Trastuzumab Deruxtecan (T-DXd) With Pyrotinib in First-line HER2-positive Unresectable or Metastatic Breast Cancer Trial

This is an exploratory, single-arm, multi-center study to assess the efficacy and safety of T-DXd combined with pyrotinib as the first-line treatment of HER2-positive metastatic breast cancer. This study is planned to recruit 3 to 12 patients in safety run-in (Part A) and 39 to 42 patients in dose expansion (Part B) in several investigational sites in China. The total number of patients enrolled in the study will be 45 to 51. Among them, 45 patients will start at the recommended dose. Patients who fulfill all the inclusion criteria and none of the exclusion criteria will receive T-DXd combined with pyrotinib until confirmed progressive disease. Patients will attend a safety follow up visit 40 days after last dose of T-DXd with pyrotinib. There are two main parts to this study; Part A, Combination dose finding and Parts B, Dose expansion. Tumor assessments will be performed at Screening as baseline with follow-up every 9 weeks(±7 days) from the date of first dosing date of T-DXd with pyrotinib for 54 weeks, and then every 12 weeks (±7 days) until confirmed objective disease progression. Primary Objective for Part A: To define the recommended dose of pyrotinib combined with T-DXd Recommended dose Secondary Objective for Part A: To investigate the safety and tolerability of T-DXd + pyrotinib as first-line treatment of HER2-positive metastatic breast cancer. Primary Objective for Part B : To determine the efficacy of T-DXd + pyrotinib as first-line treatment of HER2-positive metastatic breast cancer. Secondary Objective for Part B : To further determine the efficacy of T-DXd + pyrotinib as first-line treatment of HER2-positive metastatic breast cancer and To further evaluate the safety and tolerability profile of T-DXd + pyrotinib as first-line treatment of HER2-positive metastatic breast cancer.

NCT Number	NCT06245824
Lead Sponsor	Cancer Institute and Hospital, Chinese Academy of Medical Sciences
Conditions	Breast Cancer
Enrollment	51 participants
Start Date	2024-01-30
Primary Completion	2026-03-01 (estimated)
Study Completion	2026-12-01 (estimated)
Updated on ClinicalTrials.gov	2024-02-07