Study Evaluating Hemay022 In Subjects With HER2-Positive Advanced Breast Cancer

The purposes of this study are to assess the safety, tolerability and pharmacokinetics of Hemay022. The secondary purpose of this study is to assess the efficacy of Hemay022 in the treatment of HER2-positive advanced breast cancer. The study will be conducted in two parts. Part one, trial will be conducted in 18-30 subjects to determine safety and tolerability of Hemay022 in patients with HER2-positive advanced breast cancer. Part two, approximately 27 additional subjects with HER2-positive advanced breast cancer, are included to better define the tolerability and preliminary efficacy of Hemay022.