Efficacy and Safety of Dalpiciclib Combined with Anti-HER2 Targeted Therapy and Endocrine Therapy as First-line Maintenance Treatment for Patients with Recurrent or Metastatic Hormone-Receptor-Positive, HER2-positive Breast Cancer.
Females aged 18 to 75 years with pathologically confirmed metastatic or locally advanced unresectable breast cancer.
Hormone receptor (HR)-positive and HER2-positive.
Patients with no evidence of disease progression (including CR, PR, or SD)after 4-8 cycles of first-line systemic anti-tumor therapy.
ECOG Performance Status: 0-1.
Symptomatic active brain metastases or extensive leptomeningeal metastases.
History of Grade 3 or 4 allergic reaction related to the study drugs.
Currently receiving other anti-tumor therapies.