XK-469 (2-[4-(7-chloro-2-quinoxalinyloxy)phenoxy]-propionic acid) is a novel synthetic quinoxaline phenoxypropionic acid derivative. The R-isomer of XK-469 was approximately twice as effective as the S-isomer of XK-469R. R( )-isomers induce reversible protein DNA crosslinks in mammalian cells. It acts as a selective topoisomerase IIβ inhibitor. A phase I study was performed to determine the safety and pharmacokinetics of XK-469, (R)- in patients with various neoplasms.

Sodium taurodeoxycholate is a bile salt-related, anionic detergent used for isolation of membrane proteins including inner mitochondrial membrane proteins. It is formed by the conjugation of ursodeoxycholic acid (UDCA) with taurine. Sodium taurodeoxycholate and ursodeoxycholic acid are major constituents of black bear bile, which has been used in traditional Chinese medicine for thousands of years. Bear bile was historically employed to treat a number of diseases including jaundice, summer diarrhea, abdominal pain due to hepatobiliary diseases and gastric malfunction, biliary ascariasis, infectious skin diseases, the common cold, intestinal worms, and inflammation of the throat. Sodium taurodeoxycholate has been shown to inhibit apoptosis by modulating mitochondrial membrane perturbation and pore formation, B cell lymphoma 2 (Bcl-2)-associated protein X (BAX) translocation, cytochrome c release, and caspase activation. Sodium taurodeoxycholate inhibits amyloid beta (Ab)-induced apoptosis and attenuates the endoplasmic reticulum (ER) stress, which are thought to be key components of the pathological process in certain diseases. In clinical studies, Sodium taurodeoxycholate is shown to be very safe with oral administration of 1500 mg/day for up to 6 months. In a more recent clinical study, a dose of 1750 mg/day for up to 4 weeks was well tolerated in healthy obese persons. One of the major adverse effects of Sodium taurodeoxycholate is diarrhea. Based on the related information from ursodeoxycholic acid, other gastrointestinal side effects are possible including abdominal pain, flatulence, nausea, dyspepsia, and anorexia.

Evofosfamide, also formerly known as TH-302, is an investigational hypoxia-activated prodrug and is used to target cancerous cells under hypoxic conditions, which is a feature possessed by multiple solid tumors including glioblastoma and pancreatic cancer. Within regions of tumor hypoxia, evofosfamide releases bromo isophosphoramide mustard (Br-IPM), a potent DNA alkylating agent that kills tumor cells by forming DNA crosslinks. Once activated in hypoxic tissues, Br-IPM can also diffuse into surrounding oxygenated regions of the tumor and kill cells there via a “bystander effect”. Because of its preferential activation in the targeted hypoxic regions of solid tumors, evofosfamide may be less likely to produce broad systemic toxicity seen with untargeted cytotoxic chemotherapies.