Alloy Therapeutics Inc., a privately held biotechnology ecosystem company based in Boston, announced a collaboration and license agreement with Biogen Inc. (Nasdaq: BIIB) granting Biogen access to Alloy’s proprietary AntiClastic ASO platform for the discovery and development of antisense oligonucleotide therapeutics against multiple undisclosed targets. The collaboration extends a working relationship between the two companies that previously included Biogen’s use of Alloy’s AI-enabled transgenic mouse platform.
Under the deal terms, Alloy will receive an upfront payment, alongside milestone payments and tiered royalties on any products that emerge from the collaboration, with specifics not disclosed. The specific biological targets Biogen intends to pursue using the platform have not been named publicly. The deal is structured as a technology licensing arrangement. Biogen will apply the AntiClastic ASO platform across its own research and development infrastructure to advance antisense programs, with Alloy serving as the platform licensor rather than a co-developer of specific drug candidates.
Alloy’s AntiClastic ASO platform is designed to address two persistent limitations in conventional antisense oligonucleotide drug development: insufficient potency at tolerable doses and a narrow therapeutic index. The AntiClastic platform is based on technology invented by antisense pioneer Sudhir Agrawal and licensed to Alloy through Arnay Sciences, combining sequence modifications with altered oligonucleotide conformation to improve potency and therapeutic index. This three-dimensional architecture is intended to improve binding affinity to target messenger RNA, reduce off-target hybridization events that contribute to hepatotoxicity and nephrotoxicity, and widen the gap between efficacious and toxic doses. Drug candidates generated using the platform have demonstrated increased potency relative to conventional gapmer antisense formats, according to Alloy. Partners may apply the AntiClastic format to existing antisense sequences or engage Alloy to discover new molecules against selected targets.
The ASO drug discovery field has seen validated clinical proof-of-concept through approved agents including nusinersen for spinal muscular atrophy and tofersen for ALS-associated SOD1 mutations, among others. Despite this validation, toxicity has remained a limiting factor in expanding the modality to broader target sets, particularly in neurological indications where intrathecal delivery concentrates drug exposure in sensitive tissue compartments. Biogen’s research focus is centered on neurological and neurodegenerative diseases, areas where ASOs have a delivery advantage over other modalities but where the therapeutic index challenge is correspondingly acute.
This transaction represents the second known collaboration between Alloy and Biogen. The prior engagement involved Biogen’s use of Alloy’s AI-enabled transgenic mouse platform, a separate technology within Alloy’s broader drug discovery ecosystem.