GSK to acquire CMG1A46 from Chimagen Biosciences to boost immunology pipeline

LONDON, UK, October 29, 2024 – GSK plc (LSE/NYSE: GSK) and Chimagen Biosciences (Chimagen), a private biotechnology firm, have announced a significant agreement whereby GSK will acquire CMG1A46, a dual CD19 and CD20-targeted T cell-engager (TCE) currently in clinical stages, from Chimagen for an upfront payment of $300 million. GSK intends to advance and market CMG1A46, particularly targeting B cell-driven autoimmune diseases like systemic lupus erythematosus (SLE) and lupus nephritis (LN), and may later extend its application to other related autoimmune conditions.

GSK has been recognized for over a decade as a leader in lupus treatment. This latest agreement highlights the need for innovative therapeutic approaches to address the diverse manifestations of lupus and the ongoing challenges, especially for patients with severe conditions resistant to current treatments.

Tony Wood, Chief Scientific Officer at GSK, emphasized the potential of CMG1A46: "Our extensive research in systemic lupus erythematosus and lupus nephritis has enhanced our understanding of the underlying mechanisms driving B cell-related diseases. CMG1A46 presents an exciting novel treatment aimed at profound B cell depletion, which could meet the unmet needs in lupus and other autoimmune conditions."

CD20 is a well-established target in autoimmune disease therapy, and emerging clinical data indicate that CD19 could offer a unique treatment approach due to its expression on a wider range of B cell types. Preclinical studies of CMG1A46, designed to target both CD19 and CD20, have demonstrated rapid and significant B cell depletion in blood and tissues, potentially leading to more sustained patient responses.

Chimagen’s CEO, Zhenhao Zhou, expressed enthusiasm about the agreement: "The potential of CMG1A46 to enhance the lives of those with autoimmune diseases is significant, and GSK’s involvement will expedite this vision. This deal further validates our proprietary T cell-engager platform, and we are committed to continuing our development of innovative multi-specific antibody therapeutics."

Currently, CMG1A46 is undergoing phase I clinical trials for leukemia and lymphoma in the US and China. GSK's goal is to initiate a phase I trial for lupus in 2025.

Under this agreement, GSK will provide a $300 million upfront payment for full global rights to CMG1A46. Additionally, Chimagen is set to receive up to $550 million in success-based development and commercial milestone payments. The agreement is subject to standard conditions, including necessary regulatory approvals under the Hart-Scott-Rodino Act in the US.

CMG1A46 is characterized as a dual CD19 and CD20-targeting T cell-engager (TCE), resembling an IgG molecule with high affinity for CD19 and CD20 positive B cells and lower affinity for CD3, which could potentially reduce the toxicities often associated with TCEs.

Chimagen Biosciences is a clinical-stage biotechnology company dedicated to discovering and developing novel multi-specific T cell-engagers and NK cell-engagers, leveraging its proprietary antibody engineering platforms. The company aims to create breakthrough therapies to improve patient lives, particularly those suffering from cancer and autoimmune diseases.

GSK is a global biopharmaceutical company whose mission is to combine science, technology, and talent to stay ahead of disease.