PK Study of Gefurulimab SC in Healthy Chinese Adult Participants

Inclusion Criteria: * Participants must be 18 to 45 years of age, inclusive, at the time of signing the informed consent. * Body weight within ≥ 45 kg to \< 110 kg and BMI within the range 18 to 30 kg/m2 (inclusive) at Screening and Admission (Day -1). * Participants who are healthy as determined by medical evaluation with no clinically significant or relevant abnormalities as determined by medical history, physical examination, vital signs, 12-lead ECG, and clinical laboratory evaluation. * QTcF ≤ 450 msec for male participants and ≤ 460 msec for female participants at Screening and prior to dosing on Day 1. * Documented vaccination against N meningitidis serotypes A, C, W-135, Y at least 28 days and not more than 3 years prior to dosing on Day 1. Exclusion Criteria: * History of any Neisseria meningitidis infection. * History or presence of cardiovascular, respiratory, hepatic, renal, gastrointestinal, endocrinological, hematological, or neurological disorders. * Abnormal blood pressure as determined by the Investigator. * History of latent or active TB (Tuberculosis) or exposure to endemic areas. * Active systemic bacterial, viral, or fungal infection within 14 days prior to dosing. * History of latent or active TB or exposure to endemic areas within 8 weeks prior to the Screening Visit confirmed by QuantiFERON®-TB test. * Significant allergies to humanized biologics. * Clinically significant multiple or severe drug allergies, intolerance to topical corticosteroids, or severe post-treatment hypersensitivity reactions. * History of clinically significant allergic reaction (eg, anaphylaxis or angioedema) to any product (eg, food, pharmaceutical). * History of allergy or intolerance to penicillin or cephalosporin. * Lymphoma, leukemia, or any malignancy within the past 5 years except for basal cell or squamous epithelial carcinomas of the skin that have been resected with no evidence of metastatic disease for 3 years. * Current or chronic history of liver disease. * Evidence of human immunodeficiency virus (HIV) infection (positive HIV type 1 or type 2 antibody). * Evidence of hepatitis B infection (positive hepatitis B surface antigen \[HBsAg\] or positive total hepatitis B core antibody \[HBcAb\] with negative surface antibody \[anti-HBs\]), or hepatitis C viral infection (positive HCV RNA). * Female participants who have a positive pregnancy test at Screening or Admission. * Positive prestudy drug/alcohol screen; positive result may be repeated once.