Ascidian Therapeutics entered a global research collaboration and licensing agreement with Eli Lilly to discover and develop therapies for monogenic kidney diseases, with an option to expand to additional targets.

The deal brings Ascidian's RNA exon editing platform together with Eli Lilly's genetic medicine expertise in an effort to address a category of inherited disease that has remained largely out of reach for existing therapeutic technologies.

What is RNA exon editing?

Ascidian's platform is built around the ability to rewrite RNA at the exon level, editing multiple whole exons at the kilobase scale to repair the faulty genetic instructions that drive disease.² The technology uses the cell's natural RNA splicing machinery to make those corrections without modifying the underlying genome or introducing foreign enzymes. According to Ascidian, the approach is designed to deliver the durability associated with gene therapy while substantially reducing the risks that come with direct DNA editing or gene replacement strategies.

That distinction is particularly meaningful in kidney disease, where many of the causative genes are large or exhibit high mutational variance, characteristics that have historically made them poor candidates for conventional gene editing tools.² Ascidian's exon editors were specifically developed to address those limitations, and the kidney represents an early and logical focus for deploying that capability.

"RNA exon editing gives us the ability to rewrite genes at their source, without altering DNA, opening the door to diseases long out of reach," said Michael Ehlers, MD, PhD, president and CEO of Ascidian Therapeutics. "Combined with Lilly's genetic medicine expertise, we aim to dramatically reduce the burden of genetic kidney disease."

What are the details of the deal?

Under the terms of the agreement, Eli Lilly is set to receives exclusive, target-specific rights to Ascidian's RNA exon editing technology for undisclosed kidney disease targets, while Ascidian will lead discovery and selected preclinical activities.¹ Eli Lilly will also assume responsibility for additional preclinical work, clinical development, manufacturing, and commercialization.

As part of the deal, Ascidian is eligible to receive up to $1.9 billion, including an upfront payment, development and commercial milestone payments, and tiered royalties on global sales.¹ Ascidian will also retain the right to independently pursue other kidney targets or partner with additional companies outside the scope of this agreement.

Why monogenic kidney disease?

The unmet need in monogenic kidney disease is substantial, as over 60 genetic diseases are known to affect the kidneys, and upwards of 3.5 million Americans currently live with severe inherited kidney disease.¹ Many of these conditions progress to kidney failure, requiring dialysis or transplant, yet no disease-modifying treatments exist for the majority of them. The genetic complexity of the diseases involved has long been a barrier to developing effective therapies, according to Ascidian.

Lilly has been expanding its presence in genetic medicines, and the collaboration with Ascidian reflects a broader industry shift toward RNA-based approaches as an alternative to permanent DNA modification. The option to expand the collaboration to additional targets beyond the initial kidney focus suggests both companies see this as a platform partnership with potential well beyond a single disease area.

"Lilly and Ascidian believe that patients with serious monogenic kidney diseases deserve effective treatment options and that an RNA-based approach is a compelling strategy for those diseases," Ehlers added.

Sources

1. Ascidian and Lilly Enter Global Research Collaboration to Develop RNA Exon Editors for Devastating Kidney Diseases Ascidian Therapeutics June 3, 2026 https://www.prnewswire.com/news-releases/ascidian-and-lilly-enter-global-research-collaboration-to-develop-rna-exon-editors-for-devastating-kidney-diseases-302789294.html
2. RNA exon editing: Splicing the way to treat human diseases National Library of Medicine August 16, 2024 https://pmc.ncbi.nlm.nih.gov/articles/PMC11401238/