Eculizumab (pronounced E-cloo-zee-mab) is a monoclonal antibody that reduces haemolysis by blocking the complement activation process. As described here, complement has nine levels of activation, referred to as the complement cascade. The antibody interrupts the complement activation by binding to the complement at level 5. This fools the body into thinking that the blood cells contain the missing protein and allows the red blood cells to survive.
C1 -- -- -- C5 -- -- -- C9 less intense ------------------ most intense ↑
Eculizumab blocks complement at C5
Eculizumab is administered intravenously every 14 days and although a relatively new treatment, it has been very successful for patients with moderate to severe PNH. The treatment reduces symptoms significantly and in many cases haemoglobin levels are maintained without the need for blood transfusions.
Treatment with Eculizumab has been associated with an increased risk of contracting a severe meningococcal infection. This may occur because the part of the complement system that is blocked by Eculizumab is important in the control of this particular bacterial infection. However, the risk is still very low.
Patients must receive an effective meningococcal vaccine prior to commencing treatment with Eculizumab.
The most common, less serious side effects associated with Eculizumab are:
Generally, the side effects resolve within a few weeks of commencing Eculizumab, but as with PNH, each patient’s experience is unique.
PLEASE NOTE: PNH presents differently in each individual, therefore the above information may not be directly applicable to your circumstances. You should always discuss appropriate treatment options with your treating haematologist. This information is general and provided as a summary to increase knowledge and awareness of issues patients may wish to address with their medical practitioners.
Disclaimer: This information has been prepared by members of the PNHSAA Inc and has been checked for accuracy by practitioners experienced with PNH. The PNHSAA Inc does not guarantee its accuracy, it is intended as general information only and not to be substituted for medical advice. Please consult your medical practitioner for further information regarding your personal circumstances.