Zytiga and Xtandi - Post Chemo

I just completed 6 rounds of chemo (docetaxle) 3 weeks ago and I am attempting to understand the road map options for my next treatment steps (my results and lessons learned posted recently against other posts). I'll be meeting with my MO in a week and I know in advance he will want to talk about Zytiga and Xtandi. I have read some literature but still have questions.

As my signature shows, I am post RM (12/08), salvage radiation (7/12), bone scans mid 2016 showed limited bone mets in rib and backbone. Two MO's recommended the Lupron /Chemo protocol which I accepted. I had a psa reading of 35 on the day I began bicaludimide, one week later Lupron, one week later first chemo. After 3 weeks my psa was 0.

I've noted that studies show that mean time of psa progression is 10.2 months.

So post (and pre for that matter) chemo, Zytiga (Abiraterone)and Xtandi (Enzalutamide) are widely used.

Perhaps, the post chemo sequence is Zytiga first then Xtandi but this order does not seem universal.

My key question: Are these drugs administered at the time of no positive psa progression / psa is zero?

Moreover, what are other options you guys see out there or have experienced?

Gary

Zytiga or Xtandi are used when someone becomes castration resistant (rising PSA in spite of Lupron). Insurance won't cover its cost while your PSA is undetectable or not rising (unless you have a very clever medical oncologist). It is taken in addition to, not instead of, Lupron. If you can get one of them now somehow, that's great! There are clinical trials for earlier use. Great response to the chemo!