Active safety surveillance
Toxicity
ABSCESSES, ADVERSE EVENT FOLLOWING IMMUNIZATION
Designated safety medical doctors actively followed-up participants who reported a potential adverse event following immunization (AEFI) through the questionnaires or by notification of the study team. Reactions of grade 1 or 2 severity (as per the Food and Drug Administration (FDA) Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials)Photographs of potential injection site abscesses, keloid scars, and unusual local reactions were reviewed by safety medical doctors at regular quality and safety team meetings for consensus decision on classification and whether any local clinical follow-up was required.