Lower dosing of abiraterone acetate in treatment of elderly prostate cancer patients

A group of Italian clinicians and researchers have reported that low-dose abiraterone acetate along with very low-dose prednisone appears to be both effective and safe in the treatment of elderly patients between 85 and 93 years of age with castration-resistant prostate cancer (CRPC).

The standard dose of abiraterone acetate (Zytiga) in the treatment of men with mCRPC is 1,000 mg (four 250 mg tablets) administered orally, once a day (on an empty stomach) along with predisone 5 mg taken twice daily. However, the current study examined a slightly reduced dose of abiraterone acetate (750 mg or three 250 mg tablets) administered orally with concomitant oral prednisone, 5 mg daily.

The study was a pilot initiative to see if elderly patients, at potentially greater risk of the side effects of abiraterone acetate and corticosteroid therapy (the prednisone), would respond well to lower doses of the two drugs. Here are the findings reported by Petrioli et al.:

  • 26 patients with a median age of 88 years (range, 85 to 93 years) were enrolled.
  • A PSA response was observed in 18/26 patients (69 percent).
  • Median time to PSA progression was 6.4 months.
  • Median overall survival was 14.3 months.
  • Treatment was well-tolerated and adverse events, related to mineralocorticoid excess, were of grade 1 or 2 in all patients.

The authors conclude that

Reduced dose of [abiraterone acetate] combined with a very low dose of prednisone is effective and well-tolerated in very elderly patients with advanced CRPC.

However, we already know that there is potential to give still lower doses of abiraterone acetate with food (as opposed to on an empty stomach) and to see similar or even better clinical impact. To that extent, the “best” way to actually treat patients (elderly or otherwise) with abiraterone acetate remains unresolved. It may well be that if one gives lower doses of abiraterone acetate along with food, one can also lower the requisite dose of prednisone too.

9 Responses

  1. Please tell my oncologist about this. I’m 85 and have been taking 100mg (without food) of the stuff daily for years. It’s the Prednisone that is killing me (splotchy skin, edema, puffy cheeks, etc.).

  2. Dear eCid:

    We are not in a position to “tell your oncologist” about this, but there is no reason why you shouldn’t do this yourself (and give him the link to the relevant information). And I suspect that you have been taking 1,000 mg of abiraterone acetate, not 100 mg.

  3. Yes, of course you can’t tell my oncologist. Just kidding. However, I can’t tell the oncologist either (oncologist is very defensive about treatment suggestions). Yes, I did mean 1,000 mg. In addition to splotchy skin, edema, puffy cheeks, I should have added that: any slight bump leads to bleeding and unsightly blots that take weeks to clear up, by which time I have new ones elsewhere. To be fair, oncologist has started Lupron shots again, and that may also be the cause.

  4. Hmmm … Maybe you need a different oncologist! :O)

  5. Or just to stop all medications and allow nature to take its course. Always an option … but at least, I’d make a better looking corpse without all the blotches.

  6. You may want to try less prednisone. I am taking just 5 mg once a day with breakfast at 7:30 after taking 1,000 mg of Zytiga at 5 a.m. … very few side effects. Recently added estrogen patches which seem to help with some of the side effects of the Lupron. (I am younger at age 58 and in good health.)

  7. Thanks for the tip. Interesting about the estrogen patches. Sorry to read that you have this problem at such a young age.

  8. Good job you’re doing, but I’d like to know if there is any study that can confirm reducing daily dose, let’s say to 500 mg. This dose probably given with a particular diet that can enhance absorption/bioavailability, while maintaining prednisolone levels to counter the adverse effects of the abiraterone. Thanks.

  9. Dear Mr. Nnaemeka:

    Several small studies have provided information that giving lower doses of abiraterone acetate (down to as low as 250 mg/day I believe) in conjunction with food and prednisone or prednisolone can indeed have activity in the management of advanced forms of prostate cancer. However, there has not yet been (as far as I am aware) any large, randomized clinical trial that can categorically confirm the effectiveness of this form of therapy.

    On the other hand, it is my understanding that there are at least some physicians who are advising their patients that abiraterone can be taken in this manner because of the significant potential cost savings.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: