Xeloda is a very effective drug with a very good quality of life. It is very targeted to avoid healthy cells and activates in the liver and targets the cancer cells. It is also particularly effective on liver mets. People can remain on it for years. There is one woman on these boards now that has been taking it for over 4 years. I have heard there is a woman (not on these boards though) that has been taking it over 10 years. Many find it is more tolerable than hormone therapy and targeted therapies. I have found it to be the most tolerable drug I have taken to date (and it was also the most effective). Given it is in oral form, there is no need to go get a chemo infusion weekly or every few weeks. It does not cause hair loss, extreme weakness or heavy nausea/vomiting. The biggest side effect is hand-foot syndrome. All in all, a pretty good option. Many targeted therapies sound like they would be pretty tolerable but in fact produce some pretty harsh and/or risky side effects (Ibrance - serious infection risk due to low ANC, Afinitor/everolimus - serious pneumonitis/lung issues risk, painful mouth sores, TKIs - I took erdafitinib and it caused major liver toxicity requiring breaks from treatment and painful digestive issues). DS-8201 and SYD985 are not approved in the US at this point and are for HER2+ (or in the case of DS-8201, possibly HER2-low as well). TDM-1, Perjeta and Margetuximab would only be given to someone who is HER2+.

With exemestane, I think it came down to the fact exemestane was the drug that the makers of everolimus partnered with for the trial. They may have had the best co-marketing/trial sponsorship deal with the makers of exemestane. For the most part, the AIs can be used interchangably. For example, I was prescribed exemestane with Ibrance which is usually given with letrozole. I still haven't taken letrozole.