SINO BIOPHARM (01177) announced that its wholly-owned subsidiary Lixin Pharmaceutical Technology (Shanghai) Co., Ltd. has successfully completed the first patient enrollment in the China Phase I clinical trial for its independently developed Class 1 innovative drug LM-2417, a "NaPi2b/4-1BB bispecific antibody." This milestone marks the formal entry of this innovative therapy into the clinical development stage.

NaPi2b, encoded by the SLC34A2 gene, belongs to the SLC34 family of type II sodium-dependent phosphate transporters and plays a crucial role in regulating phosphate homeostasis in the body. NaPi2b demonstrates high expression in various malignant tumors including high-grade serous ovarian cancer, fallopian tube cancer, primary peritoneal cancer, as well as thyroid cancer, breast cancer, and non-squamous non-small cell lung cancer, while showing limited distribution in normal tissues. This characteristic positions it as a promising anti-tumor therapeutic target.

Currently, multiple companies worldwide have established presence in this field, though no related drugs have yet received market approval. LM-2417 is a NaPi2b/4-1BB bispecific antibody developed by Lixin Pharmaceutical based on its proprietary conditionally activated 4-1BB platform technology. The drug can specifically bind to NaPi2b on tumor cell surfaces and 4-1BB on immune cell surfaces.

This mechanism enables precise immune cell activation within the tumor microenvironment, thereby enhancing anti-tumor efficacy. Unlike traditional 4-1BB agonists, LM-2417 selectively activates the 4-1BB signaling pathway through a NaPi2b-dependent mechanism, potentially significantly reducing toxicity risks associated with non-specific immune activation.

Preclinical data demonstrate that LM-2417 not only induces durable anti-tumor immune memory but also exhibits significant synergistic effects when combined with other immunotherapy drugs. These characteristics position LM-2417 with the potential to become a first-in-class immunotherapy.

The current clinical study is an open-label, dose-escalation and dose-expansion Phase I/II clinical trial evaluating the safety, tolerability, pharmacokinetic characteristics, and preliminary efficacy of LM-2417 injection as monotherapy or in combination with other anti-tumor drugs in patients with advanced malignant solid tumors.

The Group will continue to rapidly advance the clinical research of this project, anticipating the early delivery of new immunotherapy clinical treatment options for patients.