Ovarian cancer remains one of the most lethal gynecological malignancies, characterized by late diagnosis, high relapse rates, and limited effectiveness of existing therapies. Current treatment strategies, including chemotherapy and emerging immunotherapies, are often associated with significant toxicity, resistance, or insufficient efficacy in solid tumors. Antibody-drug conjugates (ADCs) have emerged as a promising therapeutic modality; however, their success in ovarian cancer has been limited, largely due to the lack of suitable tumor-specific targets and challenges associated with antigen shedding.
MUC16 (CA125) is a well-established biomarker that is highly expressed in the majority of ovarian cancers. However, previous therapeutic approaches targeting MUC16 have failed in clinical settings, primarily because they recognize epitopes that are shed into the bloodstream, leading to antibody neutralization and reduced tumor targeting efficiency.
The objective of this Proof of Concept project was to overcome this key limitation by developing and validating a novel antibody-drug conjugate (2B5-ADC) targeting a non-shed, membrane-associated epitope of MUC16, thereby enabling more precise and effective delivery of cytotoxic agents to tumor cells.
The project pursued two main objectives:
1. Technical objective: To validate the feasibility and efficacy of the 2B5-ADC approach through antibody characterization, payload optimization, and preclinical model development.
2. Innovation and commercialization objective: To assess the commercial potential of the technology, develop an intellectual property and go-to-market strategy, and engage relevant stakeholders.
The expected impact of the project was to establish a new generation of ADC-based therapies for ovarian cancer with improved specificity, reduced off-target toxicity, and enhanced therapeutic efficacy. By directly addressing a major limitation of existing MUC16-targeting approaches, the project aimed to unlock the clinical potential of this well-established tumor antigen.
Importantly, during the course of the project, the scope of impact was further expanded. The 2B5 antibody was found to recognize MUC16 expressed in additional solid tumors. Combined with a clinically applicable patient stratification strategy based on circulating CA125 levels, this significantly broadens the potential clinical and commercial applications of the technology.
Overall, the project contributes to addressing a critical unmet medical need in oncology by providing a novel, mechanistically grounded therapeutic strategy with strong potential for translation into clinical applications and future commercialization.
