[Shanghai, China] Shanghai Baoji Pharmaceutical Co., Ltd. (hereinafter referred to as "Baoji Pharmaceutical") recently announced that its Investigational New Drug (IND) application for KJ015, a subcutaneous formulation of a HER2-targeting bispecific antibody, was officially approved by the U.S. Food and Drug Administration (FDA) on August 21, 2026, authorizing it to conduct clinical trials in the United States. This is another significant milestone for KJ015, following its IND approval from the China National Medical Products Administration (NMPA) in December 2024 and the initiation of Phase I clinical trials in China in June 2025 .

Powered by universal light chain technology: An antibody achieves dual blockade with Herceptin and Perjeta.

KJ015 is an innovative subcutaneous formulation of a bispecific anti-HER2 antibody derived from universal light chain technology. It is designed with two Fab arms containing universal light chains, forming a near-native IgG1 structure. By maintaining high affinity for both epitopes simultaneously, KJ015 can simultaneously target the clinically validated epitopes recognized by Herceptin® (trastuzumab) and Perjeta® (pertuzumab), inhibiting HER2 homodimerization as well as heterodimerization of HER2 with EGFR, HER3, and HER4.
Compared to existing anti-HER2 bispecific antibodies, KJ015 has a more rational affinity and structural design, enabling it to more effectively inhibit the dimerization of HER2 and ERBB family members, thus weakening downstream signals such as MAPK and PI3K/Akt. Simultaneously, this dual binding leads to antibody-antigen aggregation, promoting the internalization and recognition of tumor antigens, distinguishing its mechanism of action from the simple combination of monoclonal antibodies.
Preclinical studies have shown that KJ015 has significantly better tumor-suppressive effects on Calu-3, N87, and BT474 xenografts than the combination therapy of Herceptin® and Perjeta®. In the Calu-3 xenograft model, KJ015 showed good tolerability in tumor-bearing mice, demonstrating its potential as an effective and safe anti-tumor drug. Its synergistic effect also provides broad prospects for the development of subsequent combination therapies.
A Revolution in Subcutaneous Drug Delivery: Overcoming Clinical Pain Points in HER2 Treatment

In the HER2 antibody market, high cost, cardiotoxicity, and the inconvenience of intravenous administration have long limited drug accessibility and adherence. Traditional intravenous infusion requires patients to spend several hours in the hospital for treatment, while subcutaneous administration can shorten the administration time to several minutes, significantly improving patient convenience and reducing the risks associated with intravenous administration. KJ015's near-natural IgG1 structure, coupled with its deamidated design, makes it chemically stable and allows for high expression levels in large-scale production. Its stability at high concentrations also facilitates the formulation of subcutaneous preparations with recombinant human hyaluronidase, laying a solid foundation for convenient clinical application.
Dual reporting between China and the US, global layout: A key leap in pipeline internationalization

KJ015 was independently developed by Baoji Pharmaceutical, which owns the global rights to its development and commercialization. Currently, the Phase I clinical trial of KJ015 in China is progressing smoothly and is expected to be completed in the second half of 2026. Following this IND approval in the United States, KJ015 will officially enter the clinical development phase in both China and the United States, laying the foundation for subsequent registration and application in major global markets.

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