What’s New in Research and Treatment of Castleman Disease?
Research into the causes and treatment of Castleman disease (CD) is being done in many medical centers throughout the world. Unfortunately, research into this disease is slowed by the fact that CD is rare.
Doctors have learned a great deal about some of the possible causes of CD in recent years. For example, many people with multicentric CD (MCD) have been found to have evidence of infection with human herpesvirus-8 (HHV-8) in their lymph nodes. This type of information might help researchers come up with new ways of treating this disease.
But there’s a lot we still don’t know about the exact causes of CD. This is now under study.
Researchers have begun to study several promising new drugs for use against CD in recent years.
Many patients with MCD have too much of a protein called interleukin-6 (IL-6) in their blood. Drugs that target IL-6 have shown promise against MCD. One of these drugs, siltuximab, is a monoclonal antibody that binds to IL-6, which stops it from reaching lymphocytes. This drug is now approved for use in people with MCD who are not infected with HIV or HHV-8 (see “Immunotherapy for Castleman disease”).
Another monoclonal antibody, tocilizumab (Actemra®), blocks the action of IL-6 by binding to its receptor on lymphocytes. This drug is being studied for use against MCD. It is already approved to treat rheumatoid arthritis in the United States, and some doctors use it to treat MCD as well.
It is unclear how helpful these drugs will be in MCD patients who are HIV-positive, since few HIV-positive patients have been in the studies so far. Still, these drugs offer hope for the future treatment of MCD.
Other drugs being studied for treatment of CD include:
- Sirolimus, cyclosporine, and mycofenolate mofetil: These drugs suppress the immune system, so they are often used in autoimmune diseases or to help prevent the rejection of organ transplants, but they may also be helpful in CD.
- Suramin: This drug is thought to work by stopping IL-6 from attaching to and affecting lymphocytes.
- Bortezomib (Velcade): This drug is used mainly to treat multiple myeloma, but some reports also suggest it might help some people with CD.
- CX-4945: This drug blocks CK2, a protein that helps some cells grow and divide. It is still in the earliest phases of testing.
Last Medical Review: July 7, 2014 Last Revised: May 23, 2016