HENLIUS (02696): The phase II / III clinical study of HLX22 combined with HLX87 for first-line treatment of HER2-positive recurrent or metastatic breast cancer (BC) patients has completed the first patient dosing in China.

HENLIUS (02696) announced that recently, the phase 2/3 clinical study of HLX22 (recombinant humanized anti-HER2 monoclonal antibody injection) in combination with HLX87 (targeted HER2 antibody-drug conjugate) for first-line treatment of HER2-positive recurrent or metastatic breast cancer patients has completed dosing for the first patient in China (excluding Greater China region). This study is an open-label, randomized, multicenter phase 2/3 clinical study evaluating the combination of HLX22 with HLX87 as first-line treatment for HER2-positive recurrent or metastatic breast cancer patients. The study consists of two stages, with the first stage being an open-label, multicenter, randomized, parallel-controlled phase 2 study. Eligible subjects will be randomly assigned in a 2:2:1:1 ratio to receive HLX22 combined with HLX87, pertuzumab combined with HLX87, pertuzumab combined with trastuzumab emtansine, or pertuzumab combined with trastuzumab and paclitaxel. The primary endpoints of the first stage are objective response rate (ORR) and progression-free survival (PFS) assessed by the independent imaging assessment committee (BICR). The second stage is an open-label, multicenter, randomized, parallel-controlled phase 3 study. Eligible subjects will be randomly assigned in a 1:1 ratio to receive HLX22 combined with HLX87 or pertuzumab combined with trastuzumab and paclitaxel. The primary endpoint of the second stage is PFS assessed by BICR. The main objective of this study is to evaluate the clinical efficacy of HLX22 in combination with HLX87 as first-line treatment for HER2-positive recurrent or metastatic breast cancer, with secondary objectives including the evaluation of safety, tolerability, pharmacokinetic (PK) characteristics, immunogenicity of HLX22 combined with HLX87, and exploring potential predictive or resistance biomarkers.