This was a multicenter, prospective, open-label, non-controlled study to assess the efficacy and safety of an IV dose of 2 g/kg of IGIV-C in subjects with MG exacerbations.

The study consisted of a single dose course of IGIV-C treatment followed by 28-days of post-infusion assessments. The total duration of study participation for each subject was up to 28 ± 2 days. Approximately 50 subjects, ages 18 or greater, were planned to be enrolled in the study and receive a single, total dose of 2 g/kg of IGIV-C over 2 consecutive days (dose of 1 g/kg per day) across multiple centers in Argentina, Canada, Europe, and South Africa.

Inclusion Criteria:

• Was male or female aged ≥18 years.
• Subjects must be willing and able to provide written informed consent (if applicable, a legally authorized representative may provide informed consent on behalf of the subject).
• Subjects who met the clinical criteria for diagnosis of MG with an exacerbation defined as worsening of MG symptoms as defined by an Myasthenia Gravis Foundation of America (MGFA) classification IVb or V.
• Subjects on long-term (8 weeks) corticosteroid treatment for MG.
• Female subjects of child-bearing potential must have a negative test for pregnancy (human chorionic gonadotropin [HCG]-based assay).
• Subjects must be willing to comply with all aspects of the clinical trial protocol, including blood sampling and long-term storage of extra samples, for the entire duration of the study.

Exclusion Criteria:

• Subjects who had received immune globulin treatment given by IV, subcutaneous or intramuscular route within the last 30 days.
• Subjects with documentation of a lack of clinical response to intravenous immunoglobulin (IVIg) therapy for MG.
• Subjects documented positive for antibodies directed against Muscle specific kinase (MuSK).
• Subjects with corticosteroid (CS) treatment initiated within the last 8 weeks or modified within the last 2 weeks.
• Subjects with plasma exchange (PLEX) within the last 30 days.
• Subjects with MG exacerbation attributable to change in medication or infection or evident infection as defined by, but not limited to, the presence of at least one of the following diagnostic features: 1) axillary temperature ≥38°C, 2) positive blood culture of infective microorganism, 3) white blood cell count >12×10^9/L and differential white blood cell count of >10% band neutrophils (>1.2×10^9/L), and 4) pulmonary infiltrate with consolidation on chest X-ray. Alternatively, other signs and symptoms may be considered for the diagnosis of evident infection according to the Investigator's judgement.
• Subjects with inadequate venous access.
• Subjects with a history of anaphylactic reactions or severe reactions to any blood-derived product.
• Subjects with a history of intolerance to any component of the investigational products.
• Subjects with a documented diagnosis of thrombotic complications to polyclonal IVIG therapy in the past.
• Subjects with a history of recent (within the last year) myocardial infarction, stroke or uncontrolled hypertension.
• Subjects who suffered from uncontrolled congestive heart failure, embolism or documented electrocardiogram (ECG) changes indicative of myocardial ischemia or atrial fibrillation.
• Subjects with current known hyperviscosity or hypercoagulable state.
• Subjects currently receiving anti-coagulation therapy.
• Subjects with a history of chronic alcoholism or illicit drug abuse (addiction) in the 12 months preceding the Baseline Visit.
• Subjects currently receiving, or having received within 3 months prior to the Baseline Visit, any investigational medicinal product or device.
• Subjects with a known Immunoglobulin A (IgA) deficiency and anti-IgA serum antibodies.
• Subjects with renal impairment (i.e., serum creatinine exceeds more than 1.5 times the upper limit of normal [ULN] for the expected normal range for the testing laboratory).
• Subjects with aspartate aminotransferase (AST) or alanine aminotransferase (ALT) levels exceeding more than 2.5 times the ULN for the expected normal range for the testing laboratory.
• Subjects with haemoglobin levels <9 g/dL.