A multicentre single arm phase 2 trial of neoadjuvant pyrotinib and letrozole plus dalpiciclib for triple-positive breast cancer

• DOI: 10.1038/s41467-022-34838-w
• Publication Date: 2022-11-17T21:02:36Z
• Authors: Nan Niu; Fang Qiu; Qianshi Xu; Guijin He; Xi Gu; Wenbin Guo; Dianlong Zhang; Zhigao Li; Yi Zhao; Yong Li; Ke Li; Hao Zhang; Peili Zhang; Yuanxi Huang; Gangling Zhang; Hongbin Han; Zhengang Cai; Pengfei Li; Hong Xu; Guanglei Chen; Jinqi Xue; Xiaofan Jiang; Alireza Hamidian ...; Jinshi Li; Yu Zhao; Eduardo de Faria ...; Shiwen Huo; Huajun Li; Guy Jerusalem; Domenico Tripodi; Tong Liu; Xinyu Zheng; Caigang Liu
• Keywords: Clinical endpoint; Neoadjuvant Therapy; Leukopenia; Regimen; Letrozole

Current therapies for HER2-positive breast cancer have limited efficacy in patients with triple-positive (TPBC). We conduct a multi-center single-arm phase 2 trial to test the and safety of an oral neoadjuvant therapy pyrotinib, letrozole dalpiciclib (a CDK4/6 inhibitor) treatment-naïve, stage II-III TPBC Karnofsky score ≥70 (NCT04486911). The primary endpoint is proportion pathological complete response (pCR) axilla. secondary endpoints include residual burden (RCB)-0 or RCB-I, objective rate (ORR), pCR (bpCR), changes molecular targets (Ki67) from baseline surgery. Following 5 cycles 4-week treatment, results meet 30.4% (24 79; 95% confidence interval (CI), 21.3-41.3). RCB-0/I 55.7% (95% CI, 44.7-66.1). ORR 87.4%, 78.1-93.2) bpCR 35.4% 25.8-46.5). mean Ki67 expression reduces 40.4% at 17.9% (P < 0.001) time most frequent grade 3 4 adverse events are neutropenia, leukopenia, diarrhoea. There no serious event- treatment-related death. This fully oral, chemotherapy-free, triplet combined has potential be alternative regimen TPBC.