Drugs commonly used in CLL: (This is a partial list to be expanded)
Campath (Alemtuzumab)
Campath is a monoclonal antibody somewhat like rituximab (see below). It attaches to a cell
marker called CD52, and causes cell death. The CD52 marker is found on all lymphocytes, as well as cells in the male
genital tract.
Because B and T lymphocytes can be depleted with Campath, care must be taken to avoid infection.
Prophylatic use of antibiotics and anti-viral drugs are often used along with Campath.
Chlorambucil (Leukeran)
Chlorambucil is another
alkylating agent. It interfers with DNA, causing cell death. Chlorambucil will lower the number of blood cells in circulation.
Chlorambucil is an older drug that still has a place in treating CLL. Because side
effects are often more mild than other chemotherapy drugs, it may be prescribed to elderly patients. However, serious
side effects can occur from the use of the drug.
There is a low percentage of persons who
have acomplete response to the drug.
Cyclophosphamide (Cytoxan)
Cyclophosphamide is widely used anti-neoplastic drug. It is classified as a
alkylating agent. These type of
drugs interfere with the normal functioning of DNA. This leads to cell death as the damage to the DNA is too severe to repair.
Dividing cells are more susceptible to this type of damage, so it can be effective in treating various cancers.
Fludarabine
(Fludara)
Fludarabine is a drug that inhibits DNA synthesis. This causes
cell death.
Fludarabine can be used as a single agent or in combination with other drugs. It shows
significant activity as a single agent. In clinical trials, fludarabine gives a
more than 50% objective response
rate in both treatment-naive and pre-treated patients.
Fludarabine can cause significant side effects, including severe bone marrow
suppression.
Recovery times can last up to one year. There can be other significant side effects as well.
Methlyprednisolone
(Solu-Medrol)
Methlyprednisolone is a synthetic steroid. It is a potent anti-inflammatory
drug, and is sometimes used in combination with other chemotherapeutic drugs in treating CLL. Currently, it is
undergoing clinical trials in combination with rituximab.
Rituximab (Rituxan, MabThera)
Rituximab is one of the class of monoclonal antibodies. These are manufactured antibodies that are identical to one
another. Antibodies work by attaching to cells.
Rituximab has been designed to
attach to the CD20 cell marker generally found on B lymphocytes, including CLL cells. Because this marker is found on
normal B-lymphocytes as well as CLL cells, administration of rituximab will
result in the depletion of normal as well
as malignant cells.
Since CLL cells frequently do not have large numbers of CD20 markers on their cell membranes
(dim expression), normal doses of the drug as a single agent in CLL have been disappointing. Rituximab can be used as
a monotherapy, but doses are generally greater than those used in other malignancies such as
non-Hodgkin's lymphoma.
Rituximab can also be used in combination with other drugs. In experiments at MD Anderson, rituximab has been given
along with fludarbine and cyclophosphamide. The results of clinical trials with that regime (FCR) have
been impressive,
leading to a significant number of complete remissions as well as molecular remissions (CLL cells cannot be detected with
the most sensitive tests).
