Rio Pharmaceuticals

Rio Pharmaceuticals is a private biotechnology company developing positron emission tomography (PET) imaging tracers for neurological diseases. The company focuses on fluorine-18-labeled small-molecule radiotracers that quantify disease-relevant transporter biology in the central nervous system, with the goal of improving diagnosis, staging, and monitoring of neurodegenerative disorders. Its lead program, RP115, targets excitatory amino acid transporter 2 (EAAT2) and is being evaluated clinically in dementia, with company materials also indicating studies in amyotrophic lateral sclerosis. Beyond RP115, Rio has disclosed earlier-stage CNS imaging programs targeting serotonin transporter and norepinephrine transporter. The company appears to operate as a platform-style neuroimaging biotech centered on quantitative PET diagnostics rather than therapeutic drug commercialization.