New radioactive-tipped antibodies battle non-Hodgkin's lymphoma

Health Canada has approved two new "smart" drugs to treat low-grade non-Hodgkin's lymphoma, a cancer that kills about 3,000 Canadians a year.

The drugs, Zevalin and Bexxar, are part of a class of medications known as radio-immunotherapy. They harness the body's immune system to attack cancer while zapping the tumour cells with sharply targeted radiation.

Monoclonal antibodies are part of a new generation of "smart" cancer therapies.

Scientists inject human cancer cells in mice, which then produce antibodies against these cells. The antibodies are harvested from the mice and cloned in the lab to produce identical copies. The patient is then infused with the antibodies, stimulating an immune response.

A monoclonal antibody, rituximab, has been used for a number of years to treat non-Hodgkin's lymphoma. Zevalin and Bexxar, however, are tipped with a kind of radioactive warhead, making them doubly effective.