Clinical Research Directory

Inclusion Criteria: * Willing and able to comply with all scheduled visits, treatment plan, laboratory tests, lifestyle considerations (including contraception requirements), and other study procedures. * histological or cytological diagnosis of locally advanced or metastatic HR-positive/HER2-negative breast cancer * Disease progression following prior standard therapy and eligible for the assigned study cohort * Measurable or evaluable disease per RECIST v1.1 * Willingness to provide tumor tissue for biomarker analyses * Eastern Cooperative Oncology Group performance status of 0-1 * Negative serum or urine pregnancy test and agree to use highly effective contraception or maintain true abstinence. * Adequate organ function and bone marrow reserves (hematology, renal, and hepatic) Exclusion Criteria: * Untreated, symptomatic, or unstable brain metastases * Symptomatic visceral disease at risk of imminent life-threatening complications * Uncontrolled infection or significant concurrent medical conditions * Clinically significant cardiovascular disease or prolonged QT syndrome * Pregnancy or breastfeeding * Prior treatment with a KAT6-targeting agent * Recent anticancer therapy, radiotherapy, or major surgery * Use of prohibited concomitant medications, including strong CYP3A4 inhibitors or inducers, proton pump inhibitors, P-gp inhibitors or inducers, and breast cancer resistance protein inhibitors * Participation in another interventional clinical study * Any condition that would interfere with study participation or evaluation of study results