{"classes":[{"categories":[{"measurements":[{"groupId":"OG000","value":"7"}]}],"title":"Anti-romiplostim neutralizing antibodies"},{"categories":[{"measurements":[{"groupId":"OG000","value":"4"}]}],"title":"Transient anti-romiplostim neutralizing antibodies"},{"categories":[{"measurements":[{"groupId":"OG000","value":"1"}]}],"title":"Anti-eTPO neutralizing antibodies"},{"categories":[{"measurements":[{"groupId":"OG000","value":"1"}]}],"title":"Transient anti-eTPO neutralizing antibodies"}],"denoms":[{"counts":[{"groupId":"OG000","value":"203"}],"units":"Participants"}],"description":"Blood samples were first tested for the presence of binding antibodies to romiplostim or the peptide portion of romiplostim, and to endogenous thrombopoietin (eTPO). Samples testing positive for binding antibodies were then tested for neutralizing antibodies by assessing their ability to neutralize romiplostim and/or eTPO in a cell-based bioassay.\n\nParticipants who developed neutralizing antibodies are those who had a postbaseline positive result with a negative or no result at baseline. Transient is defined as a negative result at the participant's last time point tested within the study period.","groups":[{"description":"Participants received romiplostim administered weekly by subcutaneous injection for up to 3 years. The starting dose was 1 µg/kg titrated in 1 µg/kg increments up to a maximum of 10 µg/kg to reach a target platelet count ≥ 50 x 10⁹/L.","id":"OG000","title":"Romiplostim"}],"paramType":"COUNT_OF_PARTICIPANTS","populationDescription":"Participants who received at least 1 dose of romiplostim and with a post-baseline antibody result.","reportingStatus":"POSTED","timeFrame":"Week 12, week 52 and every 24 weeks thereafter up to month 36","title":"Number of Participants Who Developed Anti-Romiplostim or Anti-Thrombopoietin Neutralizing Antibodies","type":"SECONDARY","unitOfMeasure":"Participants"}