Technology tamfitronics MainThe transcription factor nuclear factor E2-related factor 2 (NRF2) is an attractive therapeutic target because its activation stimulates a panoply of antioxidants that naturally resolve oxidative stress, a process central to diseases with great societal burden1,2,3,4. However, systemically distributed activators such as monomethyl fumarate (MMF) have global on-target actions because of the ubiquitous expression of NRF2 (refs. 2,3,5,6). In addition to activating NRF2 by modifying Kelch-like ECH-associated protein 1 (KEAP1) thiols (Cys151), MMF also exerts undesirable off-target actions by indiscriminately modifying other protein thiols as well3,4,5,6,7,8. We sought to overcome these dose-limiting and harmful side effects3,4,5,6,9,10 by creating a prodrug that would release MMF only when and where required.Hydrogen peroxide and peroxynitrite are...