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Biological therapies use naturally occurring substances
produced by the immune system. These substances may kill lymphoma
cells, slow their growth, or may activate the patient's immune system
to more effectively fight the lymphoma.
Immunotherapy with monoclonal antibodies
Antibodies are normally produced by the immune system to help
fight infections. Monoclonal antibodies designed to attack lymphoma
cells are made in the laboratory.
Rituximab (Rituxan) is the most widely used monoclonal
antibody for lymphoma. Rituximab specifically recognizes and attaches
to a protein that is found on the surface of lymphoma cells called
CD20. This attachment tells the lymphoma cell to die. Patients receive
rituximab by infusion into a vein (IV) at the oncologist's office or
clinic. Side effects during the infusion are very common, and include
chills, fever, nausea, rashes, fatigue, and headaches. Unlike regular
chemotherapy, rituximab does not cause low blood counts or hair loss.
This treatment is one of the standard treatments for lymphoma and
Waldenstrom macroglobulinemia (WM). Rituximab can be given alone or
with regular chemotherapy as a part of treatment.
Alemtuzumab (Campath): Another monoclonal antibody, called
alemtuzumab (Campath), is directed at a different protein on lymphoma
cells called CD52. This drug is more commonly used to treat patients
with chronic lymphocytic leukemia, but it has also helped some patients
with WM. A serious side effect of alemtuzumab is a large drop in the
blood counts that can last weeks. People on this drug can develop
life-threatening infections that are hard to treat while their white
blood cells are low.
Immunomodulating agents
The drug thalidomide is used to treat multiple myeloma, and
can also help some WM patients. A problem with this drug is that many
patients have trouble tolerating the side effects that occur when
higher doses of thalidomide are used (such as when it is used alone).
Side effects of thalidomide include drowsiness, fatigue, severe
constipation, and neuropathy (painful nerve damage). The neuropathy can
be severe, and may not go away after the drug is stopped. There is also
an increased risk of serious blood clots that start in the leg and can
travel to the lungs. Because thalidomide causes severe birth defects if
it is taken during pregnancy, it can only be obtained through a special
program run by the drug company that makes it. The best results with
thalidomide in WM occurred when it was given along with other drugs,
such as rituximab or dexamethasone.
Lenalidomide (Revlimid) is a newer drug similar to
thalidomide. It is often used to treat multiple myeloma. In studies of
patients with WM, the patients showed improvement in their IgM and
beta-2-microglobulin levels, but developed worsening anemia. The role
of this drug in treating WM is still being explored. The most common
side effects of lenalidomide are thrombocytopenia (low platelets) and
low white blood cell counts. The risk of blood clots is not as high as
that seen with thalidomide, but it is still elevated. Like thalidomide,
access to lenalidomide is also tightly controlled out of concern about
possible serious birth defects.
Interferon is a hormone-like protein naturally produced by
white blood cells to help the immune system fight infections. Some
studies have suggested that interferon can cause some lymphoma tumors
to shrink. Side effects of this treatment include moderate to severe
fatigue, fever, chills, headaches, muscle and joint aches, and mood
changes. It is still not certain whether interferon is the best
treatment for some patients who have non-Hodgkin lymphoma or WM. It is
usually used only in patients who continue to get sicker after
treatment with standard chemotherapy drugs.
Last Medical Review: 08/04/2009 Last Revised: 08/04/2009
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