Its products include eculizumab (Soliris) and ravulizumab (Ultomiris), both used to treat the rare disorders of atypical hemolytic uremic syndrome (aHUS) and paroxysmal nocturnal hemoglobinuria (PNH); asfotase alfa (Strensiq), used to treat hypophosphatasia; sebelipase alfa (Kanuma), used to treat lysosomal acid lipase deficiency, and andexanet alfa (Andexxa), used to stop life threatening or uncontrollable bleeding in people who are taking rivaroxaban or apixaban.

Soliris was tested as a treatment option because of its effectiveness in treating atypical hemolytic uremic syndrome, an illness similar to that caused by the EHEC infection.

[22][23] In July 2020, the company agreed to pay more than $21 million to settle claims that it bribed government officials in Turkey and Russia to gain approval for its drugs.

[28] In December 2011, Alexion acquired Montreal-based Enobia Pharma, the developer of asfotase alfa, a drug used to treat the genetic disorder hypophosphatasia, for as much as $1.08 billion.

[29] In June 2015, Alexion acquired Synageva, a maker of rare disease treatments, in an $8.4 billion stock-and-cash deal.

[36][37][38] In January 2020, the company acquired Achillion Pharmaceuticals for $930 million, boosting its immune system disease pipeline.