Neratinib Combined With Fulvestrant and Eribulin in the Treatment ofHR+/HER2+ Advanced Breast Cancer

This study is a single-arm, exploratory clinical trial. Eligible patients with recurrent or metastatic breast cancer will be screened and enrolled after signing the informed consent form, and will receive neratinib combined with fulvestrant and eribulin until disease progression or intolerable toxicity occurs. During the treatment period, clinical tumor imaging assessments will be performed every 6 weeks (2 cycles) in accordance with RECIST v1.1; safety assessments will be conducted using NCI-CTCAE 5.0, and adverse events will be recorded throughout the study and within 30 days after the end of treatment (the recording period for serious adverse events or adverse events related to the drugs involved in this trial will be extended to 90 days after the end of treatment).