I'm glad you brought up the CDK4K drug issue! I too am being steered by my Doc toward trying Verzenio. She would like to add a hormone blocker to it also, but after trying 2 AI's and Fulvestrant shots, and then a low dose of Tamoxifen, all of which gave me serious side effects like labile hypertension, very achy legs with a rash after 4 months resulting in some vein insufficiency, and severe headaches, I've decided Hormone blockers are not for me. I see that Verzenio is not a H-blocker, but "a targeted therapy known as a CDK4/6 inhibitor. While it treats hormone-receptor positive (HR+) breast cancer, it works by blocking proteins (CDK4 & 6) that fuel cancer cell division, rather than cutting off hormone production like hormonal therapies." I need to shrink a tumor, so may try it. Hopefully it can be adjusted for weight, because at 130 lbs. and age 76, I seem very sensitive to all meds. I don't want to feel sick and diarrhea-prone for summer, would rather go walking & do gardening, but need to shrink this in-my-chest-wall tumor recurrence from 30 years ago. Maybe follow up with Proton radiation if it shrinks. It's pretty hard to choose another sickening drug when the others gave me more trouble than I had.