F-15599 is a novel agonist with high selectivity and efficacy at serotonin 5-HT(1A) receptors. In signal transduction, electrophysiological and neurochemical tests, F-15599 preferentially activates post-synaptic 5-HT(1A)Rs in rat frontal cortex. Such a profile may translate to an improved profile of therapeutic activity for mood disorders. [(18)F]F-15599 is a radiofluorinated agonist presenting interesting characteristics for probing in vitro and in vivo the high-affinity states of the 5-HT(1A) receptors. The Rett Syndrome Research Trust awarded a grant to Neurolixis to advance F-15599 to clinical development.

Kifunensine is an immunoactive compound originally produced by Kitasatosporia kifunense, which displays competitive inhibition against immunosuppressive factor in tumor-bearing mice. Kifunensine has also been shown to be a potent inhibitor of the purified glycoprotein processing enzyme, mannosidase I (MAN1), specifically MAN1A1, MAN1A2, MAN1B1 and MAN1C1. Kifunensine inhibits human endoplasmic reticulum α-1,2-mannosidase I and Golgi Class I mannosidases IA, IB and IC with Ki values of 130 and 23 nM, respectively. Enzymes of this class are important factors for the biosynthesis of various types of N-linked oligosaccharide structures. Inhibition of these structures by kifunensine can interfere with cell-to-cell adhesion, targeting of lysosomal hydrolases to lysosomes, and clearance of asialoglycoproteins from the serum. Kifunensine is used to suppress Endoplasmic Reticulum-Associated Degradation (ERAD) via the inhibition of endoplasmic reticulum-associated mannosidase activity. Kifunensine has shown potential for treatment of sarcoglycanopathies and lysosomal storage disorders. Orphan designation (EU/3/11/906) was granted by the European Commission to Généthon, France, for kifunensine for the treatment of beta sarcoglycanopathy, but it was withdrawn later. Kifunensine’s use as a therapeutic is currently being researched in several conditions that benefit from its ability to inhibit mannosidase I.

U0126 is a highly selective inhibitor of both MEK1 and MEK2, a type of MAPK/ERK kinase. The inhibitory effects of U0126 on MEK and ERK activation have been confirmed repeatedly, and treatments with U0126 have been shown to inhibit proliferation and migration of cancer cells in vivo and in vitro. U0126 has been widely used as an inhibitor for the Ras/Raf/MEK/ERK signaling pathway. U0126 treatments lead to cancer cell death, which agrees with the well-known role of the Ras/Raf/MEK/ERK pathway in supporting cell survival. U0126 enhances apoptosis in human breast cancer MCF-7 cells, acute myeloid leukemia, and PC12 cells.

RG2833 is a compound originally developed by the Scripps Insitute for the treatment of Friedrick's Ataxia. RG2833 is a potent and selective inhibitor of neuronal histone deacetylase. RG2833 has been granted orphan drug status has been investigated in phase one clinical trials. There has also been proof of concept studies conducted for the treatment of Parkinson's disease.