Eli Lilly struck a global research and licensing collaboration with Ascidian Therapeutics for RNA exon editing aimed at inherited kidney diseases. Under the deal, Lilly could pay up to $1.9 billion in upfront, development, regulatory, and commercial milestones, plus royalties, for exclusive rights to Ascidian’s platform for initial monogenic kidney targets. Ascidian’s approach edits RNA by replacing disease-causing exons through endogenous splicing machinery, avoiding permanent DNA changes. The technology is delivered via an AAV expressing the RNA exon editor, aiming to handle large genes or mutations spanning multiple exons. For biotech investors and developers, the agreement marks another high-value move into RNA editing as companies seek differentiated tools for genetic disease segments where conventional editing is constrained by payload size or mutation complexity.