of completely inhibiting the DNA-binding activity of topoisomerase. In preclinical models single or multiple i.p. doses of Tafluposide proves highly active against the s.c. grafted B16 melanoma, significantly increasing survival and inhibiting tumor growth. Tafluposide inhibits the number of pulmonary metastatic foci of the melanoma by 99%. In human tumor xenograft studies, multiple i.p. doses of Tafluposide results in major inhibitory activity against breast) tumors, as well as causing definite tumor regression. Significant activity was also recorded Tafluposide against the refractory lung xenografts.

Nemorubicin, a doxorubicin derivative, is a DNA-intercalator, topoisomerase and RNA synthesis inhibitor that was undergoing development with Nerviano Medical Sciences (Nerviano MS; formerly Pharmacia Italia) for the treatment of solid tumours, specifically, the loco-regional treatment of primary liver tumours (hepatocellular carcinoma). The drug is active on tumors resistant to alkylating agents, topoisomerase II inhibitors and platinum derivatives. It works primarily through topoisomerase I inhibition. Of note, Nemorubicin is active in cells with upregulation of the nucleotide excision repair (NER) pathway, where current therapies fail. Nemorubicin is biotransformed in the liver into cytotoxic metabolites that may further contribute to render this drug highly active against primary liver tumors or liver metastases. Clinical trials were conducted in Europe, US and China with Nemorubicin given at different dose-schedules and by different routes of administration: as single agent by systemic IV route, oral route and by intra-hepatic artery (IHA) infusion alone or in combination with cisplatin.

Pazelliptine (previously known as BD 40 or SR 95225A) was developed as an antitumor drug that binds to the DNA sequence, preferable to G-C rich region and thus produces cellular DNA lesions. This drug was undergoing phase II trials in France for the treatment of cancer. However, this study was discontinued.

Salirasib or S-trans,trans-Farnesylthiosalicylic acid (FTS) is a salicylic acid derivative with potential antineoplastic activity. It acts as a potent competitive inhibitor of the enzyme prenylated protein methyltransferase (PPMTase), which methylates the carboxyl-terminal S-prenylcysteine in a large number of prenylated proteins including Ras. In such systems, Salirasib inhibits Ras methylation but not Ras farnesylation. Salirasib selectively disrupts the association of chronically active Ras proteins with the plasma membrane. Salirasib competes with Ras for binding to Ras-escort proteins, which possess putative farnesyl-binding domains and interact only with the activated form of Ras proteins, thereby promoting Ras nanoclusterization in the plasma membrane and robust signals. Salirasib was studied in the clinical trials in patients with solid tumors, however its development was discontinued.

Sagopilone (BAY86-5302; ZK 219477; ZK-EPO) is a synthetic epothilone, an analog of patupilone that was developed by Bayer HealthCare as an anticancer agent. Epothilones are 16-member ring macrolides have demonstrated potent antiproliferative activity in several different multidrug-resistant and paclitaxel-resistant tumor cell lines in vitro and in vivo. Sagopilone binds to tubulin and induces microtubule polymerization, which may result in the induction of G2/M arrest, and apoptosis. Sagopilone is not a substrate for the P-glycoprotein efflux pump and so may exhibit activity in multidrug-resistant tumors. This drug was studied in clinical trials phase II in patients with recurrent ovarian cancer, in metastatic melanoma patients, for the treatment of advanced stage breast cancer and in the treatment of Glioblastoma patients. However, the development of this drug was discontinued, because of its adverse effects, including peripheral neuropathy.

Alvespimycin (17-desmethoxy-17-N,N-dimethylaminoethylamino-geldanamycin) (17-DMAG; NSC 707545) is an inhibitor of the molecular chaperone heat shock protein HSP90. Alvespimycin is a derivative of antineoplastic benzoquinone antibiotic geldanamycin. Alvespimycin binds to HSP90, a chaperone protein that aids in the assembly, maturation and folding of proteins. Subsequently, the function of Hsp90 is inhibited, leading to the degradation and depletion of its client proteins such as kinases and transcription factors involved with cell cycle regulation and signal transduction. Alvespimycin was studied in clinical trials for the treatment of solid tumors and hematologic malignancies however its development was discontinued.