CounterX Therapeutics (Seattle, WA) has executed an exclusive licensing agreement with the University of Minnesota (Minneapolis, MN) and the University of Washington (Seattle, WA) covering a portfolio of monoclonal antibody and fentanyl vaccine candidates targeting synthetic opioid overdose, along with the company's proprietary CounterXCL™ platform technology (announcement). The deal grants CounterX exclusive rights to issued and pending patents developed by Marco Pravetoni, the company's founder and chief scientific officer, during his faculty appointments at both universities. The lead asset, CTRX-101, is a monoclonal antibody targeting fentanyl that the company plans to advance into a Phase 1 clinical trial in 2026.
Financial terms of the agreement were not disclosed. The announcement did not include details on upfront payments, development or commercial milestones, royalty rates, or equity components. The territorial scope of the exclusivity was not specified beyond the designation of the license as exclusive.
Deal context
CTRX-101 is a monoclonal antibody engineered to bind fentanyl and related synthetic opioids in the bloodstream, preventing the drug from crossing into the central nervous system and activating mu-opioid receptors. This opioid overdose antibody approach differs mechanistically from naloxone, the current standard of care, which acts as a short-acting opioid receptor antagonist requiring repeated dosing in cases involving potent synthetic opioids. CTRX-101 is formulated as a long-acting subcutaneous injectable and is not itself an opioid or controlled substance. According to the company, the monoclonal antibody fentanyl candidate was well tolerated in preclinical models with no serious adverse events when used alongside medications for opioid use disorder. The company has stated it does not expect CTRX-101 to cause opioid withdrawal. No IND filing has been confirmed, though the anticipated Phase 1 timeline in 2026 implies IND-enabling work is underway or nearing completion.
The licensed portfolio also includes fentanyl antibody therapeutics in the form of vaccine candidates designed to elicit endogenous antibodies against fentanyl and related synthetic opioids. These conjugate vaccines present opioid-like haptens on carrier proteins, with published research from Pravetoni's laboratory describing the use of TLR7/8 agonist adjuvants to enhance the immune response. The opioid vaccine development program remains at a preclinical stage, and no specific vaccine candidate names or clinical timelines were disclosed.