biostudies-literatureBaird RDNIHR Cambridge Biomedical Research Centre (NIHR Cambridge BRC)NIHR Cambridge Biomedical Research CentreAstraZeneca (AstraZeneca PLC)AstraZenecaCancer Research UK Cambridge CentreCambridge Experimental Cancer Medicine Centre4244-4254https://www.ebi.ac.uk/biostudies/studies/S-EPMC12521909biostudies-literatureUnknown31(20)<h4>Purpose</h4>This trial investigated the safety and tolerability of camizestrant with cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) in women with estrogen receptor-positive, HER2- advanced breast cancer.<h4>Patients and methods</h4>SERENA-1 (NCT03616587) is a phase I, multipart, open-label study in women with refractory estrogen receptor-positive, HER2- advanced breast cancer. Patients received oral once-daily camizestrant 75 or 150 mg plus abemaciclib; camizestrant 75, 150, or 300 mg plus palbociclib; or camizestrant 75 mg plus ribociclib 400 or 600 mg. Safety/tolerability, pharmacokinetics, efficacy, and impact on estrogen receptor 1 mutation ctDNA were assessed.<h4>Results</h4>By September 16, 2024 (data cutoff), 53 patients had received camizestrant plus abemaciclib, 78 camizestrClinical cancer research : an official journal of the American Association for Cancer ResearchCamizestrant in Combination with Three Globally Approved CDK4/6 Inhibitors in Women with ER+, HER2- Advanced Breast Cancer: Results from SERENA-1.PMC12521909BRC-1215-20014Yang JCiardullo CMorrow CJIncorvati JMoreno IHamilton EMathewson AMSykes ABermejo de Las Heras BLindemann JPOVictoria IArmstrong ARuiz-Borrego MCiruelos ETwelves CKabos POliveira MPatel MRKlinowska TTurner NBaird RDVaklavas CZhang BfalseCamizestrant in Combination with Three Globally Approved CDK4/6 Inhibitors in Women with ER+, HER2- Advanced Breast Cancer: Results from SERENA-1.<h4>Purpose</h4>This trial investigated the safety and tolerability of camizestrant with cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) in women with estrogen receptor-positive, HER2- advanced breast cancer.<h4>Patients and methods</h4>SERENA-1 (NCT03616587) is a phase I, multipart, open-label study in women with refractory estrogen receptor-positive, HER2- advanced breast cancer. Patients received oral once-daily camizestrant 75 or 150 mg plus abemaciclib; camizestrant 75, 150, or 300 mg plus palbociclib; or camizestrant 75 mg plus ribociclib 400 or 600 mg. Safety/tolerability, pharmacokinetics, efficacy, and impact on estrogen receptor 1 mutation ctDNA were assessed.<h4>Results</h4>By September 16, 2024 (data cutoff), 53 patients had received camizestrant plus abemaciclib, 78 camizestr2025-01-01T00:00:00Z2025 Oct2026-06-04T13:07:41.726Z2026-05-09T03:11:34.35ZS-EPMC125219094078818710.1158/1078-0432.CCR-25-1198