About Campath® (alemtuzumab)
Campath is a recombinant DNA-derived humanized monoclonal antibody (Campath-1H) that is directed against the 21-28 KD cell surface glycoprotein, CD52. CD52 is expressed on the surface of normal and malignant B and T lymphocytes, NK cells, monocytes, macrophages, and tissues of the male reproductive system. The Campath-1H antibody is an IgG1 kappa with human variable framework and constant regions, and complementarity-determining regions from a murine (rat) monoclonal antibody (Campath-1G).
Mechanism of Action
Campath® (alemtuzumab) binds to CD52, a non-modulating antigen that is present on the surface of essentially all B and T lymphocytes, a majority of monocytes, macrophages, and NK cells, and a subpopulation of granulocytes. Analysis of samples collected from multiple volunteers has not identified CD52 expression on erythrocytes or hematopoietic stem cells.
The proposed mechanism of action is antibody-dependent lysis of leukemic cells following cell surface binding. Campath-1H Fab binding was observed in lymphoid tissues and the mononuclear phagocyte system. A proportion of bone marrow cells, including some CD34+ cells, express variable levels of CD52. Significant binding was also observed in the skin and male reproductive tract (epididymis, sperm, seminal vesicle). Mature spermatozoa stain for CD52, but neither spermatogenic cells nor immature spermatozoa show evidence of staining.
Campath is indicated as a single agent for the treatment of B-cell chronic lymphocytic leukemia (B-CLL).
WARNING: CYTOPENIAS, INFUSION REACTIONS, and INFECTIONS
Cytopenias: Serious, including fatal, pancytopenia/marrow hypoplasia, autoimmune idiopathic thrombocytopenia, and autoimmune hemolytic anemia can occur in patients receiving Campath. Single doses of Campath greater than 30 mg or cumulative doses greater than 90 mg per week increase the incidence of pancytopenia [see WARNINGS AND PRECAUTIONS (5.1)].
Infusion Reactions: Campath administration can result in serious, including fatal, infusion reactions. Carefully monitor patients during infusions and withhold Campath for Grade 3 or 4 infusion reactions. Gradually escalate Campath to the recommended dose at the initiation of therapy and after interruption of therapy for 7 or more days [see DOSAGE AND ADMINISTRATION (2) and WARNINGS AND PRECAUTIONS (5.2)].
Infections: Serious, including fatal, bacterial, viral, fungal, and protozoan infections can occur in patients receiving Campath. Administer prophylaxis against Pneumocystis jiroveci pneumonia (PCP) and herpes virus infections [see DOSAGE AND ADMINISTRATION (2.2) and WARNINGS AND PRECAUTIONS (5.3)].
The most commonly reported adverse reactions are infusion reactions fever, chills, hypotension, urticaria, nausea, rash, tachycardia, dyspnea), cytopenias (neutropenia, lymphopenia, thrombocytopenia, anemia), and infections (CMV viremia, CMV infection, other infections). In clinical trials, the frequency of infusion reactions was highest in the first week of treatment. Other commonly reported adverse reactions include vomiting, abdominal pain, insomnia and anxiety. The most commonly reported serious adverse reactions are cytopenias, infusion reactions, and immunosuppression/infections. See "Warnings and Precautions," and "Adverse Reactions" sections of full Prescribing Information.
Please see Full Prescribing Information (PDF).
