Safety, Tolerability, Pharmacokinetics and Pharmacodynamics of ANX005 in Participants With Warm Autoimmune Hemolytic Anemia (wAIHA)

Recruitment & Eligibility

Inclusion Criteria

Male or non-pregnant, non-lactating female ≥18 years of age (no maximum age).
Diagnosis of wAIHA at least 3 months prior to screening with a direct antiglobulin test (DAT) ≥1 positive for immunoglobulin G (IgG)±C3, or a diagnosis of mixed autoimmune hemolytic anemia (AIHA) that is DAT positive for both IgG and C3, with a presence of a cold antibody with a thermal amplitude ≥30ºCelcius.
Hemoglobin (Hgb) level ≤10.0 grams/deciliter (pre-transfusion).
Evidence of classical complement pathway activation.
Evidence of active hemolysis.
Stable use of glucocorticoids and immunosuppressants are permitted.
Vaccinations against encapsulated bacterial organisms within 5 years prior to screening or participant must be willing to receive prophylaxis against infections with encapsulated bacteria via vaccination and/or the use of prophylactic antibiotics in accordance with local standards of practice and/or guidelines.

Exclusion Criteria

Elevated aspartate aminotransferase or alanine aminotransferase levels >2.5 times the upper limit of normal.
Platelet count <30 X 10^9/liter.
History of cold agglutinin disease.
History of solid organ, bone marrow, or stem cell transplantation.
History of splenectomy within the 3 months prior to screening.
Received rituximab or other anti-CD20 monoclonal antibody <3 months prior to screening.
Intravenous immunoglobulin (IVIg) treatment within 3 months prior to screening or plasmapheresis or immunoadsorption treatment within 60 days prior to screening.
Clinically significant, recent, or ongoing illness or medical condition, including coexistent autoimmune disorder, malignancy, HIV, hepatitis B virus, and hepatitis C virus.
History of meningitis or septicemia within the past 2 years.
Treatment with an investigational therapeutic agent within 30 days prior to screening.
Hypersensitivity to any drug product or excipients used in this study or to previous IV medication administration.
Body weight less than 50 kilograms (kg) or greater than 100 kg

Study & Design

Arm && Interventions

Group	Intervention	Description
ANX005	ANX005	Participants will receive two once-weekly doses of ANX005 at specific time points

Primary Outcome Measures

Name	Time	Method
Change in disease activity biomarkers	Baseline to Day 71	Change in hemoglobin, lactate dehydrogenase, bilirubin, reticulocyte count and haptoglobin from baseline
Safety: Treatment-emergent adverse events (TEAEs)	Up to Week 16	Number of participants with TEAEs, defined as any adverse event with an onset on or after the day of infusion through 16 weeks after the infusion

Secondary Outcome Measures

Name	Time	Method
Plasma concentrations	Up to Day 71	Plasma concentrations of ANX005 over time
Change in complement system biomarkers	Baseline to Day 71	Change in CH50 and C1q from baseline

Recruitment & Eligibility