Complement Inhibition
Ravulizumab
Ravulizumab (or Ultomiris) is an intravenous infusion that is administered every 8 weeks in the long term. The first 2 doses are given 2 weeks apart. Ravulizumab blocks the activation of complement and therefore protects the PNH cells from destruction or stimulation.
Ravulizumab works in the same way as Eculizumab, the structure of the drug has been changed to create a longer-lasting treatment. As soon as Ravulizumab therapy is stopped, complement will become active and the PNH cells that were previously protected will be vulnerable to complement attack again. It is therefore usual that Ravulizumab is a treatment that needs to be given lifelong.
Ravulizumab has been proven to reduce the symptoms experienced in PNH and has been shown to improve people’s quality of life.
It also reduces the risks of many of the complications of PNH, such as thrombosis, renal failure or pulmonary hypertension (high blood pressure in the lungs).
Ravulizumab remains in the body for longer than Eculizumab so is, therefore, the preferred treatment option for patients outside a clinical trial who require complement inhibitor.
PNH patients who were on Eculizumab have now been offered to switch to Ravulizumab if suitable, and this rollout process is ongoing.
Eculizumab
Eculizumab (or Soliris) is an intravenous infusion that is administered every 2 weeks in the long term. Eculizumab blocks the activation of complement and therefore protects the PNH cells from destruction or stimulation. As soon as Eculizumab therapy is stopped, complement will become active and the PNH cells that were previously protected will be vulnerable to complement attack again. It is therefore usual that Eculizumab is a treatment that needs to be given lifelong.
Eculizumab has been proven to reduce the symptoms experienced in PNH and has been shown to improve people’s quality of life. It also reduces the risks of many of the complications of PNH, such as thrombosis, renal failure or pulmonary hypertension (high blood pressure in the lungs). It has also therefore improved life expectancy in certain groups of patients with PNH.
Pegcetacoplan
Pegcetacoplan is a C3 inhibitor, and thus considered a proximal complement inhibitor. It is currently approved for patients experiencing Anaemia after 3 months on Eculizumab or Ravulizumab. It is given by a subcutaneous infusion twice a week at home.
In the clinical trials, patients on Eculizumab who were anaemic had an improvement of their haemoglobin by 3.8g/dl. Pegcetacoplan has been proven to reduce symptoms experienced in PNH, and also improve the anaemia caused by extravascular haemolysis.
Your PNH team will discuss whether you are eligible for treatment.