Embrace Bio Announces $210M Global Licensing Deal for KLK2/CD3 TCE Bispecific Antibody Targeting Metastatic Prostate Cancer

On May 27, EpimAb Biotherapeutics announced that it had entered into a global licensing agreement with Juri Biosciences, a portfolio company of TCG Labs Soleil. The agreement grants Juri Biosciences exclusive worldwide rights to develop a T-cell engager (TCE) targeting kallikrein-related peptidase 2 (KLK2) and CD3 for the treatment of metastatic prostate cancer.

Under the terms of the agreement, EpimAb Biotherapeutics is entitled to receive up to $210 million (approximately RMB 1.511 billion), including an upfront payment, development-, registration-, and commercialization-related milestone payments, as well as royalties.

Kallikrein-Related Peptidase 2 (KLK2) is one of the most promising targets in the field of prostate cancer therapy. The serine protease encoded by the KLK2 gene exhibits highly specific expression in prostate cancer, with negligible expression in non-prostatic tissues, and is closely associated with tumor aggressiveness and castration resistance.

Studies have shown that KLK2 drives cancer progression by activating the androgen receptor (AR) signaling pathway, promoting angiogenesis, and remodeling the tumor microenvironment. In particular, its membrane-bound form (mKLK2), due to its unique biological properties, has emerged as an ideal target for radioligand therapy and bispecific antibodies.

With its highly specific expression in tumors and negligible expression in non-prostatic tissues, KLK2 has emerged as an ideal target for the development of T-cell engagers (TCEs), radioligand therapy (RLT), and CAR-T cell therapies. As a rising star in prostate cancer treatment, KLK2 is driving clinical progress through multidimensional breakthroughs, including radiotherapy, bispecific antibodies, and small-molecule drugs.

Currently, few companies worldwide are developing therapies targeting KLK2. Among them, Johnson & Johnson has identified KLK2 as a key target in its prostate cancer portfolio and is concurrently pursuing the development of bispecific T-cell engagers (TCEs), radioligand therapy (RLT), and CAR-T cell therapies.

In the 2025 American Society of Clinical Oncology (ASCO) abstracts, Johnson & Johnson presented clinical study data for its drug JNJ-78278343 (pasritamig, an anti-CD3/KLK2 bispecific antibody) for the first time. According to the released data, the drug demonstrated a favorable safety profile. At the recommended phase 2 dose (RP2D; up to 300 mg administered intravenously every 3 or 6 weeks), the incidence of grade ≥3 treatment-related adverse events (TRAEs) was only 4.4%, and the incidence of cytokine release syndrome (CRS) was 8.9%, with all CRS cases being grade 1. However, clinical efficacy requires improvement. The PSA50 response rate was 42.4%. In patients with lymph node involvement with or without bone metastases, the objective response rate (ORR) was 16.1% (n=5/31), whereas in patients with visceral disease, the ORR was 3.7% (n=2/54).

This data release not only marks the drug project’s public debut but also represents the first clinical data presentation for a KLK2-targeted TCE (KLK2-TCE), thereby bolstering confidence in the development of KLK2-directed RLT and TCE therapeutics.

In China, EpimAb Biotherapeutics’ KLK2-TCE program is in the preclinical research stage. This collaboration between EpimAb Biotherapeutics and Juri Biosciences will accelerate the global development of the KLK2 TCE program, bringing new therapeutic hope to patients with metastatic prostate cancer worldwide.

Dr. Wu Chenbing, Founder and CEO of EpimAb Biotherapeutics, stated that although this collaboration with Juri falls within the oncology field, it may reflect the fact that the CD3/KLK2 TCE track is still in its early stages. By granting overseas rights to Juri, a partner supported by the experienced team at TCG Labs Soleil, Epimab aims to share development burdens and continue validating the broad potential of its TCE platform beyond immunology and hematology.

TCG Labs Soleil is a venture capital firm that integrates dedicated capital with its own biotechnology R&D center. This collaboration marks the successful application of TCG Labs Soleil’s “venture capital–biotechnology” model, which rapidly advances innovative therapies to the clinical stage by integrating specialized capital, scientific leadership, and operational infrastructure.

According to a press release from EpimAb Biotherapeutics, Juri Biosciences is one of the portfolio companies formed by TCG Labs Soleil and operates as a NewCo. Following this licensing agreement, Juri plans to rapidly advance its KLK2/CD3 TCE into clinical trials. Dr. Charles Sawyers, Founding Head of the Human Oncology and Pathogenesis Program at Memorial Sloan Kettering Cancer Center, will serve as Strategic Scientific Advisor. He will work closely with the TCG Labs Soleil team to support the project and help guide the development of KLK2-targeted therapies.

This collaboration is not EpimAb Biotherapeutics’ first NewCo deal. In September 2024, Vignette Bio, incubated by Foresite Labs and invested in by Foresite Capital, entered into a license agreement with EpimAb for EMB-06, a BCMA-targeting T-cell engager (TCE). According to the announcement, Vignette obtained exclusive rights to develop and commercialize EMB-06 outside Greater China. In consideration, EpimAb will receive an upfront payment of $60 million, up to $575 million in development, regulatory approval, and commercialization milestone payments, tiered royalties based on net sales, and an equity stake in Vignette.

EpimAb Biotherapeutics’ NewCo success began with its proprietary bispecific antibody technology platforms—FIT-Ig and MAT-Fab. FIT-Ig employs a “2+2” tetravalent bispecific antibody design that requires no amino acid mutations or linker peptides, thereby avoiding steric hindrance and structural heterogeneity. This structural design enables EpimAb to combine any two monoclonal antibodies into a single bispecific molecule without altering the original monoclonal antibody sequences, significantly reducing R&D complexity and costs.

EpimAb’s CD3-binding domain library also provides unique advantages for the development of T-cell engager (TCE) molecules. This library offers diverse CD3-binding arms with optimized affinity to balance efficacy and safety, demonstrating particular excellence in reducing the risk of cytokine release syndrome (CRS). The low incidence of CRS (limited to Grade 1) and high safety profile exhibited by EMB-06 in clinical trials are a direct reflection of this technological advantage.

The MAT-Fab platform enables EpimAb Biotherapeutics to rapidly generate and screen a series of T-cell engager molecules during the early discovery phase, advancing candidate molecules with optimal efficacy and safety profiles into pre-IND and clinical stages, thereby complementing the FIT-Ig platform. The synergistic effect of these platforms has allowed EpimAb Biotherapeutics to establish technical barriers in the bispecific antibody field, enhancing the international competitiveness of its products, which serves as the core foundation for its successful global expansion through the NewCo model.

Driven by factors such as convenience, accessibility, and production costs, T-cell engager (TCE) bispecific antibody therapies are poised to become the next major investment hotspot in innovative drugs. In 2024, there were nearly 20 global transactions involving investigational TCE bispecific antibodies, with a total deal value exceeding $8.5 billion. In addition to EpimAb Biotherapeutics, other NewCo deals finalized last year—such as those for Genor Biopharma’s monoclonal antibody and Weilizhibo’s trispecific antibody—also involved pipeline assets in the TCE field.

EpimAb Biotherapeutics’ $210 million NewCo overseas partnership marks a significant milestone in the field of domestically developed TCE bispecific antibodies and represents another successful application of the NewCo model in this sector.

As the wave of Chinese innovative pharmaceutical companies expanding overseas gains momentum, the NewCo model is emerging as a key pathway for the internationalization of China’s innovative drugs. In 2024, business development (BD) deals in China’s innovative drug sector exhibited trends characterized by “low upfront payments, high transaction volume, substantial deal values, and diverse partnership counterparts,” with the NewCo model serving as a significant driver of this trend. Compared with traditional BD models, the NewCo model offers higher upfront payment proportions and facilitates corporate innovation, resource integration, risk diversification, and benefit sharing.

As China accelerates the internationalization of its pharmaceutical regulatory framework and enhances its capacity for innovative drug R&D, the NewCo model is poised to become one of the predominant strategies for Chinese biopharmaceutical companies expanding globally, thereby strengthening the position of China’s pharmaceutical industry in global competition.