14th International Medical Education Workshop on Molecular Targeted Therapy of Cancer (MTTC)

Monoclonal antibodies and targeting them against cancer cells in lymphoma

Prof Ronald Levy - Stanford University, USA

It began some time ago when we learned about the ability to make antibodies, monoclonal antibodies, and target them against cancer cells. So we chose a target which is unique to the cancer cells in lymphoma and it was a customised target where every patient needed their own unique and different antibody. We did that and it was very successful but it became difficult to do on a mass wide basis in a pharmaceutical product. So instead of that another target was chosen which is on the cancer cells but also on normal cells of the same type and that became known as rituximab. Rituximab targets the tumour and also the normal B-lymphocytes. So we didn’t know in the beginning that that would be safe; it turned out to be safe and rituximab turned out to be a blockbuster drug used around the world, now every patient with lymphoma gets this drug in addition to the other therapies they also can get.

Could you talk about your current research?

So what we’ve done now is take it to the next level where we make the antibody work better and treat the cancer even more efficiently by using a second antibody against the cell that does the killing. So when rituximab goes in the body it finds the cancer cells and the normal lymphocytes, binds to them and marshals the immune system to come and kill it, kill the target. So we can talk to the immune system with another antibody now and activate it and get it to kill even better. So we can take in the animal model therapy which is partially effective, rituximab alone, and with a second antibody against the immune system we can cure the animals. So now in the clinic we have clinical trials going on and the first patients’ results are just in and they look extremely promising.

Why was rituximab unsuccessful?

It is successful, it has a limited success. It makes tumours shrink, it extends people’s lives, makes them live longer but in most instances doesn’t cure the patient permanently. So we think we can turn this into a curative therapy, but not only rituximab for lymphoma but also Herceptin for breast cancer and cetuximab for colon cancer and every other antibody that targets cancer cells that is going to be produced by the industry with a single second antibody against the immune system we think we can make them all work better, maybe all become curative therapies rather than partially effective therapies. It’s already in patients and we’re already seeing the first results and they’re looking, as I said, extremely promising. I think the future will be to reduce the need for chemotherapy, with all the side effects that it has, and enhance the immune system to do part of the job, if not all of the job, in treating cancer. So my goal is to eventually eliminate chemotherapy and replace it with what the immune system can do.