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Advanced Prostate Cancer
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Rechallenge with Xtandi

I have been in this battle for almost six years (please see bio for complete treatment history).

Last chemo Docetaxel/Carboplatin chemo cycle was 1/9/18 and PSA had fallen from 10.8 to .4. While on my chemo break, PSA started to rise again, so about 2 1/2 weeks ago, we decided to give Xtandi a second chance.

I had taken Xtandi back in 2015-2016 after Zytiga failed and I got about 12 months run on Xtandi.

Wonder of wonders, rechallenge with Xtandi has dropped PSA from 1.3 to .7 after first 2 1/2 weeks! Hoping for a long run this second time.

Anyone out there been down this road?

Best wishes. Never Give In.

Mark, Atlanta

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I am just starting with Zytiga and happy to hear there is hope for continued success in this long fight. Best wishes for your continued success with Xtandi this second time around.

George

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Mark---my Geneticist has discussed this with me---that losing efficacy of Xtandi, or Zytiga--usually means that the AR-V7 gene splice is active---and that many times Chemo, has an ability to turn this gene splice variant off---so that the drugs above will work again. For how long---no data--I know one guy in California that was working on year 3.

Nalakrats

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Thank you for this hopeful info.

Mark

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I think BAT has a similar effect High T injections done every 28 days made ADT work again. Dr. Denmeade

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Can't help wondering whether alternating the chemo and xtandi indefinitely. Good luck. Rocco

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No Idea--we do not have enough studies---but individual cases where resensitizing can happen--my Geneticist--indicated that what little data she had---and thru her connection to Foundation Medicine, and the AR-V7 Gene Splice work of hers---suggested to me that about half of Men get a favorable response. That there is something in the Pathology, or underlying Neuroendrocrine Pca cells, advancing, and Pathology that is designated as highly undifferentiated, that may not allow resensitizing.

Nalakrats

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Antonarakis at Johns Hopkins observed this phenomenon in a small pilot study. Of 11 patients who had the AR-V7 variant that creates Zytiga/Xtandi resistance, 6 became non-resistant after taxane therapy, and 5 continued to be resistant. I hope a larger study will be conducted. They may be able one day to determine other factors that predict for resistance reversal.

academic.oup.com/annonc/art...

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Thank you for the link. I will keep this site updated as I move forward.

Mark

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i am happy for you. and I hope you have many years on Xtandi. You have tried to help other brothers. You are a good brother.

A member of the Reluctant Brotherhood,

Rich

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Thanks BigRich! This site is wonderful in that we can share our personal learnings and experiences with others in this battle. Together we fight.

Mark, Atlanta

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Mark, This is great news!This gives me great hope. As I had always planned was to rechallenge with all drugs that had worked in the past when chemo fails. As. Tall Allen posted below the response rate for rechallenge with xtandi after taxane is greater than 50%. I guess then we go back to taxane therapy and rechallenge again down the road. Thanks, I hope your response last a long time. We have to get as much out of our limited therapies as we can.

Dan

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Why didn't someone try this with Ray??? He was on Xtandi for 12 - maybe 18 months, then as he said, "things went south". I'm so very happy for any of you who are blessed enough to do a rechallenge with Xtandi. It just makes the widows/caregivers so sad and frustrated that this wasn't discovered sooner, say, like about 3 years ago. Pretty bitter-sweet . . . I certainly don't begrudge anyone for their great results, and definitely do not want to play the "sour grapes" card. Best of luck, all of you!

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