Xtandi and Zytiga Given Together - Advanced Prostate...

Advanced Prostate Cancer

22,391 members28,156 posts

Xtandi and Zytiga Given Together

RLSharp profile image
14 Replies

For those of you who are/were on Zytiga and Xtandi at the same time, I have a question. Were the doses and/or frequency adjusted to comply with the different metabolism rates of the two drugs when given together or were you treated with the standard doses of each drug? My Oncologist told me that he could not prescribe both drugs at the same time because they interact adversely because of their metabolism rates. I believe he said that the blood serum level of one goes up and one goes down. I do not remember which one went up and which one went down.

From the Full Prescribing Information under Drug Interactions for Xtandi and Zytiga is the following information.

From the Full Prescribing Information for Xtandi - Drug Interactions:

Avoid CYP3A4, CYP2C9 and CYP2C19 substrates with a narrow therapeutic index, as XTANDI may decrease the plasma exposures of these drugs.

From the Full Prescribing Information for Zytiga - Drug Interactions:

CYP3A4 Inducers: Avoid concomitant strong CYP3A4 inducers during ZYTIGA treatment. If a strong CYP3A4 inducer must be co-administered, increase the ZYTIGA dosing frequency.

CYP3A4 is also known as Cytochrome P450 3A4.

Richard

Written by
RLSharp profile image
RLSharp
To view profiles and participate in discussions please or .
Read more about...
14 Replies
Dan59 profile image
Dan59

I was on full dose of both after zytiga failed at 18 months , I added full dose xtandi to full dose zytiga and rode it for30 months. I did xtandi just before bed , and zytiga in morn

Dan

RLSharp profile image
RLSharp in reply toDan59

Thanks Dan. I did Xtandi for almost 2.5 years and it started to fail. Switched to Zytiga 6 months ago and it is failing. I will show your reply to my Oncologist on 2/15 and see if he will put me on both for a while. If not, it's docetaxel. The problem with docetaxel is I already have grade 3 peripheral neuropathy (reasons unknown) and it is possible that chemotherapy will make it much worse.

Richard

Dan59 profile image
Dan59 in reply toRLSharp

I used ice packs on bottoms of feet, and soaked fingers in ice water trying to prevent Nueropathy, It was mostly successful, there is actually a lot of post with information on this site on Nueropathy. When I did the combo xtandi zytiga, I had never done xtandi, Have you asked abouth increasing absorption of zytiga with food, Maybe ask the MO that question.

Neal-Snyder profile image
Neal-Snyder in reply toDan59

I'm being told to take things 1 at a time, to get the longest ride, & that the evidence isn't there yet from a completed clinical trial to show a survival advantage from combining. That's what I'm being told, anyway. Did your MO say there was research showing a benefit from taking the combo?

I got interested in taking Zytiga with food late in the almost 3 years I was on it, when my PSA began to rise. My MO tried to scare me off that by explaining that there was 5 times as much danger of liver damage. Then I spoke with another MO who thought I should try it. I compromised by decreasing the time between Zytiga & food in half-hour intervals & watching the safety test numbers stay good. But when I was ready to go from 1/2 hour to simultaneous is when we had to conclude that Zytiga has failed. Of course I wondered whether it would have worked longer if I'd tried simultaneous Zytiga & food sooner.

Dan59 profile image
Dan59 in reply toNeal-Snyder

I did zytiga first, then added xtandi to it after 18 months when zytiga alone strted to fail, after the combo started to fail I started eating with the zytiga and got more time. I like your idea of getting the longest ride. I sometimes think my long survival may be due to the many drugs I got a response from before xtandi and zytiga , such as time on ketoconazole, and estradiol. After developing resistance to these drugs I still got a response from zytiga and xtandi.

motosue profile image
motosue in reply toDan59

I was told not to take with food. So I wait till 2 or 3 AM to take it.

Dan59 profile image
Dan59 in reply toRLSharp

Keep us posted on what happens please. When I added xtandi to the zytiga,I had never done the xtandi , and the combo worked, at this point I want to rechallenge with xtandi, and they tell me it will not work. When I am out of options I will try it anyway with the blessing of my local MO.

Best wishes

Dan

afab profile image
afab in reply toDan59

Will do

motosue profile image
motosue in reply toRLSharp

Remember to put fingertips on ice cubes so to not increase neuropathy. I did that on my first infusion and don't have in my fingertips. Didn't do that on feet so I have neuropathy there. Hope that helps.

afab profile image
afab

RLSHARP/Richard, I’m in a clinical trial at Kaiser right now- one random Wing takes Xtandi and Lupron: the other Wing takes Xtandi, Lupron, Zytiga and pretnizone. I’m in the Xtandi and Lupron Wing. The two legs are being compared for effective ness.

You may want to get a second opinion.

Art

Neal-Snyder profile image
Neal-Snyder in reply toafab

Do you know how long it will be until the results are available?

motosue profile image
motosue in reply toafab

Please keep us posted on what happens. I am on Xtandi, Zytiga, prednisone, Lupron right now. Also interested in finding out if that combination hurts my liver or ????. Probably will take long to find out . :-(

Thanks afab.

afab profile image
afab in reply tomotosue

Will do.

afab profile image
afab

I don’t have a clue. I’m anxious to know

Not what you're looking for?

You may also like...

Eliquis and Xtandi - Drug Interaction

Dr. Corum called yesterday evening, said the pharmacist called, there was a drug interaction...
Hawk56 profile image

Zytiga (abiraterone acetate) vs Xtandi (Enzalutamide)

I remember Dr. Myers being cautious regarding Zytiga vs Xtandi. He said that he generally preferred...
cesanon profile image

Zytiga or Xtandi?

Next month, my husband will be started on a 2nd gen anti androgen. Are there any specific reasons...
leebeth profile image

Zytiga and Xtandi

I am not tolerating Zytiga well at the moment because of high blood pressure, irregular heartbeat...
Dastardly profile image

Next steps after Xtandi and Zytiga

I was diagnosed with mPC in May of 2016 at 59 years old. I’ve had Docetaxel, Lupron, Xtandi,...
tomtom9148 profile image

Moderation team

Bethishere profile image
BethishereAdministrator
Number6 profile image
Number6Administrator
Darryl profile image
DarrylPartner

Content on HealthUnlocked does not replace the relationship between you and doctors or other healthcare professionals nor the advice you receive from them.

Never delay seeking advice or dialling emergency services because of something that you have read on HealthUnlocked.