Fu Hong Han Lin (02696): A phase 1 clinical study of HLX3902 injection for the treatment of metastatic castration-resistant prostate cancer and other advanced solid tumors completed the first patient administration in China

Zhitong Finance App News, Fu Hong Han Lin (02696) announced that recently, the first phase clinical study of HLX3902 injection (steap1xCD3xCD28 trispecific antibody) (HLX3902) for the treatment of metastatic castration-resistant prostate cancer (mCRPC) and other advanced solid tumors was completed in China (excluding Hong Kong, Macao and Taiwan regions of China, same below). The company plans to conduct further relevant clinical trials in Australia when conditions are met.

This study is an open, first human phase 1a clinical study to evaluate the safety, tolerability, pharmacokinetic characteristics, and initial efficacy of HLX3902 in patients with metastatic castration-resistant prostate cancer (mCRPC) and other advanced solid tumors. The study set a total of 8 dose levels of 0.005 mg to 1.5 mg, with a treatment cycle every 4 weeks. The 0.005 mg dose group used an accelerated titration design, and the remaining 7 dose groups used a “3+3” dose escalation design. The main purpose of this study was to evaluate the safety and tolerability of HLX3902 in patients with metastatic castration-resistant prostate cancer (mCRPC) and other advanced solid tumors, and to determine its maximum tolerable dose (MTD). The primary endpoints were the incidence of dose-limiting toxicity (DLT) events and the maximum tolerated dose (MTD) of HLX3902.

HLX3902 is a three-specific antibody drug independently developed by the company. It is intended to treat metastatic castration-resistant prostate cancer (mCRPC) and other advanced solid tumors. HLX3902 is a tri-specific T-cell connector that can simultaneously target STEAP1, CD3, and CD28. HLX3902 can enhance the ability of T cells to lyse STEAP1-expressing tumor cells by simultaneously activating CD3 and CD28, and enhance the activation, proliferation, and viability of T cells by optimizing T-cell activation first signal (CD3) and second signal (CD28), thereby achieving the goal of treating metastatic castration-resistant prostate cancer (mCRPC) and other advanced solid tumors. Preclinical studies have shown that HLX3902 has good anti-tumor efficacy and safety, and is expected to benefit clinically. In May and June 2026, HLX3902 was approved to conduct phase 1 clinical trials for the treatment of metastatic castration-resistant prostate cancer (mCRPC) and other advanced solid tumors in Australia and China, respectively.