TRI-611: A Brain-Penetrant Molecular Glue Takes Aim at ALK-Driven Lung Cancer
- TRI-611 is an orally dosed molecular glue degrader designed to eliminate ALK fusion proteins that drive a subset of non-small cell lung cancers.
- Rather than blocking ALK's active site like conventional inhibitors, it recruits the E3 ligase adaptor cereblon to a distinct surface on ALK, forming a complex that tags the protein for degradation.
- The molecule is reported to be highly selective, sparing other cereblon-dependent targets and unrelated kinases, and it degrades both wild-type and kinase-inhibitor-resistant ALK fusion variants.
- A central finding is brain penetrance: TRI-611 produced tumor regressions in intracranial as well as subcutaneous models, addressing CNS metastases that limit many existing ALK-targeted therapies.
- Degradation was rapid and long-lasting, and combining TRI-611 with standard ALK inhibitors produced more durable responses in preclinical models.
TRI-611 recruiting cereblon to a distinct, non-canonical surface on ALK — rather than working off the usual IMiD-derived degron — is the real chemistry story here; if that ternary interface holds up, it's a fresh template for kinases that don't glue easily. Wiping out kinase-inhibitor-resistant fusion variants is the killer selling point: degradation doesn't care about the affinity losses that gatekeeper/compound mutations inflict on ATP-competitive binders, so a mutant that's dead to a TKI can still form a productive ternary complex. Getting CNS exposure out of a CRBN glue is the harder chemical win — these scaffolds usually sit well outside Ro5, so brain penetrance without sacrificing ternary complex cooperativity argues for real optimization, not luck. Selectivity over other CRBN neosubstrates plus the TKI-combo data suggest this could slot in alongside inhibitors rather than just after them.
TRI-611, a selective, brain-penetrant molecular glue degrader of ALK ↗