BCX9930 for the Treatment of Paroxysmal Nocturnal Hemoglobinuria (PNH) in Participants With Inadequate Response to C5 Inhibitor Therapy

Inclusion Criteria: * Male or female, aged ≥ 18 years old * Body weight ≥ 40 kg * Documented diagnosis of PNH * Currently being treated with a stable C5 inhibitor regimen * Documentation of current vaccinations against Neisseria meningitidis and Streptococcus pneumoniae or willing to start vaccination series * At screening: PNH clone size of ≥ 10% and hemoglobin ≤ 10.5 g/dL Exclusion Criteria: * Known history of or existing diagnosis of hereditary complement deficiency * History of hematopoietic cell transplant or solid organ transplant or anticipated candidate for transplantation * Myocardial infarction or cerebrovascular accident within 30 days prior to screening, or current and uncontrolled clinically significant cardiovascular or cerebrovascular condition * History of malignancy within 5 years prior to the screening visit * Active bacterial, viral, or fungal infection or any other serious infection within 14 days prior to screening * Treatment with anti-thymocyte globulin within 180 days prior to screening * Initiation of treatment with an erythrocyte or platelet growth factor, or danazol within 28 days prior to screening * Receiving iron supplementation with an unstable dose in the 28 days prior to screening