$LGND Ligand owns a royalty-backed model rather than a traditional drug-discovery cost structure, so the quality and duration of partnered assets are the main d

$LGND Ligand owns a royalty-backed model rather than a traditional drug-discovery cost structure, so the quality and duration of partnered assets are the main drivers. On September 22, Ligand said it acquired royalty and milestone rights tied to Santen's Ryjunea for $23 million upfront, adding a pe…