FEN-CRM + dmLT

FEN-CRM + dmLT is an investigational anti-fentanyl conjugate vaccine designed to prevent fentanyl from crossing the blood-brain barrier and exerting its psychoactive and respiratory depressant effects. The vaccine is composed of fentanyl (or a fentanyl analog) conjugated to a carrier protein (CRM197, a nontoxic mutant of diphtheria toxin), combined with the adjuvant dmLT (double mutant heat-labile toxin from Escherichia coli). The adjuvant enhances the immune response, promoting generation of high-affinity anti-fentanyl antibodies. These antibodies bind fentanyl in the bloodstream, preventing its entry into the brain, thereby attenuating both the rewarding and toxic effects of fentanyl. Preclinical studies (mice and rats) demonstrate the vaccine induces robust anti-fentanyl antibody titers, reduces fentanyl brain exposure, and blocks fentanyl-induced behavioral and physiological effects, including analgesia and respiratory depression. The strategy aims to provide immunotherapy against opioid use disorder and overdose, particularly for fentanyl and related analogs, with the CRM197-dmLT system selected for improved immunogenicity and safety relative to traditional vaccine adjuvants.

Other names

FEN-CRM + dmLTCRM-FEN + dmLTCRM197-glutaryl fentanyl plus dmLTCRM-197-glutaryl fentanyl plus dmLTCRM 197-glutaryl fentanyl plus dmLTanti-fentanyl vaccine