Catumaxomab

Mechanism of action of Catumaxomab

Catumaxomab is a monoclonal antibody that was developed for the treatment of malignant ascites in patients with epithelial cell cancer. It is a bi-specific monoclonal antibody, meaning it is designed to bind to two different types of antigens. Catumaxomab targets the epithelial cell adhesion molecule (EpCAM) on tumor cells and the CD3 antigen on T cells, facilitating a tri-cellular complex that includes tumor cells, T cells, and accessory cells such as macrophages and natural killer cells.

Mechanism of Action

Catumaxomab's mechanism of action involves the formation of a tri-cellular complex that enhances the immune system's ability to attack tumor cells. By binding to EpCAM on tumor cells and CD3 on T cells, catumaxomab brings these cells into close proximity, allowing T cells to exert cytotoxic effects on the tumor cells. Additionally, the Fc region of catumaxomab can bind to Fc receptors on accessory cells, further promoting the immune response against the tumor.

Clinical Use

Catumaxomab was primarily used for the treatment of malignant ascites, a condition characterized by the accumulation of fluid in the peritoneal cavity due to cancer. This condition is often seen in patients with advanced ovarian cancer, gastric cancer, and other epithelial cancers. The administration of catumaxomab involves intraperitoneal infusion, allowing direct interaction with tumor cells in the peritoneal cavity.

Development and Approval

Catumaxomab was developed by the German biotechnology company Trion Pharma in collaboration with Fresenius Biotech. It was approved for use in the European Union in 2009. However, due to various factors, including market conditions and strategic decisions by the developing companies, catumaxomab was withdrawn from the market in 2017.

Structure

Structure of Catumaxomab

Catumaxomab is a rat-mouse hybrid monoclonal antibody. It is composed of two different immunoglobulin chains, one derived from a rat and the other from a mouse. This hybrid structure allows it to bind to both human and murine antigens, facilitating its bi-specific action.

Side Effects

The administration of catumaxomab can lead to several side effects, primarily due to its immune-stimulating properties. Common side effects include fever, nausea, vomiting, and abdominal pain. These effects are generally manageable with supportive care and premedication.

Related Pages

• Monoclonal antibody
• Bi-specific monoclonal antibody
• Epithelial cell adhesion molecule
• CD3 (immunology)
• Malignant ascites