Wilex’s approach to treating renal cell cancer: monoclonal antibody therapy

Antibodies are part of the body's principal defense mechanism against disease-causing foreign organisms, such as virally infected cells and bacteria. Antibodies are able to recognize a specific molecular structure called an antigen and bind to that antigen. The binding triggers one or a number of physiological processes, which protect against disease. Antibodies are highly specialized and are capable of detecting the most subtle of molecular differences. Individual antibodies produced from a single cell-type are called monoclonal antibodies and can be generated against a specific target on cancer cells. This specificity and the fact that antibodies can be manufactured in large quantities with consistent quality make them attractive candidates for therapeutic substances. The understanding of the properties of antibodies and the possibility to produce human antibodies artificially provided the theoretical basis for the emergence of antibody-based cancer immunotherapeutics.

This new approach led to a search for tumor-specific antigens to which monoclonal antibodies could be directed. A monoclonal antibody directed to an antigen expressed only by a malignant cell could form the basis of a therapy with few, if any, side effects.

The WX-G250 antibody binds to the MN/CA IX antigen in over 90% of all clear cell renal cell carcinoma, thereby triggering an immune reaction called Antibody-Dependent Cellular Cytotoxicity (ADCC). Through this mechanism, effector cells of the immune system, for example, natural killer (NK) cells, are activated to kill the tumor cells.

So far more than 100 patients have been treated with the chimeric monoclonal antibody WX-G250 and the study medication was well tolerated. Patients who were treated with weekly administrations of WX-G250 demonstrated no severe side-effects.