New Radioimmunotherapy Drug Proves Highly Effective For Killing Off B Cell Non-Hodgkin's Lymphoma

The study, published in the May 15, 2002, issue of Journal of Clinical Oncology, investigated the ability of the drug Zevalin to hone in on and kill off the non-Hodgkin’s lymphoma B cells. Zevalin is the first radioimmunotherapy drug developed specifically to fight this common but usually fatal cancer of the lymph glands that, for unknown reasons, is on the increase in the United States. About 56,000 people are diagnosed with this cancer annually.

The randomized study involved 143 patients with B cell non-Hodgkin’s lymphoma who had previously failed the standard chemotherapy treatments. The study found that 80 percent of patients who received Zevalin experienced a positive response in that their tumor shrunk. That compared to a 56 percent response rate in patients receiving only Rituxan, another drug used to treat the cancer.

Most noteworthy, 30 percent of the patients receiving Zevalin achieved complete remission with no evidence of the cancer present, compared to only 16 percent of patients taking Rituxan.

Radioimmunotherapy combines monoclonal antibodies, which are antibodies produced in a laboratory to react against a cancer cell, with the ability of radiation to kill off cancer cells. The mixture of radiation and antibodies is given intravenously and travels through the bloodstream to the cancer cells.

“Unlike chemotherapy which goes through the whole body, Zevalin carries the radiation payload directly to the tumor,” says Thomas Witzig, M.D., a Mayo Clinic hematologist. “The drug radiates only about a five millimeter area around the tumor.”

Along with its ability to hone in on cancer cells, the drug is easier on patients physically.

“One treatment is required on an outpatient basis, compared to a series of treatments with chemotherapy that can last four to six months and sometimes include hospitalization because of serious side effects,” says Dr. Witzig. “There’s no hair loss or prolonged fatigue, nausea or vomiting. The most significant side effect is a temporary decrease in the blood count.”

Dr. Witzig and Gregory Wiseman, M.D., a Mayo Clinic nuclear medicine specialist, led the phase III research study. This study was one of several clinical trials on the drug conducted by Mayo Clinic and nine other cancer centers in the United States. The cumulative results led to the recent approval of Zevalin by the Food and Drug Administration for treatment of patients with relapsed B cell non-Hodgkin’s lymphoma.

Non-Hodgkin’s lymphoma ranks as the fifth most common type of cancer diagnosed in the United States. However, while incidences of most cancers have been decreasing in the past couple of decades, the number of patients diagnosed with non-Hodgkin’s lymphoma has been steadily increasing.

An estimated 300,000 Americans are currently living with the disease. Most of the patients are age 40 and older. In patients aged 60 years and older, the incidence of non-Hodgkin’s lymphoma is about 100 patients per 100,000 people. Zevalin is manufactured by IDEC Pharmaceuticals Corporation.