{"entity":{"id":"ribociclib","kind":"drug","name":"Ribociclib","aka":["Ribociclib Succinate and Letrozole","Kisqali Femara Co-Pack"],"tldr":"Ribociclib is the CDK4/6 inhibitor with the most consistent survival benefit, approved for a broad population of early breast cancer patients since 2024.","summary":"Ribociclib is a CDK4-biased CDK4/6 inhibitor given for 21 days of a 28-day cycle with an aromatase inhibitor or fulvestrant, at 600 mg daily in advanced disease or 400 mg daily for 3 years in the adjuvant setting. Its survival data are the most consistent in the class: MONALEESA-2, -3 and -7 each showed an overall survival benefit in HR-positive, HER2-negative advanced breast cancer, and NATALEE extended it to stage II-III early disease, including node-negative tumours, with an invasive disease-free survival HR of 0.75 (4-year iDFS 88.5% versus 83.6%), leading to adjuvant approval in September 2024. Novartis markets it. Neutropenia is near-universal (94%), and QT and liver enzymes need monitoring. Whether the adjuvant benefit matures into a survival gain remains open. For a newcomer: the CDK4/6 pill with the broadest proven benefit in hormone-driven breast cancer.","status":"approved","asOf":"2026-09-04","wikipedia":"https://en.wikipedia.org/wiki/Ribociclib","links":[{"label":"FDA label (DailyMed)","url":"https://dailymed.nlm.nih.gov/dailymed/search.cfm?query=Ribociclib"}],"tags":[],"related":[],"cancers":["breast-hr-positive","hr-positive-early-high-risk"],"sections":[],"technologies":["cdk46-inhibitor"],"targets":["cdk4-6"],"drugs":[],"companies":["novartis"],"institutions":[],"pathways":[],"terms":[],"trials":["natalee","nct06726148","nct05867251","nct05358249","nct04417621","nct05768139","nct06065748","nct07002177","nct05563220","nct07085767","nct06757634","nct04862663","nct05573555","nct06380751","nct07647328","nct07405801","nct05827081","nct06760637","nct07054190"],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"brand":"Kisqali","modality":"Small-molecule CDK4/6 inhibitor","mechanism":"CDK4-biased CDK4/6 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tamoxifen","source":"https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=aaeaef94-f3f5-4367-8ea2-b181d7be2da8"},"toxicity":[{"event":"Neutrophils decreased","anyGradePct":94,"grade3PlusPct":45,"source":"https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=aaeaef94-f3f5-4367-8ea2-b181d7be2da8","note":"NATALEE / MONALEESA-2"},{"event":"Leukocytes decreased","anyGradePct":95,"source":"https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=aaeaef94-f3f5-4367-8ea2-b181d7be2da8","note":"NATALEE / MONALEESA-2"},{"event":"Lymphocytes decreased","anyGradePct":97,"source":"https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=aaeaef94-f3f5-4367-8ea2-b181d7be2da8","note":"NATALEE / MONALEESA-2"},{"event":"Infections","anyGradePct":37,"source":"https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=aaeaef94-f3f5-4367-8ea2-b181d7be2da8","note":"NATALEE / MONALEESA-2"},{"event":"ALT/AST increased (grade 3-4)","grade3PlusPct":8,"source":"https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=aaeaef94-f3f5-4367-8ea2-b181d7be2da8","note":"8-11% across trials"},{"event":"Nausea","source":"https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=aaeaef94-f3f5-4367-8ea2-b181d7be2da8","note":"NATALEE / MONALEESA-2"},{"event":"Fatigue","source":"https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=aaeaef94-f3f5-4367-8ea2-b181d7be2da8","note":"NATALEE / MONALEESA-2"},{"event":"Diarrhoea","source":"https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=aaeaef94-f3f5-4367-8ea2-b181d7be2da8","note":"NATALEE / MONALEESA-2"},{"event":"QT prolongation","source":"https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=aaeaef94-f3f5-4367-8ea2-b181d7be2da8","note":"Concentration-dependent; ECG monitoring required"}],"access":[{"country":"US","reimbursement":"Medicare Part D (oral); commercial plans per formulary, often with prior authorisation","assistance":"https://www.novartis.com/us-en/patient-support","source":"https://www.cms.gov/medicare/payment/part-b-drugs/asp-pricing-files","asOf":"2026-09-06"},{"country":"UK","reimbursement":"NICE: recommended with aromatase inhibitor (TA496), fulvestrant (TA687), and adjuvant (2025)","source":"https://www.nice.org.uk/guidance/published?ngt=Technology%20appraisal%20guidance","asOf":"2026-09-06"}],"regulatoryEvents":[{"date":"2017-03-13","type":"approval","region":"US","note":"With aromatase inhibitor, HR+/HER2- advanced breast cancer (MONALEESA-2)","source":"https://www.fda.gov/drugs/resources-information-approved-drugs/oncology-cancer-hematologic-malignancies-approval-notifications"},{"date":"2018-07-18","type":"approval","region":"US","note":"Pre/perimenopausal women and with fulvestrant (MONALEESA-7/-3)","source":"https://www.fda.gov/drugs/resources-information-approved-drugs/oncology-cancer-hematologic-malignancies-approval-notifications"},{"date":"2024-09-17","type":"approval","region":"US","note":"Adjuvant stage II-III HR+/HER2- early breast cancer at high risk (NATALEE)","source":"https://www.fda.gov/drugs/resources-information-approved-drugs/oncology-cancer-hematologic-malignancies-approval-notifications"}]},"route":"/drugs/ribociclib/","neighbours":{"cancer":[{"id":"hr-positive-early-high-risk","kind":"cancer","name":"High-risk early HR-positive breast cancer","route":"/cancers/hr-positive-early-high-risk/"},{"id":"breast-hr-positive","kind":"cancer","name":"HR-positive / HER2-negative breast cancer","route":"/cancers/breast-hr-positive/"},{"id":"invasive-lobular-carcinoma","kind":"cancer","name":"Invasive lobular carcinoma of the breast","route":"/cancers/invasive-lobular-carcinoma/"},{"id":"male-breast-cancer","kind":"cancer","name":"Male breast cancer","route":"/cancers/male-breast-cancer/"}],"technology":[{"id":"cdk46-inhibitor","kind":"technology","name":"CDK4/6 inhibitors","route":"/technologies/cdk46-inhibitor/"}],"target":[{"id":"cdk4-6","kind":"target","name":"CDK4/6","route":"/targets/cdk4-6/"}],"company":[{"id":"novartis","kind":"company","name":"Novartis","route":"/companies/novartis/"},{"id":"olema-pharmaceuticals","kind":"company","name":"Olema Pharmaceuticals","route":"/companies/olema-pharmaceuticals/"},{"id":"solti","kind":"company","name":"SOLTI Cancer Research Group","route":"/companies/solti/"}],"trial":[{"id":"nct06188520","kind":"trial","name":"A First-in-human Dose Escalation and Expansion Study to Evaluate the Safety, and Tolerability of AZD8421 Alone or in Combination in Participants With ","route":"/trials/nct06188520/"},{"id":"nct07002177","kind":"trial","name":"A Phase Ib/II Study to Evaluate Multiple Combination Therapies of FWD1802 in Patients With ER+/HER2- 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(Vepdegestrant) When Given With Other Medicines in People With Advanced or Metastatic Breast Cancer (Sub-Study B)","route":"/trials/nct05573555/"}],"idea":[{"id":"idea-cdk4-selective-first-line","kind":"idea","name":"CDK4-selective inhibitors as the new first-line backbone","route":"/ideas/idea-cdk4-selective-first-line/"},{"id":"idea-fund-payer-funded-pragmatic-trials","kind":"idea","name":"Payers fund trials of cheaper, shorter or lower-dose versions of expensive treatments","route":"/ideas/idea-fund-payer-funded-pragmatic-trials/"}],"pathway":[{"id":"breast-cancer-signalling","kind":"pathway","name":"Breast cancer (KEGG map)","route":"/pathways/breast-cancer-signalling/"},{"id":"er-signaling","kind":"pathway","name":"Oestrogen receptor signalling","route":"/pathways/er-signaling/"},{"id":"p53-cell-cycle","kind":"pathway","name":"p53 / RB / cell-cycle checkpoint","route":"/pathways/p53-cell-cycle/"},{"id":"cell-cycle-engine-cdks","kind":"pathway","name":"The cell-cycle engine (cyclins & CDKs)","route":"/pathways/cell-cycle-engine-cdks/"}],"pairing":[{"id":"cdk46-plus-endocrine","kind":"pairing","name":"CDK4/6 inhibitor + endocrine therapy","route":"/pairings/cdk46-plus-endocrine/"}],"person":[{"id":"debu-tripathy","kind":"person","name":"Debu Tripathy","route":"/people/debu-tripathy/"},{"id":"dennis-slamon","kind":"person","name":"Dennis J. 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