This is a Phase II, open-label study designed to To evaluate the safety and efficacy of NM8074 in reducing proteinuria relative to baseline in IgAN patients after 99 days of treatment.

The proposed study, NM8074-IgAN-601, will enroll a planned total of 10 patients as subjects for the trial. All subjects will be administered 17 mg/kg of NM8074 intravenously every week, for a total of 15 doses from Day 1 to Day 99 of the Treatment Period.

Inclusion Criteria:

• Male and female patients ≥18 years of age at the time of consent.
• A body mass index (BMI) within the range of 15 - 38 kg/m2. BMI = Body weight (kg) / [Height (m)]2.
• Confirmation of IgA Nephropathy verified by biopsy performed within the previous three years.
• 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. MenB meningococcal serogroup B vaccine (Bexsero®) will be administered per local guidelines.
• Hemoglobin ≥ 10g/dL and platelet count ≥ 100,000/mm3
• Female and male participates must agree to use contraceptives

Exclusion Criteria:

• Evidence of severe urinary obstruction or difficulty in voiding; any urinary tract disorder other than IgAN at screening and before dosing with NM8074.
• Require dialysis or plasma exchange within 12 weeks prior to screening.
• Presence of crescent formation in ≥50% of glomeruli assessed on renal biopsy.
• History of bone marrow, hematopoietic stem cells, or solid organ transplantation.
• Use of other investigational drugs at the time of enrolment, or within 5 half-lives of enrolment or within 3 months to study day 1 whichever is longer.
• Severe concurrent co-morbidities not amenable to active treatment, e.g., patients with severe kidney disease (CKD stage 4, chronic dialysis).
• Clinically significant abnormal ECG during screening.
• 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.
• Clinically significant medical or psychological conditions or risk factors that, as per the Investigator's judgment, could hinder the patient's participation in the study, introduce additional risks for the patient, or complicate the evaluation of the patient or study outcomes.
• Pregnant, planning to become pregnant, or nursing female subjects.
• Females with a positive pregnancy test result at Screening or on Day 1.