How Does Bexxar Work?

Bexxar (the commercial name for the compound tositumomab and iodine I131 tositumomab) is a monoclonal or man-made antibody, which is a protein that attaches to and rids the body of a foreign substance (called an antigen). In more than 95% of low-grade or follicular non-Hodgkin's lymphoma cases, a specific cancerous antigen called CD-20 is expressed on the surface of the patient's B-cells (a type of white blood cell). When Bexxar is injected into the blood, it goes directly to these cells and attaches to them. The immune system is activated, as when the body reacts to an infection, and Bexxar tries to "gobble up" the cancer. But Bexxar carries an additional payload in the form of iodine 131, which gives off radiation, one of the most effective treatments for lymphoma. So Bexxar acts like a guided missile, delivering radiation to cancer cells while avoiding most normal tissues.

Treatment with Bexxar is a dramatic contrast to chemotherapy. Patients on chemotherapy face a repeating cycle of treatment and side effects followed by recovery, with the entire process extending over several months. Bexxar patients receive one test injection at the beginning of a week, and a therapeutic dose later in the week to conclude their treatment. According to Kaminski, "We have a patient celebrating her 10th year of remission thanks to Bexxar. Previously, after seven courses of chemotherapy, she had never known more than six months of remission. With Bexxar, your life is not spent in treatment. You're back to living."

According to the National Cancer Institute, nearly 300,000 Americans have NHL, making it the fifth most common cancer in the nation. NHL also has the second fastest-growing incidence of all cancers. Among those diagnosed with NHL, 140,000 are estimated to have the low-grade form of the disease which could potentially be helped by Bexxar in its current form and future advances on the horizon for the treatment.

return to top