Study of NM8074 in Patients with AHUS with Evidence of Ongoing Thrombotic Microangiopathy

Inclusion Criteria: * Patients ≥ 18 years at the time of consent * Patients with evidence of resistant or relapsed complement-mediated aHUS with symptoms of Thrombocytopenia, hemolysis, ongoing Thrombotic Microangiopathy and acute kidney injury. * Evidence of ongoing Thrombotic Microangiopathy which includes Haptoglobin \<LLN or undetectable and/or presence of schistocytes * Acute kidney injury (proteinuria/creatinuria \> ULN and/or reduced eGFR) * Platelets less than 150,000 per microliter (Thrombocytopenia) * Anemia (Hemoglobin ≤10 g/dL) due to hemolysis * Lactate dehydrogenase (LDH) level ≥ 1.5 times the upper limit of normal (xULN) during Screening * All patients must be vaccinated prior to dosing with MenACWY Menactra® polysaccharide diphtheria toxoid conjugate vaccination against Neisseria meningitidis serogroups A, C, Y, and W-135 and MenB meningococcal serogroup B vaccine (Bexsero®). If the window of vaccination is short, then patients will be prophylactically treated with appropriate antibiotics * Willing and able to understand and complete informed consent procedures, including signing and dating the informed consent form (ICF), and comply with the study visit schedule. * Male patients and partners of child-bearing potential must agree to use contraceptives and male patients must agree to refrain from donating sperm for the duration of the study. * Female partners of child-bearing potential (WOCBP), defined as all women physiologically capable of becoming pregnant, must have a negative pregnancy test at screening and must agree to use highly effective methods of contraception during dosing and for 1 month after stopping the investigational drug. Exclusion Criteria: * History of bone marrow, hematopoietic stem cell, or solid organ transplantation * Treatment with complement blockers * Patients with infections * HUS due to ADAMTS-13 deficiency (\<5%) * Kidney disease other than aHUS * Chronic dialysis (hemo or peritoneal) * Liver disease or other major autoimmune diseases * Typical HUS (Shiga toxin +) * Known Systemic Lupus Erythematosus (SLE), Systemic Sclerosis, or antiphospholipid antibody positivity or syndrome * History of currently active primary or secondary immunodeficiency * Currently active systemic infection or suspicion of active bacterial, viral, or fungal infection within 2 weeks prior to first dose, or history of unexplained, recurrent bacterial infections * Has a currently active or known history of meningococcal disease or N. meningitidis infection * Severe concurrent co-morbidities not amenable to active treatment, e.g., patients with severe kidney disease (CKD stage 4, chronic dialysis) * Females who have a positive pregnancy test result at Screening or on Day 1. * Pregnant, planning to become pregnant, or nursing female subjects.