Boostimmune Secures Broad Japanese Patent for Antibody Technology Targeting Tumor Microenvironment Immunosuppression

SEOUL, South Korea — On July 13, 2026, Boostimmune announced the grant of a Japanese patent protecting its innovative antibody technology designed to inhibit translationally controlled tumor protein (TCTP) released from dead tumor cells. This inhibition aims to suppress the accumulation of myeloid-derived suppressor cells (MDSCs) within the tumor microenvironment, a key factor in tumor immune evasion.

Unlike patents limited to specific antibody complementarity-determining regions (CDRs) or amino acid sequences, the granted claims are functionally defined. They cover anti-TCTP antibodies that block TCTP activity extracellularly and suppress MDSC accumulation, including polymorphonuclear MDSCs (PMN-MDSCs). The claims also extend to cancer therapeutics and therapeutic compositions containing these inhibitors as active ingredients.

This patent significantly enhances Boostimmune’s intellectual property portfolio in Japan, underpinning the development and potential commercialization of its proprietary BIO101 antibody candidate. BIO101 is an immuno-oncology program focused on modulating MDSCs, which are major immunosuppressive cells in the tumor microenvironment.

TCTP has traditionally been recognized for its intracellular roles. However, research has shown that TCTP can be released into the extracellular space during tumor cell death, where it influences immunosuppressive myeloid cells. This extracellular TCTP promotes MDSC recruitment and accumulation in tumors, contributing to the suppression of antitumor immune responses.

Boostimmune’s therapeutic strategy involves using antibodies to block extracellular TCTP, thereby reducing MDSC accumulation and restoring antitumor immunity. The newly granted patent is expected to be a critical asset for the clinical development, licensing, and commercialization of TCTP-targeting antibody therapeutics in Japan, especially those employing similar mechanisms of action.

BIO101 originated from foundational research led by Professor Tadatsugu Taniguchi, Professor Emeritus at the University of Tokyo and a globally recognized immunologist. His team’s 2021 publication in Nature Immunology demonstrated extracellular TCTP’s role in promoting MDSC accumulation within tumors. Professor Taniguchi is also a co-founder of Boostimmune.

Building on this research, Boostimmune has identified and optimized antibodies that block TCTP function. Preclinical development has focused on antibody binding properties, inhibition of MDSC accumulation, and activation of antitumor immune responses.

Boostimmune CEO Dr. Gwanghee Lee emphasized the significance of the patent’s functional claim scope, stating, "This Japanese patent is significant because it is not limited to the sequence of a single BIO101 antibody. Rather, the granted claims are centered on the function of inhibiting TCTP released from dead tumor cells to suppress MDSC accumulation in tumors, as well as the related therapeutic uses and compositions."

Dr. Lee added, "Because this patent may be relevant to the development and commercialization of therapeutics that use TCTP antibodies to regulate the immunosuppressive tumor microenvironment through the same or a similar mechanism, we intend to accelerate the development of BIO101 while actively pursuing strategic collaborations with global pharmaceutical and biotechnology companies."

Founded in 2021 by Dr. Lee and Professor Taniguchi, Boostimmune is an oncology-focused biotechnology company advancing multiple biologics-based oncology programs. These include BIO101 and novel antibody-drug conjugate programs targeting TCTP and related mechanisms.

The Japanese patent grant represents a pivotal milestone for Boostimmune, reinforcing its position in the competitive immuno-oncology landscape and supporting its strategic goals for global commercialization of TCTP-targeting antibody therapeutics.