# AR-V7 splice variant

Source: https://onco.cc/terms/ar-v7/  
OnCo record `ar-v7` (Term). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

A truncated form of the androgen receptor that is permanently switched on and ignores hormone-blocking pills.

## Summary

AR-V7 is a truncated splice variant of the androgen receptor that lacks the ligand-binding domain, so it is permanently active and cannot be switched off by hormone-blocking drugs. It is detected in circulating tumour cells, for example by the Epic Sciences nuclear AR-V7 test, and its presence is associated with resistance to abiraterone and enzalutamide while taxane sensitivity is preserved, which makes it a candidate for guiding the choice between those classes. Readers meet it under castration-resistant prostate cancer, in the androgen receptor signalling pathway, the RNA splicing and transcriptional addiction pathways, and on the resistance-routes map. It is the rationale for N-terminal domain inhibitors such as masofaniten, which failed, and for androgen receptor degraders.

## Fields

- Kind: Term
- Last checked: 2026-09-06
- Also known as: androgen receptor splice variant; androgen receptor splice variant 7; AR splice variant; AR-V7 positive; AR variant; AR-V9; AR-V567es; truncated androgen receptor

## Notes

- Why a splice variant defeats a drug, in one sentence. Alternative splicing of the androgen receptor transcript produces truncated receptors, of which AR-V7 is the commonest and best studied, that retain the DNA-binding domain but lack the ligand-binding domain; they are constitutively active, and enzalutamide and abiraterone both act on the ligand-binding domain that is no longer there. AR-V9 and AR-V567es are other described variants, less well characterised clinically.
- The original figures, with their cohort. In 62 men with metastatic castration-resistant prostate cancer starting enzalutamide or abiraterone, AR-V7 messenger RNA was detectable in circulating tumour cells in 39 percent of 31 enzalutamide-treated and 19 percent of 31 abiraterone-treated men. Prostate-specific antigen response was 0 percent in AR-V7-positive men against 53 percent (enzalutamide) and 68 percent (abiraterone) in AR-V7-negative men; median prostate-specific antigen progression-free survival on enzalutamide was 1.4 against 6.0 months and overall survival 5.5 months against not reached.
- Why the test is available and little used. A negative result does not predict response, only the absence of this one resistance mechanism, and most non-responders are AR-V7-negative. Messenger RNA and protein-based assays do not identify the same men and the test is not standardised between laboratories. And the treatments a positive result would send a man to, taxanes and radioligand therapy, tend to be given in that sequence anyway.

## Sources

- Wikipedia: https://en.wikipedia.org/wiki/Androgen_receptor#Splice_variants
- Wikipedia: https://en.wikipedia.org/wiki/Androgen_receptor#Splice_variants
- Antonarakis et al., New England Journal of Medicine 2014: AR-V7 and resistance to enzalutamide and abiraterone in prostate cancer: https://doi.org/10.1056/nejmoa1315815

## Connected records

- terms: [Bipolar androgen therapy (BAT)](https://onco.cc/terms/bipolar-androgen-therapy/), [Castration-resistant prostate cancer (CRPC)](https://onco.cc/terms/castration-resistance/), [Genome-wide loss of heterozygosity (gLOH)](https://onco.cc/terms/genome-wide-loss-of-heterozygosity/), [Neuroendocrine differentiation in prostate cancer](https://onco.cc/terms/neuroendocrine-differentiation/), [Prostate cancer programmes that failed, and what each failure taught](https://onco.cc/terms/prostate-failed-programmes/)
- key papers: [AR-V7 and resistance to enzalutamide and abiraterone in prostate cancer](https://onco.cc/key-papers/paper-antonarakis-ar-v7-resistance-nejm-2014/), [Nuclear-localised androgen receptor splice variant 7 in circulating tumour cells as a predictive biomarker in castration-resistant prostate cancer](https://onco.cc/key-papers/paper-scher-nuclear-arv7-taxane-vs-arsi-jama-oncol-2018/), [PROPHECY: prospective multicentre validation of androgen receptor splice variant 7 and hormone therapy resistance in high-risk castration-resistant prostate cancer](https://onco.cc/key-papers/paper-prophecy-arv7-validation-jco-2019/)
- cancers: [Metastatic castration-resistant prostate cancer](https://onco.cc/cancers/prostate-mcrpc/), [Non-metastatic castration-resistant prostate cancer](https://onco.cc/cancers/prostate-nmcrpc/), [Prostate cancer](https://onco.cc/cancers/prostate/)
- targets: [Androgen receptor](https://onco.cc/targets/androgen-receptor/)
- pathways: [Androgen receptor signalling](https://onco.cc/pathways/ar-signaling/), [Resistance routes: how a blocked pathway comes back](https://onco.cc/pathways/resistance-routes-map/), [RNA splicing](https://onco.cc/pathways/rna-splicing/), [Transcriptional machinery & addiction](https://onco.cc/pathways/transcription-addiction/)
- drugs: [Galeterone](https://onco.cc/drugs/galeterone/), [Masofaniten](https://onco.cc/drugs/masofaniten/)
- trials: [ARMOR3-SV](https://onco.cc/trials/armor3-sv/), [CARD](https://onco.cc/trials/card/)
- biomarkers: [AR-V7 splice variant](https://onco.cc/biomarkers/ar-v7-splice-variant/)
- technologies: [CellSearch circulating tumour cell count](https://onco.cc/technologies/cellsearch-ctc-count/), [Parsortix label-free circulating tumour cell harvest](https://onco.cc/technologies/parsortix-ctc-harvest/)

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JSON: https://onco.cc/api/v1/entities/ar-v7.json