Germany-based biotech Seamless Therapeutics and Eli Lilly and Co., entered into a global strategic research collaboration and licensing agreement to jointly develop programmable recombinase-based therapeutics targeting genetic forms of hearing loss. The deal will see Seamless apply its proprietary programmable recombinase platform to design site-specific gene editors, with Lilly granted exclusive license to resulting candidates in defined hearing loss indications.
Under the deal terms, Seamless will be responsible for designing and programming site-specific recombinases tailored to correct selected mutations associated with hearing loss. These programmable recombinases perform precise DNA insertions independent of the cell’s natural DNA repair pathways, a feature that distinguishes them from other editing technologies.
Lilly will take the lead on downstream activities, including preclinical validation, clinical development, regulatory submissions, and commercialization responsibilities for the licensed recombinase candidates. The collaboration focuses on multiple defined hearing loss targets, with platform activities centered on translating the underlying recombinase science into therapeutic assets.
Financial terms include an upfront payment and committed research funding to Seamless, and the company is eligible to receive total consideration above USD 1.12 billion, comprised of development and commercial milestone payments. In addition, Seamless may be eligible for tiered royalties on net sales of products successfully commercialized under the collaboration. Further specifics of the financial arrangements have not been disclosed.
The promise of programmable recombinase
For Seamless, the agreement represents a significant partnering milestone for its programmable recombinase platform. Programmable recombinase gene editing represents a next-generation approach to genome engineering, offering the potential for highly precise, large-scale DNA modifications without introducing double-strand breaks or relying on endogenous DNA repair pathways. This technology is distinct from CRISPR, TALENs, and zinc finger nucleases, and is rapidly gaining attention for its ability to perform targeted insertions, deletions, and inversions at user-specified genomic loci.
Lilly’s partnership with Seamless reflects broader industry interest in gene editing modalities that go beyond traditional CRISPR-associated nuclease systems. While Seamless has a specialist focus on the technology, there are several other biotechs involved in the space. These include Tome Biosciences, which offers the PASTE (Programmable Addition via Site-specific Targeting Elements) platform, originally developed at MIT; Prime Medicine, whose portfolio of platforms includes PASSIGE (Prime Assisted Site-Specific Integrase Gene Editing); and the France-based Brink Therapeutics, only founded in 2024, which uses Directed Evolution and Generative AI to screen billions of synthetic recombinase sequences and develop next-generation enzymes, principally for use in CAR-T cell therapies and complex cell engineering. In addition, multiple academic groups are developing bridge RNA-guided recombinase systems and zinc-finger/TALE recombinase fusions, still at the translational stage.