Overview

• Researchers report in PNAS that the molecule RcoM-HBD-CCC reduced the half-clearance time of carbon monoxide in blood to under one minute in mice, compared with more than an hour on 100% oxygen.
• Stopped‑flow spectroscopy showed the engineered protein binds CO about 50 times more tightly than hemoglobin, supporting rapid sequestration from red blood cells.
• In preclinical infusions, the therapy produced only minimal changes in blood pressure, avoiding the nitric‑oxide scavenging–linked hypertension that has hindered prior hemoprotein approaches.
• The CO-bound protein was eliminated via urine in animal studies, indicating a potential clearance route after treatment.
• The team plans additional dose-ranging and safety work, scale-up of recombinant production, and preparatory steps toward phase I trials with an eye to eventual use by first responders.