Pictilisib is an oral potent inhibitor of class I PI3K with nanomolar activities against p110alpha, p110beta, p110delta, and p110gamma. The drug was developed for the treatment of solid tumors and reached phase II in patients with breast cancer and lung carcinoma, however its development was terminated.

APTO-253 is a novel small molecule that can induce expression of the genes that code for the Krüppel-like factor 4 (KLF4) master transcription factor and for the p21 cell cycle inhibitor protein, and can inhibit expression of the c-Myc oncogene, leading to cell cycle arrest and programmed cell death (apoptosis) in human-derived solid tumor and hematologic cancer cells. A Phase 1 study with APTO-253 was completed and demonstrated modest clinical activity in patients with colon cancer, acute leukemia, myelodysplastic syndrome, hematological malignancies and non-small cell lung cancers.

Buparlisib (NVP-BKM12), a dimorpholino pyrimidine derivative, is a selective pan class I phosphatidylinositol-3 kinase (PI3K) inhibitor for treating cancer. It penetrates the blood-brain barrier and has a potential as a glioma treatment. NVP-BKM120 inhibits PI3K activity by binding to the ATP binding cleft of this enzymes and was tested against class I PI3K and other kinases using an ATP depletion (Kinase-Glo) assay. The compound was shown to be active against P110 α, β, γ and δ. The inhibition of the PI3K signaling pathways leads to different forms of cell death on the basis of p53 statuses. Buparlisib demonstrated its activity in human glioblastoma (GBM) cells in vitro and in vivo and is in clinical trials for solid tumors including GBM.

Onalespib (AT13387; (2,4-dihydroxy-5-isopropyl-phenyl)-[5-(4-methyl-piperazin-1-ylmethyl)-1,3-dihydro-isoindol-2-yl] methanone, l-lactic acid salt), is wholly owned by Astex, a novel, high-affinity HSP90 inhibitor, which is currently being clinically tested, has shown activity against a wide array of tumor cell lines, including lung cancer cell lines. As a targeted inhibitor of Hsp90, onalespib has the potential to control the proliferation of multiple solid tumors and hematological malignancies where uncontrolled cell growth is dependent on the interaction between Hsp90 and its client proteins. Astex is pursuing an approach based on the observation that addition of onalespib to a molecularly targeted agent may delay the emergence of resistance to the agent, and hence prolong the window of therapeutic benefit. Onalespib is currently being evaluated via a CRADA with the National Cancer Institute (NCI) in various tumor types, and in a Phase 1/2 clinical study in combination with AT7519, Astex CDK inhibitor.

Tasisulam sodium, previously known as LY573636, were initially recognized by Eli Lilly for their significant antiproliferative activities in solid tumor cell lines, but their mechanism of action was unknown. Subsequent studies have revealed that LY573636 induces apoptosis via a mitochondrial-mediated mechanism that appears unique among other anti-cancer compounds. This drug was in the phase III clinical trial for the treatment of Metastatic Melanoma and in phase II for the treatment Non-Small-Cell Lung Cancer, breast cancer, ovarian cancer, but these studies were discontinued. In vivo pharmacokinetic studies in rats and dogs indicate that tasisulam is metabolized primarily by the liver, and has low total plasma clearance with a relatively long half-life. In addition, there was preclinical evidence of a correlation between the maximum plasma concentration (Cmax) of tasisulam and toxicity.

Dinaciclib (SCH 727965) is a small molecule inhibitor of cyclin-dependent kinases. Dinaciclib demostrates potent and selective inhibition of CDK2, CDK5, CDK1, and CDK9 activity. Dinaciclib inhibits cell cycle progression and proliferation in various tumor cell lines in vitro. Dinaciclib is a product of a drug discovery collaboration between Pharmacopeia (later Ligand Pharmaceuticals) and Schering-Plough (later Merck & Co.) that began in 1998. Dinaciclib showed promising effect in treating haematological malignancies and solid tumors.

Volasertib (BI 6727), a dihydropteridinone derivative, is a small-molecule cell cycle inhibitor of polo-like kinase-1 (PLK-1). Volasertib induces G2-M arrest and induction of apoptosis in cancer cells and potently inhibits tumor growth in xenograft models. Boehringer Ingelheim is developing intravenously administered volasertib for the treatment of acute myeloid leukaemia (AML), myelodysplastic syndromes (MDS), chronic myelomonocytic leukaemia (CMML), non-small cell lung cancer, urogenital cancer, ovarian cancer and solid tumours.

Dofequidar (MS-209), a quinolone-derived sphingomyelin synthase inhibitor that blocks P-glycoprotein and multidrug resistance-associated protein-1, is under development by Schering for the potential treatment of multidrug resistant tumors. MS-209 had been in phase III clinical trials for the treatment of breast cancer and non-small lung cancer. But this research was discontinued in 2004. Detected adverse events are: nausea, vomiting, leukopenia, neutropenia, anorexia, constipation.

Veliparib (ABT-888) is a potent inhibitor of PARP, has good oral bioavailability, can cross the blood-brain barrier, and potentiates temozolomide, platinums, cyclophosphamide, and radiation in syngeneic and xenograft tumor models. AbbVie is developing veliparib for the treatment of cancers. Clinical trials are underway worldwide, investigating veliparib primarily as part of a combination therapy in oncology indications such as brain, colorectal, melanoma, ovarian, prostate and pancreatic cancers.

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.