Enzalutamide (Xtandi) vs Abiraterone (Zytiga) for mHSPCA

[6357axbz]

Good trial results for both of these for mHSPCa, combined with ADT. Anyone here know the pros/cons? Which has better pfs and os? Thanks.

Randall

[CantChoose]

I've actually been wondering the same thing. Asking our MO this question tomorrow. Seems like Xtandi causes greater fatigue.

[tango65]

I believe the trial with enza is still going on:

ascopost.com/issues/april-1...

My understanding is that enza is approved for non metastatic and metastatic castration resistant cancer only.

[Break60]

What’s the point of adding tx if one is castrate sensitive with low PSA indicating no mets?

[6357axbz in reply to Break60]

The addition of enzalutamide (Xtandi) to androgen deprivation therapy (ADT) significantly prolonged radiographic progression-free survival (rPFS) compared with ADT alone in men with metastatic hormone-sensitive prostate cancer (mHSPC), according to findings from the phase III ARCHES trial.

At a median follow-up of 14.4 months, median rPFS was not reached in the enzalutamide arm and was 19.45 months in the placebo arm, indicating a 61% reduction in risk of radiographic progression or death with enzalutamide (HR, 0.39; 95% CI, 0.30-0.50; P <.0001),1 reported Andrew J. Armstrong, MD, at the 2019 Genitourinary Cancers Symposium.

[Break60 in reply to 6357axbz]

So if I had bone mets and no longer have them am I still considered metastatic?

[6357axbz in reply to Break60]

How do you know you no longer have bone Mets?

[Break60 in reply to 6357axbz]

Good question. I assume that if Psa is only .172 and declining that I don’t have bone mets. My last bone density scan was normal. And I’ve had bone mets radiated. No scan that I know of would be able to see bone mets at this low PSA. If I had the SOC bone scan it sure wouldn’t find any nor likely would the new ct pet scans.

[6357axbz in reply to Break60]

Never mind, I just read your history. I can’t answer your question as to whether or not you’re still considered metastatic.

[Magnus1964]

I have been in trials for both. Zytiga + low dose prednisone, 5mg to replace what zytiga takes out of you. I had no problems with this trial. By the way i am metastatic pre chemotherapy. I was on this trial for 3 1/2 years before it failed.

I am currently on an xtandi trial with a mystery drug from Eli Lilly which is supposed to extend the effectiveness of xtandi. I have now been on this trial for 3 years with no side effects. The only side effect has been gas. I am chewing GasX tablets like candy.

[Break60 in reply to Magnus1964]

Did you continue to be deemed metastatic ( and where were the mets )even after initial treatments before going on the Zytiga and xtandi trials? What treatments have you had and when?

Thx

Bob

[Magnus1964 in reply to Break60]

Any time the cancer leaves the prostate it is considered to be metastatic. Between these trials I was on Provenge for mets in the lungs. The nodules shrank and have remained so since. Mostly I have been treated for a rising PSA, no detectable mets.

[Break60 in reply to Magnus1964]

Ok so you’ve been treating mets due to rising Psa correct? If you’re Psa was low and falling and you had no detectable mets would you still have qualified for the abi and Enzo trials?

[Magnus1964]

If I remember correctly before each of these trials I had to have 3 consecutive rises in PSA.

[tango65]

Here is the final result of the abiraterone trial for mHSPC. The median for overall survival was 53 months.

thelancet.com/journals/lano...

[6357axbz in reply to tango65]

Thanks

[rococo]

Good os Stu, hope for the same with standing which I think offered 40 mo PCs. Still not which is best. Rocco