DoubexMAB3

DoubexMAB3 is a humanized monoclonal antibody under development by Doubex Biotherapeutics. It is designed to bind to antigen X, a transmembrane protein expressed at higher levels on certain tumor cells, with the aim of interrupting signaling that promotes tumor growth and survival. The antibody is also intended to engage immune effector mechanisms, such as antibody-dependent cellular cytotoxicity, to promote tumor cell destruction.

Development and research: Preclinical studies have demonstrated high-affinity binding to antigen X and selectivity for tumor-associated expression. In vitro assays reported blockade of the X signaling pathway, while in vivo xenograft models showed delayed tumor growth and enhanced infiltration of immune cells. Pharmacokinetic and toxicology data in animals supported a dosing interval in humans ranging from two to four weeks, informing initial clinical trial design.

Clinical status: DoubexMAB3 is investigational and has not been approved for any indication. An Investigational New Drug application was submitted to regulatory authorities, and a Phase I clinical trial was initiated to evaluate safety, tolerability, pharmacokinetics, and preliminary efficacy in adults with advanced X-expressing cancers. Public disclosure of efficacy results has not been established.

Manufacturing and formulation: The antibody is produced in recombinant Chinese hamster ovary (CHO) cells and purified to clinical-grade standards. The product is formulated for intravenous infusion and maintained under standard cold-chain storage. Regulatory status remains investigational, with production governed by good manufacturing practice (GMP) guidelines.

Safety considerations: Early-stage studies report potential adverse events such as infusion reactions, fatigue, and digestive symptoms, with laboratory abnormalities including transient cytopenias in some participants. As with other immunomodulatory antibodies, infection risk and immune-related effects require careful monitoring in clinical trials.