Breast Cancer: Targets and Therapy (May 2024)
Retrospective Analysis of Pyrotinib-Based Therapy for Metastatic Breast Cancer: Promising Efficacy in Combination with Trastuzumab
Abstract
Qingqing Gu, Mingzhi Zhu, Yanyan Wang, Yuanting Gu The Second Department of Breast Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, People’s Republic of ChinaCorrespondence: Yuanting Gu; Yanyan Wang, The Second Department of Breast Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, People’s Republic of China, Tel +86-371-66913114, Fax +86-371-66964992, Email [email protected]; [email protected]: To evaluate the efficacy and safety of a pyrotinib-based therapy for human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC) in the real world.Methods: Clinical data of 218 patients with HER2-positive MBC who received a pyrotinib-based therapy from January 2020 to March 2023 at the First Affiliated Hospital of Zhengzhou University were retrospectively analyzed.Results: Finally, 195 patients were included in the efficacy cohort. The median progression-free survival (PFS) in the total population is 12.4 months (95% CI, 9.8– 15.0 months). More than half of the patients in the efficacy cohort received pyrotinib mono-targeted therapy (103 cases, 52.8%). Among the remaining patients, 74 (37.9%) patients chose a combined trastuzumab-targeted therapy and 17 (8.7%) chose to combine inetetamab. Median PFS in the pyrotinib group vs pyrotinib plus trastuzumab group was 10.5 months vs 20.1 months (P< 0.001). The median PFS of primary trastuzumab resistance population reached to 20.1 months in pyrotinib plus trastuzumab group. Double-targets’ advantage was also observed in the brain metastases subgroup (17.9 months vs 10.0 months, P=0.386). The patients who received pyrotinib plus inetetamab as second and higher-line treatment reached a median PFS of 7.9 months (95% CI, 4.0– 11.8 months). Forty-one (19.8%) of 207 patients included in the safety cohort experienced grade 3 or higher diarrhea, the most common adverse event in safety analysis, and no adverse event-related deaths.Conclusion: The combination of pyrotinib and trastuzumab demonstrated promising efficacy in the treatment of HER2-positive metastatic breast cancer, including those who had primary resistance to trastuzumab and brain metastases. Pyrotinib plus trastuzumab is expected to be a potent option in the first-line. Additionally, the concurrent administration of pyrotinib and inetetamab could be an alternative to consider in the second and higher-line treatment for metastatic breast cancer. The adverse reactions of pyrotinib were tolerable in general.Keywords: pyrotinib, HER2, metastatic breast cancer, trastuzumab, inetetamab
