This study is a single-arm, open-label, multicenter, phase II clinical study. Subjects were eligible for screening and entered the trial period after enrollment and received treatment with pyrotinib（320mg/day), trastuzumab(8 mg→6mg/every 3 week), dalpiciclib(125mg once daily for 3 weeks, followed by 1 week off in each 4-week cycle), endocrine therapy until disease progression, or intolerable toxicity, or withdrawal of informed consent, or discontinuation of medication at the investigator 's discretion. On-study imaging assessments were performed according to RECIST 1.1 criteria and the site assessment was final.
This study investigates the efficacy and safety of trastuzumab, pyrotinib combined with dalpiciclib and endocrine therapy for patients with advanced HR+/HER2+ brest cancer, providing more possible effective regimens for the survival benefit of these patients in clinical practice.