Ultomiris

Ultomiris is the brand name for ravulizumab-cwvz, a humanized monoclonal antibody that inhibits the terminal complement component C5. It was developed by Alexion Pharmaceuticals, and is marketed by AstraZeneca after the company’s acquisition of Alexion. The drug is indicated for the treatment of certain rare blood disorders, notably paroxysmal nocturnal hemoglobinuria and atypical hemolytic uremic syndrome in eligible patients.

In paroxysmal nocturnal hemoglobinuria, Ultomiris works by blocking C5 to reduce intravascular hemolysis and the associated anemia and fatigue. In atypical hemolytic uremic syndrome, C5 blockade helps prevent thrombotic microangiopathy and protects kidney function by limiting complement-mediated damage. The overall goal is to reduce disease activity and the need for supportive therapies.

Administration and dosing are handled by intravenous infusion. Ultomiris employs a loading regimen followed by maintenance dosing every eight weeks, with the exact dose adjusted for body weight and patient age. The extended eight‑week interval is designed to offer greater convenience compared with earlier C5 inhibitors that required more frequent dosing.

Safety considerations include a heightened risk of meningococcal infections; vaccination against meningococcus is recommended before starting treatment, with additional precautions if vaccination is incomplete. Other possible adverse effects include headache, back pain, upper respiratory infections, and infusion reactions. As with all complement inhibitors, adherence to the dosing schedule is important to maintain disease control and avoid relapse.

Regulatory status: in the United States, approval for PNH was granted in 2019 and for aHUS in 2021; European approvals followed, establishing Ultomiris as a long-acting alternative to first-generation C5 inhibitors.