Safety, Tolerability, Pharmacokinetic, and Pharmacodynamic Study in Healthy Male and Female Subjects and Safety, Tolerability, Pharmacokinetics, and Pilot Efficacy Biomarkers in Subjects With Cold Agglutinin Disease

Inclusion Criteria21

• Healthy female or male subjects who, at the time of screening, are between the ages of 18 and 65 years, inclusive.
• Females will not be pregnant or lactating, and females of childbearing potential and males will agree to use contraception.
• Body mass index of 18.0 to 32.0 kg/m\^2, inclusive; and a total body weight \> 50 kg up to a maximum of 110 kg.
• Study subjects must have received a quadrivalent meningococcal conjugate vaccine (meningococcal serogroups A, C, W, and Y) within the past 5 years or vaccination a minimum of 14 days prior to initial study drug administration.
• The subject must be capable of understanding the investigational nature, potential risks and benefits of the study and capable of providing valid informed consent.
• Female or male subjects who, at the time of screening, are at least 18 years of age with a total body weight of ≥ 50 kg.
• Females will not be pregnant or lactating, and females of childbearing potential and males will agree to use contraception.
• The subject must be capable of understanding the investigational nature, potential risks and benefits of the study and capable of providing valid informed consent.
• The subject must be willing to return to the study center for study treatment and study-related follow-up procedures as required by the protocol.
• Study subjects must have received a quadrivalent meningococcal conjugate vaccine (meningococcal serogroups A, C, W, and Y) within the past 5 years or vaccination a minimum of 14 days prior to initial study drug administration.
• The Participant Identification Center (PIC) site will have provided evidence that the PIC site used to confirm diagnosis of Cold Agglutinin Disease (CAD)
• Primary Cold Agglutinin Disease (CAD) or CAD secondary to active lymphoid or other hematologic malignancy (Cold Agglutinin Syndrome).
• Hemoglobin level \< 105 gram per liter (g/L).
• Bilirubin level above the normal reference range.
• Diagnosis of any other malignancy except for adequately treated basal or squamous cell skin cancer, curatively treated in situ disease, or other cancer from which the subject has been disease-free for ≥ 5 years.
• Clinically relevant infection of any kind within the month preceding enrollment (example, active hepatitis C, pneumonia).
• Clinical diagnosis of Systemic Lupus Erythematosus (SLE), other autoimmune disorders, or ANA titer \> 1:160 at Screening.
• Positive hepatitis panel and/or positive HIV (Human Immuno Deficiency) test. Subjects whose results are compatible with prior immunization may be included at the discretion of the investigator.
• Positive HIV antibody at Screening.
• Treatment with an investigational drug within 90 days or five half-lives preceding the first dose of IP (whichever is longer), with the exception of subjects who received GL-0719 in this study in Cohort 8, who cannot be re-enrolled in Cohort 9 within 60 days after their last dose of GL-0719.
• Concurrent plasma exchange therapy.