New Weapons in the War on Can... Video Transcript

Participants

, Leo I. Gordon MD, Russell J. Schilder MD

Summary

Targeted therapies—treatments that zero in on cancerous cells—are among the current treatments for fighting cancer. One type of targeted therapy, monoclonal antibodies, has made great progress in recent years. Find out how scientists developed these treatments and how they can offer new hope to people with cancer.

Webcast Transcript

ANNOUNCER: Non-Hogdkin's lymphoma, or NHL, is a white blood cell cancer of the lymphatic system. Over 50,000 new cases are expected to be diagnosed this year in the U.S. At a Gilda's club gathering in Chicago, lymphoma patients, and those who wanted to learn about the disease, found out about current treatment options.

LEO GORDON, MD: When we use the radioisotopes, we're giving it this way, and it goes out.

DONALD MECCIA, MD: I have three family members who have lymphoma, including my mother and as a doctor, my interest levels have been quite high, and I must suggest that this program tonight has been exemplary.

PAT BASHAW: There are people who are actively seeking out treatments that hopefully at some point will be curative. I feel certain, that eventually it will happen.

ANNOUNCER: One of the latest treatments discussed was Zevalin, a new type of treatment that contains a monoclonal antibody. But what are monoclonal antibodies? And how do they work?

RUSSEL SCHILDER, MD: Monoclonal antibodies are substances that our body normally makes to fight infections or in response to other foreign attack that our immune system makes. And normally our body makes a whole lot of different antibodies to different things, each cell making one type of antibody.

LEO GORDON, MD: Cancer investigators took advantage of that and attempted to make specific antibodies against certain targets on malignant cells. Most of those targets were proteins or antigens on the surface of the those cells. So the concept was if you could take an antibody, target it directly to the protein or antigen on the surface of the cancer cell, you could then cause that cell to stop growing, cause that cell to die and it's led to a host of new treatments for malignancies.

ANNOUNCER: Because they specifically fight one protein on a cancer cell, monoclonal antibodies are called targeted therapies. And the list of those available as treatment options in cancer, is growing.

RUSSEL SCHILDER, MD: The first one was rituximab in the treatment of lymphoma. That was followed quickly by a drug called Herceptin®, which is used in the treatment of breast cancer. Another one that's commonly referred to as Campath® in the treatment of chronic lymphocytic leukemia.

ANNOUNCER: All monoclonal antibodies used in medicine originate from mice. When used in humans, these mouse antibodies cause an immune response known as HAMA, human anti-mouse antibodies. This HAMA response can produce side effects in patients and reduce the effectiveness of the treatment.

LEO GORDON, MD: You're introducing a foreign protein, mostly a mouse protein, into a human system. So patients experience fevers, chills, sometimes a drop in blood pressure, sometimes wheezing, all the kinds of things that you might expect as a reaction to a foreign protein.

Another concern is that, again as a foreign mostly mouse protein, we know that the human body can elicit an immune response to the antibody. And so that if you have an injection of a mouse protein, within a month or two you might be making antibodies against that mouse protein, thereby limiting its effectiveness down the road.

ANNOUNCER: In an attempt to reduce the problems associated with HAMA, scientists have, in some cases, been able to replace large portions of the mouse antibody with human antibody.

LEO GORDON, MD: As we develop antibodies that are more of human origin, I think we'll see that those side effects become less.

ANNOUNCER: Despite some concerns, monoclonal antibodies are still seen as a more tolerable treatment than chemotherapy.

RUSSEL SCHILDER, MD: Most people think of chemotherapy as, whether people lose their hair, they have nausea and vomiting.