Biological therapy The drugs used in biological therapy are laboratory-made versions of substances that occur naturally in your body. Their built-in ability to influence the growth of normal cells is cleverly redirected to fight your cancer cells.
How does it work? Certain substances in your body promote the growth of cells. Others work to get rid of cells. In biological therapy, artificially produced versions of these naturally occurring substances are used to slow, stop or destroy cancer cells.
What are monoclonal antibodies? Cancer cells develop from normal cells. As a result, it can be hard for the body’s immune system to identify cancer cells and fight against them. Artificially produced monoclonal antibodies are designed to recognise certain proteins on the surface of cancer cells and attach themselves to those cells. Some monoclonal antibodies trigger your immune system to attack cancer cells and some stop cancer cells from multiplying. Others simply act like taxis, carrying other drugs or radiation directly to the cancer cells they are supposed to target. Monoclonal antibodies are delivered to you through a drip that goes directly into the bloodstream.
What is immunotherapy? Immunotherapy involves stimulating the immune system to fight cancer cells more effectively. The most common treatment is interferon, a protein that occurs naturally in your body in small amounts. During immunotherapy, you are given injections of synthetically produced interferon to strengthen your immune system. Immunotherapy is most likely to be used in the treatment of kidney cancers, but it is also used for some skin cancers, leukaemias and myelomas.
What are growth blockers? Cancer cells need to make new blood vessels in order to grow and spread. Certain drugs used in biological therapy can stop the growth of cancer by blocking the production of blood vessels in cancer cells; they’re called angiogenesis inhibitors. The spread of cancer cells also relies on signals from certain chemicals that occur naturally in the body. Other drugs used in biological therapy hinder the growth of cancer by blocking those signals; they’re called cancer growth inhibitors. Angiogenesis inhibitors and cancer growth inhibitors can be delivered as injections under the skin, through drips into the bloodstream, or as pills.
What are growth inhibitors? Growth factors, sometimes called colony stimulating factors, are naturally occuring chemicals that control the growth of cells in your body. Granulocyte-colony stimulating factor (G-CSF) is a protein that stimulates your bone marrow to produce a particular kind of white blood cell that can help your immune system to recognise and attack cancer cells. The use of growth factors in biological therapy is still at an early stage.
Words to know
Angiogenesis inhibitors drugs that block the production of new blood vessels in cancer cells
Cancer growth inhibitors drugs that block cancer cells from receiving signals that trigger growth
Granulocyte-colony stimulating factor (G-CSF) a protein that stimulates the growth of white blood cells
Immune system the body’s natural defences
Immunotherapy the use of drugs to stimulate the immune system
Leukaemia cancer of the white blood cells
Monoclonal antibodies a type of synthetic antibody used in biological therapy
Myeloma cancer of plasma cells
Things to ask
What are the side effects? When you’re having biological therapy, particularly if it involves interferon, you could end up feeling like you’re battling a flu with chills, fevers, aching muscles and fatigue. You could also find yourself prone to bruising, bleeding and infections. If you’re having G-CSF injections you could feel aches in your bones. Your care team can give you some idea of what to expect, based on what kind of biological therapy you’re having.
Expert's insight: Keith Cox Keith Cox, a nurse practitioner at Sydney Cancer Centre, says that side effects are usually fairly minimal with biological therapy. However, it’s difficult to generalise as there so many different types of biological drugs around – and many more are being trialled.
“Some of the biological therapies are in oral format and some are infusions via a drip. Sometimes you might get skin rashes and facial rashes around the scalp and around the neck. We don’t say to the patient, ‘That’s a good sign you’ve got a rash’, but it’s often a good indication that they’re actually responding to the therapy.
“With some of the monoclonal antibodies you don’t get the rash, but you can get a lowering of blood pressure while it’s being infused – this could make you feel a bit dizzy.
“Sometimes people get flu-like symptoms during or after their infusions. [But] biological therapies are a lot better tolerated and have less side effects than chemotherapy.
“MabThera [rituximab] is a monoclonal antibody used for lymphoma. It’s given in small doses over a long period of time, increasing the dose as the infusion goes on. It’s done at the same time as chemotherapy and can take four to six hours.”
More help
Cancer Council Helpline 13 11 20 Cancer Council Helpline is a free, confidential telephone information and support service run by Cancer Councils in each state and territory. Specially trained staff are available to answer your questions about cancer and offer emotional or practical support. You can call from anywhere in Australia for the cost of a local call. The Helpline is open between 9am and 5pm, Monday to Friday (some states have extended hours).
Photo by Eamon Gallagher
RUAIRI MAHER Irishman Ruairi Maher was married in 2010. Ten days later, he was diagnosed with follicular non-Hodgkin’s lymphoma.
Ruairi was immediately booked in for chemotherapy and a biological treatment called rituximab, which is administered over several hours through a drip into a vein. Allergic reactions are common and Ruairi’s run-in with rituximab was no exception.
But there was some good news. Five days after his first cycle of treatment, the 34 year old discovered his wife was pregnant.
“I had fear going into the treatment, especially the chemotherapy. It’s not a head cold, if you know what I mean. It was explained to me that the rituximab was a drug used in combination with the chemotherapy, and was standard treatment for follicular non-Hodgkin’s lymphoma.
“The first time I took rituximab, my face and scalp broke out in a rash about 20 minutes into it. My wife noticed it immediately, so they gave me some Phenergan, a drug which treats allergies. They also stopped the treatment and let the rash go down which took about 15 minutes. Then they started up the rituximab again, but this time they used a smaller dosage. I was warned that my allergic reaction could happen again.
“For the following treatments, I received an amount of Phenergan before we started and that used to make me quite sleepy. The following treatments I pretty much slept through because of the Phenergan.
“After six cycles of the treatment, I had a CT scan and my oncologist told me that my cancer had gone to sleep. Rituximab had locked the disease, it kept the lymphoma cells asleep. I’m now in the maintenance program where I’ll be taking rituximab once every three months for two years.
“I asked why the program went for only two years, and was told that because it’s a relatively new treatment, they’re not sure of the long-term consequences. At this stage, I’m just happy it’s available.”