Imexon is an iminopyrrolidone aziridine. It has anti-cancer activity.

Imexon induces single-stranded breaks in the human A375 melanoma cells but only obviously at the highest concentrations for each agent compared to controls. Imexon causes oxidative stress in the ER, activates an ER stress response. Imexon does not obviously alter the levels of eIF2B5, however, there is a dose-dependent increase in the phosphorylation of eIF2alpha, as well as an increase in the levels of GTP exchange protein eIF2B2 in MiaPaCa-2, Panc-1, and BxPC3 cells[1]. Imexon plus DTIC cytotoxicity is additive[2]. Imexon display inhibitory activities against MiaPaCa-2, Panc-1 and BxPC3, (IC50s: 275.5 ± 54.2, 147.4 ± 4.7 and 355.7 ± 114.7 μM).[3].

When administered at 100 mg/kg, Imexon demonstrates enhanced efficacy in suppressing Panc-1 tumor growth in SCID mice when used alongside GEM, evidencing a synergistic effect. Concurrently, pairing Imexon with DTIC elevates peak plasma levels of Imexon in mice without tumors. This drug duo also augments the plasma Imexon area under the curve (AUC) by 22% (p=0.026). Despite this, a regimen of Imexon (100 mg/kg/day, intravenously) leads to weight loss in SCID mice carrying human A375 melanoma tumors, without significantly impacting tumor progression[2].