ECULIZUMAB treats certain blood conditions that can cause low levels of red blood cells (
anemia) and blood clots, such as atypical hemolytic uremic syndrome (aHUS) and
paroxysmal nocturnal hemoglobinuria (
PNH). It works by slowing down an overactive immune system, which reduces the breakdown of red blood cells. It also prevents blood cells (platelets) from forming a clot. It may also be used to treat a condition that causes muscles to easily weaken or
fatigue (
myasthenia gravis).