ideasIdea
Destroy the truncated androgen receptor that hormone drugs cannot touch
In advanced prostate cancer, a shortened form of the hormone receptor loses the very part existing drugs bind to. A drug that destroys the whole protein would still work.
AR-V7 lacks the ligand-binding domain, so enzalutamide and abiraterone cannot act on it, and its presence predicts resistance. Degraders and N-terminal-domain binders that engage full-length AR and its splice variants could restore control. Full-length AR degraders have reached the clinic; variant-competent agents are the unmet need, and AR-V7 status is already measurable in circulating tumour cells.
Hypothesis
An AR degrader or N-terminal-domain agent active against AR-V7 produces PSA responses in AR-V7-positive castration-resistant prostate cancer, where the response rate to further AR-pathway inhibition is near zero.
Rationale
AR-V7 is a well-defined, biomarker-selectable population with a mechanistically obvious unmet need; the degrader modality directly bypasses the missing ligand pocket.
What would test it
Phase 1b enriched for AR-V7-positive patients by circulating tumour cell assay, with PSA response rate and paired biopsy AR degradation as endpoints.
Maturity
preclinical evidence
Who has to act
industry
Cost to try
Medium ($1M to $50M)
Years to first evidence
5
Bottlenecks it attacks
- The undruggable drivers · The proteins that drive most cancers, such as MYC, mutant p53 and most RAS variants, still have no good drug.
- Acquired resistance to every therapy · Nearly every targeted therapy stops working within months to a few years as the tumour adapts.