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].

Imexon (100 mg/kg) in combination with GEM shows synergistic inhibition of Panc-1 tumor growth in SCID mice. Imexon in combination with DTIC results in an increase in the peak plasma imexon level in non-tumor-bearing mice. The combination of both drugs increases plasma imexon AUC by 22% (p=0.026). Imexon (100 mg/kg/day, i.v.) treatment decreases the body weight of SCID mice bearing human A375 melanoma tumors, but there is no significant difference in tumor growth[2].