The GIA EC50 defined here against 3D7 clone parasites (69.7 μg/ml anti-3D7 AMA1 IgG) was also in agreement with previous reports for the AMA1-C1 vaccine tested in malaria-naive adults.7,36,42,43 Similar to avidity, the antibody isotype profiles were largely comparable across all regimens, with IgG1 and IgG3 the main isotypes induced against AMA1. The gene discussed is IGHG3; the disease is malaria.