Alexion (also known as Alexion, AstraZeneca Rare Disease) is a biopharmaceutical company engaged in therapies for rare diseases. Its products include eculizumab (Soliris) and ravulizumab (Ultomiris) for paroxysmal nocturnal hemoglobinuria and atypical hemolytic uremic syndrome, asfotase alfa (Strensiq) for hypophosphatasia, sebelipase alfa (Kanuma) for lysosomal acid lipase deficiency, and andexanet alfa (Andexxa) for anticoagulant reversal. The company provides these therapies to medical institutions treating rare disease patients worldwide.