EpimAb Biotherapeutics Secures $60 Million Upfront in EMB-06 Out-Licensing Deal with Vignette Bio

On September 4, EpimAb Biotherapeutics and Vignette Bio, Inc. announced that they had entered into a licensing agreement for EMB-06, EpimAb’s T-cell engager (TCE) molecule targeting BCMA.

Under the terms of the agreement, EpimAb Biotherapeutics will grant Vignette Bio exclusive rights to develop and commercialize EMB-06 outside of Greater China (including mainland China, Hong Kong, Macau, and Taiwan), while EpimAb Biotherapeutics will retain the rights to EMB-06 within Greater China. EpimAb Biotherapeutics will receive a total upfront consideration of $60 million in cash and equity in Vignette Bio, and will be entitled to receive up to $575 million in development, regulatory, and commercialization milestone payments, as well as tiered royalties based on net sales.

Vignette Bio, established in 2024, is dedicated to innovative therapies for immune and inflammatory diseases. Incubated by Foresite Labs—a platform led by a team of experienced scientists, engineers, and operators—the company operates on the belief that applying data science tools with scientific rigor will significantly accelerate scientific discovery and the development of new products and services that benefit patients. Vignette Bio has received joint investment from Foresite Capital, Qiming Venture Partners USA, Samsara Biocapital, and Mirae Asset Capital Life Science.

EpimAb Biotherapeutics, founded in 2016, is a clinical-stage biopharmaceutical company specializing in the development of multispecific antibodies. Leveraging extensive in-house research and technical capabilities, including its proprietary bispecific antibody technology platforms FIT-Ig® (Fabs-In-Tandem Immunoglobulin) and MAT-Fab (Monovalent Asymmetric Tandem Fab), EpimAb Biotherapeutics is advancing a portfolio of unique pipeline projects globally, including innovative preclinical and clinical-stage programs aimed at benefiting cancer patients.

EpimAb Biotherapeutics focuses on leveraging its proprietary FIT-Ig bispecific antibody technology platform.^®Conduct research and development of innovative biological drugs. According to reports, FIT-Ig^®This technology platform employs molecular biology techniques to fuse two monoclonal antibody sequences into a bispecific antibody with a unique structure. It is the only bispecific antibody technology globally that requires neither amino acid mutations nor the inclusion of linker peptides or any non-antibody sequences, thereby offering high druggability and industrialization efficiency.

EMB-06 involved in this transaction is based on FIT-Ig^®Developed on a proprietary technology platform, EMB-06 is a novel BCMA×CD3 T-cell engager bispecific antibody. This bispecific antibody mediates the specific killing of BCMA-expressing tumor cells by binding to BCMA on the surface of tumor cells and activating T cells, and is primarily indicated for the treatment of relapsed or refractory multiple myeloma (RRMM).

In terms of clinical trials, EMB-06 has demonstrated excellent clinical performance, indicating strong therapeutic potential. Its Phase I/II study is currently evaluating its safety, tolerability, pharmacokinetics, and preliminary antitumor activity in patients with relapsed or refractory multiple myeloma.

As of August 28, 2023, 33 patients had received EMB-06 at varying doses. Treatment-related adverse events (TRAEs) were reported in 20 (61%) patients, including 7 (21%) patients who experienced grade 3 or higher TRAEs. Preliminary results indicate that EMB-06 demonstrates a differentiated safety profile in patients with relapsed/refractory multiple myeloma (RRMM), with low incidences of cytokine release syndrome (CRS) and neurotoxicity.

Leveraging its FIT-Ig® technology platform, EpimAb Biotherapeutics has pioneered innovations in major anti-tumor mechanisms, including tumor-targeted therapies, dual immune checkpoints, and immune cell redirection. The company currently boasts five clinical-stage candidate pipelines and more than ten preclinical drug candidates.

In addition to EMB-06, EpimAb Biotherapeutics has other pipeline candidates in clinical development:

• EMB-01 simultaneously targets EGFR and cMET on the surface of tumor cells and is currently undergoing Phase I/II clinical trials in both the United States and China for non-small cell lung cancer and multiple gastrointestinal tumors;

• EMB-02 is a symmetric IgG-like bispecific antibody targeting PD-1 and LAG-3 for the treatment of advanced solid tumors. The antibody is designed to target human PD-1 and LAG-3 simultaneously or independently, disrupting immune suppression mediated by both pathways, thereby restoring T-cell effector function to enhance anti-tumor immunity. Currently, a global Phase I/II clinical trial is underway in the United States, Australia, and China;

• EMB-07: EMB-07 is a T-cell-engaging bispecific antibody targeting a novel tumor-associated antigen (ROR1) and CD3. The molecular design of EMB-07 is based on EpimAb Biotherapeutics’ proprietary bispecific antibody platform. By bridging tumor cells and T cells and activating T cells, EMB-07 mediates T cell-specific killing of solid tumors. In preclinical studies, EMB-07 demonstrated favorable efficacy and safety profiles;

• EMB-09: EMB-09 is based on FIT-Ig^®EMB-09 is a bispecific antibody developed through proprietary technology that blocks the interaction between PD-1 and PD-L1 and conditionally activates the OX40 signaling pathway via PD-L1-mediated crosslinking. The selection of its OX40-binding site and optimization of the Fc region confer distinct differentiated advantages to EMB-09 among comparable products. Meanwhile, EMB-09 enhances T-cell activation while significantly reducing non-specific immune cell activation in non-tumor environments. In preclinical in vitro and in vivo models, this molecule demonstrated superior immune cell activation and antitumor activity compared to anti-PD-L1 or anti-OX40 monoclonal antibodies alone or in combination, highlighting the unique synergistic effects of the bispecific antibody format.

As of now, FIT-Ig^®The platform has secured multiple global patents. EpimAb Biotherapeutics has also leveraged this platform to successfully advance several product candidates into clinical stages, facilitating significant overseas business development deals.

Dr. Chenbing Wu, CEO and Founder of EpimAb Biotherapeutics, stated, “EpimAb Biotherapeutics is pleased to reach this collaboration agreement with Vignette Bio regarding EMB-06. Vignette Bio is well-positioned to realize the potential of EMB-06. As the first molecule developed using our proprietary T-cell engager platform, EMB-06 has already demonstrated promising clinical efficacy in evaluations among patients with multiple myeloma. We look forward to further assessing the potential of EMB-06 in autoimmune diseases.”

In recent years, Chinese pharmaceutical companies have made rapid progress in the field of bispecific antibody drugs. Multiple domestically produced bispecific antibodies have not only achieved significant advancements in China but also realized important business development opportunities in international markets.

In December 2022, Akeso and Summit Therapeutics entered into a collaboration and license agreement for ivonescimab, a PD-1/VEGF bispecific antibody, with an upfront payment of $500 million and a total potential transaction value of up to $5 billion.As a leading enterprise in this field, Akeso has successfully launched its two bispecific antibody drugs, cadonilimab and ivonescimab. Furthermore, ivonescimab has demonstrated superior efficacy in pivotal Phase III clinical trials, further enhancing its competitiveness in the global market.

YiMing Biopharma and Tongrun Bio have also achieved significant business development (BD) progress in the bispecific antibody field.

In early August 2024, ImmuneOnco licensed the rights to its PD-L1/VEGF bispecific antibody IMM2510 and next-generation CTLA-4 antibody IMM27M outside Greater China to Instil Bio, in a deal valued at over $2 billion. In late August, ImmuneOnco received a $10 million upfront payment.

On August 9, 2024, Merck & Co. reached an agreement with Tongrun Biopharma to acquire the global rights to the CD3/CD19 bispecific antibody CN201, paying a $700 million upfront fee.

Furthermore, BioNTech licensed Promab Biotechnologies’ PD-L1/VEGF bispecific antibody PM8002 for over $1 billion, further validating the market potential of this class of therapeutics.

In addition to companies that have already secured business development (BD) deals, 3SBio, RemeGen, Junshi Biosciences, and SinoCellTech are also actively advancing the research, development, and clinical trials of their bispecific antibody drugs. These agents target multiple high-profile pathways, including PD-1/VEGF, and have demonstrated favorable efficacy and safety profiles in clinical studies. As these therapies gradually enter the market, Chinese bispecific antibodies are expected to assume a more prominent role in the global pharmaceutical industry over the coming years, offering patients additional effective treatment options.