New AR-V7 Test at John Hopkins

From what I've read AR-V7 can be a fluid genetic variant. Some guys who are AR-V7 positive (and are Zytiga/Xtandi resistant), may become AR-V7 negative after a course of taxanes (Taxotere or Jevtana). Some guys who are AR-V7 negative become AR-V7 positive with prolonged advanced hormonal treatment. Some guys stay AR-V7 positive. Some guys stay AR-V7 negative. So my question is - how does one know whether one's AR-V7 status is permanent or subject to change? And since we don't know how to predict that, how does it benefit us to know our AR-V7 status at a given point in time?

Overriding any of this is the STAMPEDE study that proved that early use of Taxotere prolongs survival. So it seems to me that all men with adequate performance status who are diagnosed with mets should be treated with Taxotere. Taxotere works irrespective of AR-V7 status, and may switch one's AR-V7 status to negative. Therefore, knowing one's current AR-V7 status really doesn't help one to make a treatment decision until after Taxotere therapy and castrate resistance.

Afterwards, if one turns out to be AR-V7 positive, one can forgo the advanced hormonals, or one can try them for a while to see if they work. If deciding on a cost basis, Zytiga costs $8,000 per month, there's whatever co-pay/deductibles one has to pay on that vs. the $1,000 out of pocket for the AR-V7 test. It seems insurance companies/Medicare would want to cover it in certain situations.

- Allen

Post Edited (Tall Allen) : 3/22/2016 4:25:53 PM (GMT-6)

I find it strange that JH will only do the test for those who are CR, since there now is some use of Xtandi/Abi before that stage. Assuming that the $1000 covers their cost, why should JH limit use of the test--I doubt it is habit forming?
Thanks again to the Tall One--in several years I have accumulated hundreds of pages of notes in my PC file, I would guess half of them are from the postings of the Tall One.

Houseboy,
I see that you are Zytiga-resistant, but why do you say you are Taxotere-resistant? You seem to have gotten a very good response to the Taxotere. I bring this up because it seems that there's no reason why you can't do it again, or use Jevtana next time.

Have you tried taking Zytiga since you had Taxotere? You can become resistant to Zytiga (or Xtandi or both) without being AR-V7 positive. AR-V7 positive tells you they won't work, but AR-V7 negative doesn't tell you they will after you've developed resistance. I think the best way to know if they work now is to re-challenge with it.

- Allen

It depends on the cost and your insurance. Is it cheaper to pay for the test or the pills? The other interesting option is a clinical trial of ARN-509 which may be effective irrespective of AR-V7 status. I know several clinical trials will be starting over the next few months.

- Allen