New Treatments for Non-Hodgkin's Lymphoma Patients

Wahl,, M.D., director of nuclear medicine/positron emission tomography (PET) at Johns Hopkins University School of Medicine (Baltimore, MD,USA).

A 2001 pivotal study in which 60 patients who had been treated with and had failed to respond or responded weakly to many types of chemotherapy and whose tumors had returned, received one course of treatment with a radioactive antibody or "smart drug” injected in the bloodstream that targets and destroys cancer cells, according to Dr. Wahl. Of these patients, 65% responded to treatment; 20% had complete response or no evidence of remaining tumors. In the preliminary report, those total responders involved a period of over 47 months. Four years later, the updated study showed that those patients who achieve a total response had "an enduring response,” noted Dr. Wahl, suggesting that "while we can't say the patients are ‘cured,' they have lived without the disease recurring for a substantial period of their lives.”

With this therapy, patients received an injected test dose of the anti-tumor monoclonal antibody, tositumomab and iodine 1-131 tositumomab, to determine how an individual body processes the tagged antibody. Nuclear imaging scans evaluated how rapidly the drug reached the tumor and how quickly radiation disappeared from the body.

Results were even more exciting using tositumomab and iodine-131 tositumomab (Bexxar) earlier in the course of the disease before many of the chemotherapeutic agents have failed. Early in 2005, the use of this therapy used in previously untreated patients with non-Hodgkin's lymphoma was shown to have a 95% response rate.

In another study, researchers evaluated a new type of radioimmunotherapy that uses a humanized monoclonal antibody against the CD22 tumor marker expressed by non-Hodgkin's lymphoma cells. They used a certain antibody that mostly consisted of human material to deliver a powerful radioisotope because the internalizing characteristics of the antibody are especially suited to selectively localizing the radiation in the lymphoma cells, according to this study.