Lilly inks $1.3 bil. RNA-editing deal with Rznomics to expand hearing loss pipeline 

Eli Lilly is adding to its growing genetic medicine portfolio through a licensing deal worth up to 1.9 trillion won ($1.36 billion) with Korea’s Rznomics to co-develop RNA-editing therapies for hereditary hearing loss.

Announced Thursday by Rznomics, the agreement includes an undisclosed upfront payment and royalties on future sales. Rznomics will lead early-stage research and development, while Lilly will take over for late-stage development and commercialization.

An Rznomics spokesperson told Korea Biomedical Review on Friday that the company is advancing multiple candidates in parallel rather than focusing on a single asset. “It depends on the specific gene mutations,” they said, “but we’ll be jointly selecting the most compatible targets for our platform.”

Lilly’s interest in the space isn’t new. In 2022, the company acquired Boston-based Akouos for $487 million, adding AK-OTOF, a dual adeno-associated virus (AAV) gene therapy designed to deliver a healthy copy of otoferlin, a gene commonly mutated in congenital hearing loss. That therapy made headlines early last year after restoring hearing in a child born deaf just 30 days after treatment.

But where Akouos delivers a full-length gene for durable expression, Rznomics is taking a different route. Its TSR platform, short for trans-splicing ribozyme, edits RNA rather than DNA.

TSR works by replacing faulty RNA transcripts with therapeutic ones, delivering a dual-function payload that removes and replaces in a single step. Rznomics says the platform can be tailored depending on therapeutic need, using adenovirus vectors for short-term effects like cancer treatment and AAV vectors for longer-acting or single-dose applications.

“Editing DNA has its advantages,” the Rznomics spokesperson said. “But if the correction doesn’t go exactly as intended, it’s very hard to reverse.” Because RNA is constantly produced in the body, they added, editing at the RNA level carries less risk and is generally safer since the effects are not permanent.

That safety profile is a key part of TSR’s pitch. The platform avoids foreign proteins like Cas enzymes, which the spokesperson noted can trigger immune responses and complicate delivery -- persistent limitations in many CRISPR-based approaches.

“Some of our optimized technologies are applied to our own drug candidates,” the spokesperson said. “But we believe the platform is versatile enough to support collaborative programs like this one targeting rare genetic diseases.”

Beyond hearing loss, Rznomics is advancing TSR in other areas, including rare diseases and oncology. Lead candidate RZ001 is in phase 1b/2a trials for hepatocellular carcinoma and glioblastoma in both Korea and the U.S. The company also received clinical trial clearance in Australia for a TSR-based gene therapy targeting retinitis pigmentosa, a genetic eye disease that causes progressive vision loss.