中国已经批准使用不可逆式全ErbB抑制剂Pyrotinib治疗HER2阳性晚期乳腺癌。我们进行了一项全国范围的前瞻性观察性研究，以研究该人群中基于Pyrotinib的治疗的真实世界数据。纳入了来自中国61个研究点的患者。Pyrotinib基于当地医生的自主选择处方。评估了人口统计学、治疗模式、预后和安全性。主要结果是真实世界的无进展生存期(rwPFS)。在1129名患者中，437名(38.7%)、476名(42.2%)和216名(19.1%)患者分别作为一线、二线和三线或更后一线治疗中被应用Pyrotinib治疗。总体人群中的中位rwPFS(mrwPFS)为14.3(95% CI, 13.3-15.2)个月，一线治疗中的mrwPFS最长，为17.8(95% CI, 15.2-24.9)个月，其次是二线治疗中的14.4(95% CI, 12.9-15.3)个月。接受三线或更后一线治疗的患者的mrwPFS为9.3(95% CI, 8.4-11.8)个月。接受曲妥珠单抗或曲妥珠单抗-帕妥珠单抗治疗的患者的mrwPFS分别为14.3和13.6个月。Pyrotinib与曲妥珠单抗联合双重HER2阻断在总体人群中的mrwPFS为16.2个月，一线设置的数据尚不成熟。对于基线有脑转移的患者，mrwPFS为11.7个月。最常见的不良事件是腹泻（任何级别，73.5%；≥3级别，15.3%）。在真实世界中，基于Pyrotinib的治疗在一线、以及二线和更后一线治疗中显示出有希望的疗效，耐受性良好。进一步研究关于Pyrotinib的一线使用或新的联合方案可能有助于最大限度地发挥其抗肿瘤潜力。© 2023 UICC.

Pyrotinib, an irreversible pan-ErbB inhibitor, has been approved for treating HER2-positive advanced breast cancer in China. We conducted a nationwide, prospective observational study to examine the real-world data of pyrotinib-based therapy in this population. Patients from 61 sites across China were included. Pyrotinib-based regimens were prescribed at local physician's discretion. Demographics, treatment patterns, prognosis and safety were evaluated. The primary outcome was real-world progression-free survival (rwPFS). Of 1129 patients, pyrotinib-based therapy was prescribed as first-, second- and third- or later-line treatment in 437 (38.7%), 476 (42.2%) and 216 (19.1%) patients, respectively. Median rwPFS (mrwPFS) was 14.3 (95% CI, 13.3-15.2) months in the total population, with the longest mrwPFS of 17.8 (95% CI, 15.2-24.9) months in the first-line setting, followed by 14.4 (95% CI, 12.9-15.3) months in the second-line setting. Patients with third- or later-line treatment also achieved a mrwPFS of 9.3 (95% CI, 8.4-11.8) months. Patients with trastuzumab- or trastuzumab-pertuzumab-treated disease achieved a mrwPFS of 14.3 and 13.6 months, respectively. Dual HER2 blockade with pyrotinib plus trastuzumab showed a mrwPFS of 16.2 months in the total population, with data not mature in the first-line setting. For patients with baseline brain metastases, the mrwPFS was 11.7 months. The most common adverse event was diarrhea (any grade, 73.5%; grade ≥ 3, 15.3%). In real world, pyrotinib-based therapy shows promising effectiveness in the first-, as well as second- and later-line treatment, with acceptable tolerability. Further investigations regarding front-line use or novel combinations of pyrotinib might facilitate to maximize its anti-tumor potential.© 2023 UICC.