Three-mechanism combo memo: Fasudil + ARGX-119-like + CDDO-Me as the next SMA conversation
The thesis
Fasudil alone is a single-mechanism cytoskeletal rescue. The 2026 SMA Congress (Budapest) and the Cure SMA 2025 meeting together handed the field two orthogonal axes the community has not yet integrated into a combination framework:
- NMJ-directed rescue — first-in-class MuSK agonist Fabs (exemplified by ARGX-119 from argenx, O28 Budapest 2026)
- Redox rescue — omaveloxolone (Skyclarys, FDA-approved 2023 for Friedreich ataxia) + bardoxolone methyl (O16 Budapest 2026, NRF2/KEAP1 in SMA liver)
A rational 3-mechanism combo (ROCK inhibitor + MuSK agonist + NRF2 activator) covers the three major failure modes of SMA motor units — cytoskeletal collapse, denervation, and oxidative stress — simultaneously.
| Mechanism | Drug | Target | Status |
|---|---|---|---|
| Cytoskeletal rescue | Fasudil | ROCK2 → LIMK2 → CFL2 | Off-patent generic, CNS-penetrant |
| NMJ stabilisation | MuSK agonist Fab or salbutamol as small-molecule bridge | MuSK kinase (agrin-LRP4-MuSK-DOK7 axis) | Phase 1 complete for argenx ARGX-119 |
| Redox rescue | Omaveloxolone (Skyclarys) or CDDO-Me | KEAP1 Kelch → NRF2 nuclear translocation | Approved (Friedreich 2023) |
None of these requires new chemical matter. The novelty is in the combination framework, the mechanistic claim that these cover orthogonal failure modes, and the compute scaffolding to score each component for BBB penetration, pharmacokinetic compatibility, and off-target liabilities.
Full memo
Private memo held with collaborators. Platform summary below.
What we are running this week
- DiffDock + 100 ns MD on the NMJ axis (MuSK, LRP4, DOK7, AGRN, RAPSN) against ~20 compounds
- DiffDock + 100 ns MD on the NRF2/KEAP1 Kelch domain against 10 activators + 2 negative controls
- Pharmacokinetic compatibility modelling for the 3-mechanism combo in our digital twin
Open scientific questions
- Do NMJ + NRF2 + ROCK really cover orthogonal failure modes in SMA, or do they collapse onto the same pathway?
- At what dose ratios does the combo produce the strongest effect without PK interference?
- How does the combo interact with SMN-restoring therapy (nusinersen / risdiplam / onasemnogene abeparvovec)?