The phase III trials for both Xtandi and Zytiga were similar. Both trials investigated men who progressed or died against placebo. Only 14% of men taking Xtandi during the trial progressed or died compared to 40% of the men in the placebo group. In the phase III trial of Zytiga 28% of the men progressed or died, compared with 46% on placebo. It appears that almost twice as many men died or progressed in the Zytiga group opposed to the Xtandi group.
These two trials were not head-to-head clinical trials, so any comparisons must be taken with a grain of salt.
Xtandi, unlike Zytiga it does not require the concurrent taking of Prednisone, a steroid that has side effects.
If your doctor suggests that you take Zytiga and prednisone instead of Xtandi ask, why.
Joel, Hogwash. NICE based its recommendation on price, Abiraterone’s makers would not cut the drug’s cost in the same way as Enzalutamide’s. They lost out. Nothing more to it than that.
You do understand why prednisone is included with Zytiga? And that the 5mg BID is only replacing endogenous amounts that are lost do to the inhibition of cyp17 which also inhibits the body’s natural production of cortisol. There is data available to provides a counter to your opinion. The additional P actually carries very little additional AE with the therapy.
Though I have been successful with Zytiga/abiraterone acetate, and possibly because despite becoming hormonal refractory my PSA level was still very low thus the cancer cells not aggressive in development, I have to agree with my friend Joel particularly if when becoming hormone refractory one’s PSA level is high or showing aggressive elevation. Probably Xtandi/enzalutamide the better medication for those men earlier diagnosed with high grade, high Gleason Score. I do continue to have the opinion that men diagnosed with lower grade lower Gleason Score becoming hormone refractory but with low PSA and slow PSA elevation that Zytiga continues to be a reasonable option. In my case, with my refractory cancer being very slow in growth and being successful in the blocking of testosterone production of testicular, adrenal glands, and that which cancer cells can produce themselves, Zytiga has proven a reasonable choice in managing/controlling my cancer for 54 months and counting with current PSA of 0.964ng/ml over that period of time. Xtandi/enzalutamide in my case is my considered future backup to my successful Zytiga.
What a journey. I cannot imagine doing this myself. You have my utmost respect. I am on Zytiga and Xtandi trial at the moment. Thank you for your input.
Michael, Your comments are all true, but my preference for enzaludamide is based much more on the survival data difference. The additional concern about the P is not my driving my opinion. Given the large number of drugs we need to take I, personally always prefer, if possible, to limit one or two if I am able. – Joel
I would lIke to add xtandi has a seizure warning while zytiga does not. Something to watch out for if you have a family history or high risk.
Also, Prednisone once started its pretty much for life
Ok so my husband is in flux between the two drugs. We have to make a decision ASAP. His PSA is rapidly rising last count was 9.2. Has PC in his bones but feels great! So far. The Zytiga has a cost of about &4500. We r researching the Xtandi but we think it will bill much less. He likes the no steroid but the seizure warning bothers me. HELP. NEED ADVICE…
Gail, did you ever get any advice as you asked?