FNV-23-B, an antiviral pharmaceutical, served as the "countermeasure" for FNV-23—more commonly known as the Gray Death—the devastating plague that afflicted the planet of Sedesia. The Galactic Empire also engineered this therapeutic, which featured minuscule FNV-23 particles encapsulated in a polysaccharide shell within each administration. Upon ingestion, it introduced a novel FNV-23 variant into the organism, necessitating subsequent administrations of the supposed "cure."