What’s new in Hodgkin disease research and treatment?
Important research into Hodgkin disease is being done right now in many university hospitals, medical centers, and other institutions around the world. Scientists are getting closer to finding out what causes the disease and how to improve treatment.
In recent years, PET scans and combined PET/CT scans have been found to be very helpful in determining the extent of Hodgkin disease in the body and in assessing how well treatment is working. PET scans are now commonly used early in the course of treatment to help doctors decide how much treatment needs to be given.
In general, cure rates for Hodgkin disease are high, but long-term side effects of treatment are an important issue. A very active area of research is directed at learning which patients can be treated with gentler therapy and which patients need stronger treatment.
A related area of research is finding less-toxic treatments that do not have serious long-term side effects, yet still cure as many patients as possible. New chemotherapy combinations of as many as 10 different drugs are being studied. The reasoning behind this approach is that even though more drugs are needed, by using less of each drug, fewer side effects may occur. Another approach is using drugs that better target Hodgkin disease cells, as opposed to chemotherapy drugs. Some of these are described below.
The same is true for radiation therapy. Doctors are looking to see which patients might do just as well with lower doses of radiation, or even no radiation. Doctors are also studying whether newer forms of radiation therapy, such as intensity-modulated radiation therapy (IMRT) and proton therapy, might be useful in Hodgkin disease. These approaches focus radiation more precisely on tumors, which limits the doses reaching nearby normal tissues.
New chemotherapy drugs and drug combinations are being studied in patients with Hodgkin disease. Some drugs, such as vinorelbine, idarubicin, bendamustine, and gemcitabine, which are already used to treat other cancers, have shown promise against Hodgkin disease that has relapsed after other chemotherapy treatments. Studies are in progress to see if these drugs could be more effective than the ones now in use.
Newer drugs that work differently from typical chemotherapy drugs are now being studied as well. These are known as targeted therapy drugs.
For example, a class of drugs known as mTOR inhibitors has shown some promise in early clinical studies against relapsed Hodgkin disease. Drugs called histone deacetylase (HDAC) inhibitors, such as panobinostat, have also shown some early promise.
Other drugs being studied include lenalidomide (Revlimid®) and bortezomib (Velcade®). These drugs are more often used to treat multiple myeloma and some non-Hodgkin lymphomas, but they may prove to be useful in Hodgkin disease as well.
Some newer targeted drugs, such as PLX3397, affect tumor cells other than the lymphoma cells themselves. These other cells actually make up much of the Hodgkin disease tumors and are thought to help the lymphoma cells grow. Research on these types of drugs is still early.
Antibodies are proteins normally made by the immune system to help fight infections. Each antibody attacks only a specific target (usually a protein on the surface of an unwanted cell). Monoclonal antibodies are man-made versions of these immune system proteins. Some can kill cancer cells by themselves. Others have radioactive molecules or cell poisons attached to them, which help kill the cancer cells. An advantage of these drugs is that they seem to target lymphoma cells while having fewer side effects than chemotherapy drugs. They may be used alone or combined with chemotherapy.
Some monoclonal antibodies, such as brentuximab vedotin (Adcetris™) and rituximab (Rituxan®), are already being used to treat Hodgkin disease (see “Monoclonal antibodies for Hodgkin disease”), while others are now being studied.
Hodgkin disease cells have the CD30 molecule on their surface, which is the target of brentuximab vedotin and several other monoclonal antibodies, including XmAb2513.
The cells in the nodular lymphocyte predominant type of Hodgkin disease often have the CD20 antigen, which is the target of rituximab. Studies are now being done to see if rituximab can help treat classic forms of Hodgkin disease as well.
Tositumomab (Bexxar®) is an anti-CD20 antibody that is attached to a radioactive molecule. When injected into the blood, the antibody brings the radiation directly to the lymphoma cells. This drug is used to treat some types of non-Hodgkin lymphoma, but studies are in progress to see if it might also help treat Hodgkin disease.
Last Medical Review: 12/10/2012
Last Revised: 01/18/2013