[Becky]

There is no data on how they work in a primary condition versus each other in early bc. There was one paper I know of that tests the 3 against each other in bone mets (using only an AI and no chemo). Femara was slightly better but there were only 20 women in the study and the difference was not significant. They would need to test 100s to get significance. That said, I think that all three work equally as well and one has to chose depending on side effects. I am just going to switch because I want something that works differently (unless other data comes out between now and 2 years from now). Perhaps I will need to switch back to Arimidex as I am lucky to not have joint problems on it. The vaginal issues would happen regardless of the drug (and if they didn't, I would worry that the drug itself wasn't working as well for me as Arimidex as I would think I might have a bit more estrogen floating around).

I do believe that there is a trial comparing the 3 AIs head to head in early bc. My cousin is on the Arimidex arm. She is being encouraged to carry on when she wants to switch drugs due to joint pain.