C9orf72 hexanucleotide repeat expansion is the most common genetic cause of both amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), accounting for approximately 30-40% of familial ALS cases and 20-25% of familial FTD cases. This investment landscape summarizes therapeutic approaches targeting C9orf72 pathology, including antisense oligonucleotides (ASOs), small molecules, and gene therapy strategies. The field has advanced significantly with multiple clinical-stage programs and a robust preclinical pipeline targeting the three main pathological mechanisms: loss of function, RNA foci formation, and dipeptide repeat protein (DPR) toxicity. [1]
This page summarizes R&D investment signals for C9orf72-targeted therapeutics in ALS and FTD. The C9orf72 gene encodes a DENN domain protein involved in endolysosomal trafficking and autophagy, and its expansion leads to both loss-of-function and gain-of-toxicity mechanisms. Therapeutic development focuses on: (1) reducing toxic RNA foci and DPRs; (2) restoring C9orf72 protein function; (3) addressing downstream effects including nucleocytoplasmic transport defects and mitochondrial dysfunction. [2]
| Program | Sponsor | Phase | Modality | Status | [3]
|---|---|---|---|---| [4]
| BIIB078 (ASO) | Biogen/Ionis | Phase 1/2 | Antisense Oligonucleotide | Completed |
| WVE-004 | Wave Life Sciences | Phase 1/2 | Antisense Oligonucleotide | Completed |
| ATNX-08045 | Accererant | Phase 1 | Antisense Oligonucleotide | Completed |
| Program | Sponsor | Modality | Target |
|---|---|---|---|
| Multiple programs | Various | Small molecule | DPR aggregation inhibitors |
| Various | Academic consortia | Gene therapy | Viral vector delivery |
| Several programs | Biotech startups | RNA-targeting | RNA splicing modulators |
ASOs target the C9orf72 pre-mRNA to reduce the production of toxic dipeptide repeat proteins while preserving normal C9orf72 expression. Key programs include:
Small molecules offer oral bioavailability and potential for combination therapy:
The C9orf72 therapeutic space is less crowded than other ALS targets (e.g., SOD1), offering potential first-mover advantages. Key competitors include:
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Renton et al. Neuron (2011). 2011. ↩︎
Miller et al. Nature Reviews Neurology (2020). 2020. ↩︎
Liu et al. Science Translational Medicine (2021). 2021. ↩︎