{"denoms":[{"counts":[{"groupId":"OG000","value":"0"}],"units":"Participants"}],"description":"CMV DNA sequence analysis to be performed only in subjects with CMV reactivation. Resistance to letermovir will be monitored by retrospective genotypic analysis of the CMV terminase genes in CMV DNA extracts from selected plasma samples collected at the time of diagnosed CMV reactivation. Samples will be analyzed by standard population sequencing technology through an established contract laboratory with validated protocols in place.","groups":[{"description":"Beginning within 7 days of the first administration of standard alemtuzumab, patients receive letermovir PO (or IV over 1 hour if patient is unable to take PO for an extended period of time) daily on days 1-28. Cycles repeat every 28 days for up to 3 months after the last dose of alemtuzumab in the absence of unacceptable toxicity.\n\nLetermovir: Given PO","id":"OG000","title":"Treatment (Letermovir)"}],"populationDescription":"Data for this outcome was not collected","reportingStatus":"POSTED","timeFrame":"Up to 2 years","title":"Genotyping of Mutations in CMV Terminase Complex Genes","type":"OTHER_PRE_SPECIFIED"}