{"entity":{"id":"cdk46-inhibitor","kind":"technology","name":"CDK4/6 inhibitors","aka":[],"tldr":"Pills that stop the cell-division engine, added to hormone therapy for the most common type of breast cancer.","summary":"Palbociclib, ribociclib, abemaciclib with endocrine therapy: PFS roughly doubled and, for ribociclib and abemaciclib, overall survival improved in advanced HR+/HER2- disease. Ribociclib (NATALEE) and abemaciclib (monarchE) are approved as adjuvant therapy for high-risk early disease. 2026: palbociclib approved as maintenance in HR+/HER2+ disease (PATINA).","status":"approved","asOf":"2026-09-04","wikipedia":"https://en.wikipedia.org/wiki/CDK_inhibitor","links":[{"label":"Wikipedia","url":"https://en.wikipedia.org/wiki/CDK_inhibitor"}],"tags":[],"related":["oral-serd-plus-cdk46-after-esr1","cdk46-plus-endocrine"],"cancers":["breast-hr-positive"],"sections":["targeted-therapy","hormonal"],"technologies":[],"targets":["cdk4-6","estrogen-receptor"],"drugs":["palbociclib","ribociclib","abemaciclib"],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":["paper-sherr-roberts-cdk-inhibitors-genesdev-1999"],"journals":[],"dependsOn":[],"notes":[],"principle":"Block RB phosphorylation, arresting cells in G1.","strengths":["Oral, well tolerated","Adjuvant survival benefit"],"limitations":["Neutropenia, 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