{"classes":[{"categories":[{"measurements":[{"groupId":"OG000","value":"4"}]}],"title":"Preexisting"},{"categories":[{"measurements":[{"groupId":"OG000","value":"11"}]}],"title":"Treatment-emergent"}],"denoms":[{"counts":[{"groupId":"OG000","value":"176"}],"units":"Participants"}],"description":"Number of participants under each ADA positive category. A participant is counted as 'Treatment-Emergent' if there is a positive post-baseline sample while the baseline sample is ADA negative, or there is a positive post-baseline sample with a titer \\>= 4-fold of the baseline titer while the baseline sample is ADA positive. A participant is counted as 'Preexisting' if the baseline sample is ADA positive and the participant is not qualified for 'Treatment-Emergent'. If the participant was discontinued from study treatment earlier than one year from the first dose, additional samples will be collected if last ADA is positive.\n\nBaseline is defined as the last value on or before the first dose of study drug.","groups":[{"description":"Starting dose of 1.0 mg/kg subcutaneous injection every 3 weeks (21 days; Q3W). Dose levels can be increased in a stepwise manner beyond the starting dose to 1.33 mg/kg, and up to a maximum of 1.75 mg/kg.","id":"OG000","title":"Luspatercept"}],"paramType":"COUNT_OF_PARTICIPANTS","populationDescription":"Safety Population (all participants who were randomized and received at least one dose of treatment) with baseline and at least one post-baseline immunogenicity assessment result. - Luspatercept Arm Only.","reportingStatus":"POSTED","timeFrame":"Day 1 on week 4, 10, 16, 22, and every 12 weeks (±14 days) from the 24-Week MDS Assessment visit for up to one year from the first dose","title":"Number of Participants With a Positive Anti-drug Antibody (ADA) Test","type":"SECONDARY","unitOfMeasure":"Participants"}