How Antibodies Interact with Neck and Head Cancers
Each year, approximately 634,000 people are affected by squamous cell carcinoma of the neck and head. The flat, skin-like squamous cells are those that cover the inside of the nose, throat and mouth. Nearly one half of those who have advanced disease are likely to relapse with either local or distant metastases. Scientists are searching for a treatment for those whose protocols have not stopped the growth of their cancer. One such treatment under consideration makes use of a human monoclonal antibody known as zalutumumab.
Currently, patients are treated with radical surgery or radiotherapy. If this treatment is unsuccessful, or if the patient’s disease is not amenable to this type of treatment, platinum-based chemotherapy is used. However, there is no treatment available for those whose cancer continues to progress after the use of a platinum-based drug. Scientists studying zalutumumab are hoping that it may be able to increase the survival time of these patients.
Zalutumumab is a human monoclonal antibody. A human monoclonal antibody is a copy of a human antibody that is mass produced and designed to target a particular protein on a cancer cell. Zalutumumab is made to target the epidermal growth factor receptor on the cancer cell, blocking the receptor so the cell does not get the signal to replicate. In addition, when the zalutumumab is attached to the cancer cells, it is more easily recognized by the immune system. The antibody is a trigger for the immune system to attack and kill the cancer cells.
The European phase 3 trials were designed to compare zalutumumab and best supportive care, which may include chemotherapy or steroids, with best supportive care alone. The dose of zalutumumab used depended on the appearance or absence of a rash in the patient. The patients were randomly assigned to one of the two groups.
The results of the study, reported in 2010, showed that the median survival rate for those in the zalutumumab group was 6.7 months, while the rate in the control group was 5.2 months. Those who were in the zalutumumab group were found to have a longer progression-free survival than those in the control group. This monoclonal antibody helped to control the cancer in one-half of those treated with it as compared to one-quarter of those treated with best supportive care alone.
The researchers found that in this study, though the use of zalutumumab did not increase the overall survival rate, the progression-free survival time did increase in those patients who had no success with platinum-based chemotherapy. In addition, they found that dose titration based on the occurrence of a rash was safe in the case of zalutumumab. Researchers concluded that a human monoclonal antibody, zaluntumumab, was able to delay the progression of tumor growth in those with squamous cell carcinoma of the head and neck who had previously failed platinum-based treatment.