How it is administered

Alemtuzumab is given as an intravenous (IV) infusion. For blood cancers, such as B-cell chronic lymphocytic leukemia (B-CLL), it is typically administered over 2 hours. The dose is gradually increased to a maximum of 30 mg per infusion, given three times per week for up to 12 weeks. Each dose is prepared by diluting the medication in a bag of sterile saline or dextrose solution, and it is not given as a quick injection or bolus. Premedication with antihistamines and acetaminophen is recommended to reduce infusion-related reactions.

Alemtuzumab is available as a clear, colorless solution in single-use vials for IV use only.

How it works

Alemtuzumab is a monoclonal antibody that targets a protein called CD52, which is found on the surface of certain immune cells, including B and T lymphocytes, monocytes, macrophages, and some granulocytes. By binding to CD52, alemtuzumab marks these cells for destruction by the body's immune system through mechanisms such as antibody-dependent cellular cytolysis and complement-mediated lysis.

This action leads to a rapid and profound depletion of lymphocytes, which can help control diseases where these cells are abnormal or cancerous, such as B-CLL. The reduction in these immune cells can also suppress the immune system, which is why infections and other immune-related side effects are possible. The effects on lymphocyte counts can last for months after treatment, and recovery of the immune system may take a significant amount of time.

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 considered for adults with this type of blood cancer, especially if other treatments have not been effective or are not suitable.

While alemtuzumab is not specifically approved for Adult T-cell Leukemia/Lymphoma (ATLL), it is sometimes used off-label in blood cancers where CD52 is present on the malignant cells. The decision to use alemtuzumab should be made by a hematologist or oncologist experienced in treating blood cancers.

Who should not take it

Alemtuzumab should not be used in patients who have a known hypersensitivity or severe allergic reaction to alemtuzumab or any of its ingredients. It is also contraindicated in patients with active infections, including HIV, due to the risk of further suppressing the immune system and causing serious or life-threatening infections.

Patients with severe, ongoing infections or who are severely immunocompromised should not receive alemtuzumab. Live viral vaccines should not be given during or soon after treatment, as the immune system may not be able to respond appropriately.

Commonly used with

Alemtuzumab is often used with supportive medications to reduce side effects and prevent infections. These include:

• Antihistamines and acetaminophen before each infusion to reduce infusion reactions
• Antiviral and antibiotic prophylaxis (such as trimethoprim/sulfamethoxazole for PCP prevention and famciclovir for herpes virus prevention)
• Sometimes, corticosteroids are used to manage infusion reactions

It is not typically combined with other chemotherapy agents during the same treatment course for B-CLL.

Commonly tested with

Alemtuzumab has been tested in combination with other chemotherapy agents in clinical trials for blood cancers, but its primary use is as a single agent. It may be studied alongside other immunosuppressive or cytotoxic drugs in research settings, but in clinical practice, it is most often used alone with supportive care medications.