Resiniferatoxin (RTX or RTX-107) is a vanilloid derived from a cactus-like plant (Euphoria resiniferous) and has anti-inflammatory activity. This compound is an agonist of the transient receptor potential vanilloid 1 (TRPV1). Resiniferatoxin produces analgesia by desensitizing the TRPV1 receptor. Findings of several studies have suggested a potential therapeutic use of the anti-inflammatory effect of resiniferatoxin. Phase I and II clinical trials have been completed or are underway, evaluating the safety and efficacy of resiniferatoxin in pain-related disorders such as osteoarthritis and cancers.

Nerofe, the flagship compound of Immune System Key Ltd, is a 14 amino acid modifed form of a novel human hormone-peptide, which was found to be a native ligand of the ST2 receptor and plays a pivotal role in immune system response. Nerofe is a derivative of the human hormone-peptide Tumor-Cells Apoptosis Factor (TCApF). TCApF binds to the T1/ST2 receptor and activates caspases 8, 9 and 3 mediated apoptosis, together with activation of JNKinase and p38 MAPKinase. Application of TCApF to cells induced apoptosis in acute myeloid leukemia proliferating cells (U937 premeyloid cells), in human breast carcinoma (MCF7), human glioblastoma, human neuroblastoma, human prostate cancer and human lung cancer proliferating cells. In contrast, TCApF was unable to induce apoptosis in non-proliferating cells. The selectivity of TCApF-induced apoptosis is related to the level of T1/ST2 receptor expression. Nerofe was granted by the FDA with orphan drug status for AML treatment and currently is in phase IIa development stage. Immune System Key Ltd holds 3 worldwide patents on the molecule and applications.

Fialuridine, or 1-(2-deoxy-2-fluoro-1-D-arabinofuranosyl)-5-iodouracil (FIAU) is a thymidine nucleoside analog with activity against various herpesviruses and hepatitis B virus (HBV) in vitro and in vivo. Herpes virus thymidine kinase considered to be a target of FIAU. In a Phase II study, fialuridine induced a severe toxic reaction in chronic hepatitis B patients characterized by hepatic failure, lactic acidosis, pancreatitis, neuropathy, and myopathy. These clinical manifestations led to the hypothesis that the toxicity of FIAU was mediated through mitochondrial dysfunction, possibly as a result of the inhibition of mitochondrial DNA polymerase gamma and/or incorporation of FIAU into mitochondrial DNA.