Hongene Expands exNA Technology Access for RNA Therapeutics Research with New Licensing Deal

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China-headquartered Hongene Biotech announced on Aug. 26, 2025 that it has entered into a non-exclusive licensing agreement with the University of Massachusetts Chan Medical School to produce and distribute extended nucleic acid (exNA) monomers and exNA-modified oligonucleotides for research applications. The collaboration aims to broaden the availability of an emerging oligonucleotide backbone modification that could significantly shape the future of RNA-based drug development (1).

The licensing deal reflects the ongoing demand for chemical innovations that improve the durability and delivery of nucleic acid therapies. By making exNA materials accessible to researchers, the agreement creates new opportunities for investigating therapies beyond the liver, a long-standing hurdle in RNA drug delivery (2).

“This partnership reflects our strategy to bring next-generation RNA chemistries to market and support researchers working on the toughest delivery challenges in oligonucleotide therapeutics,” said David Butler, PhD, chief technology officer at Hongene, in a company press release (1).

exNA chemistry and its role in drug development

The exNA modification was developed by scientists at the RNA Therapeutics Institute at UMass Chan Medical School. It introduces a proprietary structural change to the oligonucleotide backbone, designed to enhance stability and pharmacokinetics without disrupting established small interfering RNA (siRNA) designs (3).

Oligonucleotide developers have long pursued strategies to improve the persistence and tissue selectivity of RNA interference and antisense approaches. Backbone and sugar modifications—such as phosphorothioates, 2′-O modifications, locked nucleic acids (LNAs), and, more recently, exNA—are critical to extending half-life, reducing immunogenicity, and broadening tissue distribution (4). For drug developers, these modifications can mean reduced degradation rates, improved dosing regimens, and broader applicability across therapeutic areas.

The agreement will make exNA phosphoramidites and custom exNA oligonucleotides available through both catalog offerings and tailored synthesis services. By leveraging its experience in phosphoramidite manufacturing and oligonucleotide production, Hongene will act as a supplier for academic groups and biopharmaceutical companies looking to incorporate exNA into experimental platforms.

“By enabling access to exNA for research, we hope to accelerate the development of RNA-based medicines for extrahepatic indications,” said Butler in the release.

Implications for bio/pharmaceutical researchers

For researchers working on RNA interference, antisense oligonucleotides, clustered regularly interspaced short palindromic repeats guide design, and other modalities, the ability to source exNA building blocks through a commercial catalog could accelerate preclinical studies. The modification’s potential to improve extrahepatic delivery also addresses a technical barrier that has slowed therapeutic expansion beyond liver-targeted indications (2).

The broadened access to exNA may support the creation of more stable, tissue-specific RNA therapeutics, with implications for diseases that remain underserved by current modalities. For the bio/pharmaceutical industry, the availability of these tools underscores a growing emphasis on chemical precision and manufacturing scalability as critical enablers of RNA medicine (5).

References

1. Hongene Biotech. Hongene to Supply exNA Oligonucleotide Technology under New Licensing Deal. Press Release. Aug. 26, 2025.
2. Juliano, R. L. The delivery of therapeutic oligonucleotides. Nucleic Acids Research 2016, 44 (14), 6518–6548. DOI: 10.1093/nar/gkw236
3. Yamada, K.; Hariharan, V. N.; Caiazzi, J.; et al. Enhancing siRNA Efficacy In Vivo with Extended Nucleic Acid Backbones. Nat. Biotechnol. 2025, 43, 904–913. DOI: 10.1038/s41587-024-02336-7
4. Khvorova, A.; Watts, J. K. The Chemical Evolution of Oligonucleotide Therapies of Clinical Utility. Nat. Biotechnol. 2017, 35 (3), 238–248. DOI: 10.1038/nbt.3765
5. Roberts, T. C.; Langer, R.; Wood, M. J. A. Advances in Oligonucleotide Drug Delivery. Nat. Rev. Drug Discovery 2020, 19 (10), 673–694. DOI: 10.1038/s41573-020-0075-7