How it is administered

Alemtuzumab is given as an intravenous (IV) infusion. For the treatment of B-cell chronic lymphocytic leukemia (B-CLL), it is typically administered over 2 hours. The dosing schedule involves gradually increasing the dose to a maximum of 30 mg per day, given three times a week for up to 12 weeks. Premedication with an oral antihistamine and acetaminophen is recommended before each dose to help reduce infusion-related reactions.

How it works

Alemtuzumab is a monoclonal antibody that targets a protein called CD52, which is found on the surface of B and T lymphocytes (types of white blood cells), as well as on some other immune cells. By binding to CD52, alemtuzumab marks these cells for destruction by the body's immune system, leading to their removal from the blood. This process is called antibody-dependent cellular-mediated lysis. In chronic lymphocytic leukemia, the abnormal B cells express CD52, so alemtuzumab helps reduce the number of these cancerous cells.

Because alemtuzumab also affects normal immune cells, it can cause a significant reduction in the number of lymphocytes, leading to immunosuppression. This is why patients receiving alemtuzumab are at increased risk for infections and require careful monitoring during and after treatment.

Who Should take it

Alemtuzumab is indicated as a single agent for the treatment of B-cell chronic lymphocytic leukemia (B-CLL). It may be used in patients who have not responded to other treatments or for those who are newly diagnosed and require therapy due to progressive disease.

Your doctor will determine if alemtuzumab is appropriate for you based on your disease stage, previous treatments, and overall health. It is important to discuss your medical history and any other medications you are taking with your healthcare provider before starting alemtuzumab.

Who should not take it

There are no absolute contraindications listed for alemtuzumab in the treatment of B-CLL. However, caution is advised in patients with active infections, as alemtuzumab can further suppress the immune system and increase the risk of serious infections.

Patients who have experienced severe allergic or infusion-related reactions to alemtuzumab or any of its components should not receive this medication. It should also be used with caution in pregnant or breastfeeding women, and in those with significant bone marrow suppression or autoimmune cytopenias.

Commonly used with

Alemtuzumab is often used as a single agent for B-CLL. However, patients are routinely given premedications such as antihistamines (like diphenhydramine) and acetaminophen before each infusion to reduce the risk of infusion-related reactions. Prophylactic antibiotics (such as trimethoprim/sulfamethoxazole for PCP prevention) and antivirals (such as famciclovir for herpes virus prevention) are also recommended during and after treatment to reduce the risk of infections.

Commonly tested with

In clinical studies, alemtuzumab has been compared to other treatments for B-CLL, such as chlorambucil. It is not typically combined with other chemotherapy agents in standard practice for CLL, but ongoing research may evaluate its use in combination with other therapies. Patients receiving alemtuzumab are monitored with regular blood tests to assess blood cell counts and infection risk.