It is important for patients to understand the goals of treatment and to participate in treatment decisions. Treatment aimed at producing complete remissions will likely be different from treatment that is intended to manage symptoms and blood counts. Before embarking on treatment, be sure to understand the goals, the track record of the drugs being used, and their side effects.

Drugs used in treating CLL are administered either as single agent therapies or as combination therapies. Most physicians agree that complete remissions are more likely with combination therapies than with single agents. The rationale to combination therapy is to use drugs that work at different parts of the cell's metabolic processes, thereby increasing the likelihood that more cancer cells will be killed. In addition, the toxic side effects of chemotherapy may be reduced when drugs with different toxicities are combined; each at a lower dose than would be needed if one drug were used alone.

A number of drugs are used in the treatment of CLL. Following are examples of these drugs and the categories to which they belong. Where possible, the generic name is shown first followed, in parenthesis, by the trade name (capitalized) and any common names.

Alkylating agents - For many years, the standard first-line chemotherapy treatment for CLL has been the use of alkylating agents such as chlorambucil (Leukeran), cyclophosphamide (Cytoxan), and busulfan (Myleran).

Corticosteroids - Corticosteriods, such as prednisone (Deltasone), are generally used in conjunction with other drugs such as chlorambucil. They have also been evaluated as single agent therapies. When used as single agents, decreases in node, liver, and spleen enlargement commonly occur, but complete responses are rare.

Purine analogues - Perhaps best known in this category is the drug fludarabine phosphate (Fludara, FAMP). Historically, fludarabine has been used primarily as a second-line therapy, after the initially used alkylating agent (chlorambucil or cyclophosphamide) stopped showing a satisfactory response. More recently, based on impressive test results, fludarabine has gained significant ground as a first line therapy, particularly in the US. Examples of other purine analogues used in the treatment of CLL are cladribine (Leustatin, 2-chlorodeoxyadenosine, 2CdA), pentostatin (Nipent, 2-deoxycoformycin), and compound 506U78 (AraG).

Antitumor antibiotics - These drugs are antibiotic chemotherapy agents, as opposed to antibiotics that work against bacteria. Antiluekemic chemotherapy agents in this category include drugs such as doxorubicin (Adriamycin) and mitoxantrone (Novantrone).

Monoclonal antibodies (Mab or MoAb) - Monoclonal antibodies are another method of treatment that, on theoretical grounds, promises to improve our ability to control CLL. One example is alemtuzumab (Campath-1H), an anti-CD52 monoclonal antibody that is toxic to all lymphocytes and which may be effective in producing remissions in patients who have failed prior therapies, including fludarabine. Another monoclonal antibody is rituximab (Rituxan, IDEC-C2B8), which is active against cells expressing CD20. Rituximab is also in clinical studies currently in conjunction with fludarabine and cyclophosphamide. Zevalin, a 90Y labelled anti-CD20 monoclonal antibody, is the radioactive form of rituximab. Tositumomabiodine (Bexxar) is another radioactive anti-CD20 monoclonal antibody. It is combined with radioactive iodine 131, which delivers lethal radioactivity to cancer cells and also flags them for destruction by the immune system.

Growth Factors and Cytokines - Growth factors are used to stimulate the production of different types of blood cells. Filgrastim (Neupogen, G-CSF), a granulocyte stimulating factor, epoitin alfa (Epogen, Procrit), a red cell stimulating factor, and thrombopoeitin, a platelet stimulating factor are examples of growth factors.

The following table summarizes many of the drugs that are used in the treatment of CLL, some of which are still in clinical trials and not yet approved for general use: