CG-200745 is a novel inhibitor of histone deacetylases (HDACs), initially developed by CrystalGenomics, Inc for treatment of various hematological and solid cancers. Combinations of CG-200745 with SN38 (the active form of irinotecan), or oxaliplatin were more effective than the agents alone when used to inhibit the growth of HCT116 cells. The protein expressions of acetyl-H3, p21, caspase-3, -8, and -9, PARP, and XIAP were affected in a time- and dose-dependent manner in HCT116 cells treated with the CG-200745 alone or combined CG-200745 and SN-38. In HCT116 xenografts, the HDACI CG-200745 in combination with irinotecan dramatically inhibited tumor growth without showing additive toxicity.

PTX-008 (OTX008) is a calixarene-based compound and galectin-1 (Gal-1) inhibitor with potential anti-angiogenic and antineoplastic activities. Upon subcutaneous administration, galectin-1 inhibitor OTX008 binds Gal-1 which leads to Gal-1 oxidation and proteosomal degradation through a not yet fully elucidated mechanism, and eventually downregulates Gal-1. This decreases tumor cell growth and inhibits angiogenesis. Gal-1, a multifunctional carbohydrate-binding protein, is often overexpressed on tumor cells and plays a key role in cancer cell proliferation, apoptosis, tumor angiogenesis and evasion of immune responses. PTX-008 had been in phase I clinical trials for the treatment of solid tumours. This compound was originally discovered by University of Minnesota and PepTx, then licensed to OncoEthix (acquired by Merck Sharp & Dohme in 2014). However, no recent developments has been reported.

DB09173 (Butyrfentanyl or butyrylfentanyl) is a potent, short-acting mu opioid receptor agonist, and an analog of fentanyl, differing by only one methyl group. It has no approved medical indications but is being used for recreational purposes, with cases of fatal overdoses reported in Europe and the United States. Pre-clinical studies of butyrfentanyl are scarce; however, the few available studies suggest that butyrfentanyl is about 30 times less potent than fentanyl itself, and has significant antinociceptive properties, as demonstrated by the acetic acid writhing test in rodents. DB09173 is being abused for its opioid effects. As with other mu-opioid agonists, it can induce respiratory depression which may lead to death and numerous deaths have been reported. No studies of butyrfentanyl dependence or cross-dependence conducted in humans could be identified.