On November 13, Guanglonghui announced that Yiming Anke-B (01541.HK) has launched a Phase II clinical trial for the treatment of hormone receptor-positive (ER+) metastatic breast cancer following failure or recurrence of endocrine therapy, and has recruited the first patient.

In addition, the Phase I dose escalation study of IMM27M is expected to be completed by the end of 2023, with results as follows (as of August 6, 2024): a total of eight evaluable ER+ advanced or metastatic breast cancer patients were recruited in the Phase I trial. Among them, two cases achieved partial response (PR) and four patients had stable disease (SD), resulting in an overall response rate (ORR) of 25.0% and a disease control rate (DCR) of 75.0%; this shows positive efficacy signals; and IMM27M is safe and well tolerated, with the highest dose of 7.5 mg/kg explored in Phase I showing no observed dose-limiting toxicity.

IMM27M is a new generation of cytotoxic T lymphocyte-associated protein 4 (CTLA-4) antibody with enhanced antibody-dependent cellular cytotoxicity (ADCC) activity. It can induce a strong immune response targeting the regulatory T cells that excessively express CTLA-4 and have immunosuppressive effects, promoting the elimination of regulatory T cells from the tumor microenvironment (TME), thereby enhancing T cell anti-tumor responses.