Arimidex or Femara?

[chrislmelb]

hi girls,
I am on arimidex (i persuaded my onc when all you girls were changing from Tamoxifen) and have been for about two years. I am also on Herceptin till November. As many of us know there are aches and pains etc etc associated with Arimidex and I am wondering if it is worthwhile giving Femara a go. I have a script form my onc to change (cos i asked for it) but i thought i'd run it past all of you first. Is Arimidex meant to be better with Herceptin? Is Femara just as good as Arimidex? I realise they are very similar but maybe the side effects will be better on Femara for me. Becky i know you are great with this stuff. Lani i try to read all your postings but i get a bit lost in it all.
Any help appreciated as i don't want to change over if it may be detrimental.
Thank you
Christine

[Becky]

Arimidex and Femara work in the same biochemical mechanism (to inhibit aromatase). Aromosin, the third AI, works in a different way to inhibit aromatase so many times, women will get the same side effects from Arimidex or Femara but not from Aromosin. That said, there are dozens on this board who switched from Arimidex to Femara (because of joint pain) and the switch was very worthwhile in that their pain was less or did not occur.

There is a huge trial that is ongoing testing the 3 AIs against each other in early breast cancer. By the time the trial is done, we will all be finished with our 5 years. In early bc, I don't think they will find a difference between the 3 drugs (with the exception of varying degrees of differing side effects).

However, in 2 different very small (less than 20 women) studies of women with bone mets, Femara worked better than the other 2 AIs but the difference wasn't statistically significant and trials with a larger population has to be used. Also, the researchers did not identify the pathology beyond being ER+ and PR+ women (don't know if they used any Her2+ women or not).

So - try Femara - all three drugs work well and you may not get the side effects you got from Arimidex. If Femara isn't better with the joint pain, or is worse, you can always try Aromosin or go back on Arimidex.

Cheers and Happy Mother's Day to all!

[chrislmelb]

Thanks for your prompt reply. I really appreciate it.
Happy Mothers Day to you too
Christine

[suzan w]

How long did you take Arimidex? I started Arimidex and Herceptin at the same time and the joint pain was so severe that I needed help to stand up. Did not know whether the pain was from the Arimidex, Herceptin or a combination of the two! Anyway...I decided to stick it out as my oncologist felt that there was a "slight" benefit for Arimidex over Femara...and within a few months the pain was almost gone. Funny thing though...the pain first started in my hips, then moved to my ankles...and has gone through just about every joint. Now it is in my shoulders...It has been 7 months since my last herceptin, and I have been taking Arimidex for 19 months and am pretty pain free. And days when I am stiff and sore an ibuprofin does the trick! Good luck!!!

[Jean]

Christine,

I was on Arimidex for one year. I had a great degree of bone and joint pain.
Esp. in the mornings could hardly move - but once I got going in the am
after exercise and walking it became less severe. But still had a great amount of joint pain neck, shoulders, ankles and hips. I did switch to Femara
and have been on it for 8 months. I am finding the Femara 75% better.
I have some muscle and joint stiffness but I work that out in the am.
But the bad pain is gone. Hope this helps.

Good Luck,
Jean

[chrislmelb]

Thanks for the replies Jean and Susan. Susan why did the onc say ARimidex might have a "slight" benefit?

[suzan w]

I don't know why she said that...but I will ask her for more specifics!