Background of CMV infection in hematopoietic stem cell transplantation (HSCT)<\/strong><\/h1><\/div>\n\n\n\n<\/div>\n\n\n\nLearn about:<\/strong><\/p>\n\n\n\n\n- Any level of CMV is associated with an increased risk of mortality<\/a><\/li>
- Early CMV reactivation association with mortality<\/a><\/li><\/ul><\/div>\n\n\n\n<\/div>\n\n\n\n
CMV R+ hematopoietic stem cell transplant (HSCT) recipients are at increased risk for cytomegalovirus (CMV) infection, disease, and associated mortality1-3<\/sup><\/h2><\/div>\n\n\n\n<\/div>\n\n\n\nCMV serostatus of the recipient is the strongest predictor of CMV infection post-HSCT. Positive CMV serostatus pre-HSCT is a major risk factor of CMV infection and disease.1,4<\/sup><\/p>\n\n\n\n- CMV reactivation has been shown to occur in ~30-65% of CMV-seropositive allogeneic HSCT patients.5,6,a<\/sup><\/li>
- More than 30% of HSCT patients who were CMV-seropositive or had a seropositive donor had CMV infection within 1 month post-transplant.2<\/sup><\/li><\/ul><\/div>\n\n\n\n<\/div>\n\n\n\n
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(a) Results from two retrospective studies Teira et al and Sousa et al.
<\/em><\/p>\n\n\n\n\n<\/span>Any level of CMV viremia is associated with increased risk of mortality in the first year post-HSCT2,b<\/sup><\/strong><\/span><\/p><\/blockquote><\/div>\n\n\n\nCMV viral load as a time-dependent risk factor for overall mortality 1 year after HSCT (n=926)2,b<\/sup><\/strong><\/h3><\/div>\n\n\n\n\n<\/div>![\"Overall](\"https:\/\/www.merckconnect.com\/prevymis\/wp-content\/uploads\/sites\/88\/2026\/03\/CAT_CMV_Viral_Load_As_Time-Dependent-Risk_Graph_2b178d.svg\")
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CI, confidence interval; HR, hazard ratio.
(b) Results from a large, retrospective, noninterventional cohort study of previously collected CMV viral load and clinical outcome measures (n=926).2<\/sup><\/em>
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<\/span>Early CMV reactivation is associated with increased non-relapse mortality and reduced overall survival following allogeneic HSCT6<\/sup><\/strong><\/span><\/p><\/blockquote><\/div>\n\n\n\n\n\n\n\n<\/div>![\"Overall](\"https:\/\/www.merckconnect.com\/prevymis\/wp-content\/uploads\/sites\/88\/2026\/03\/CAT_PREVYMIS-clinical-data-background-relative-risk.svg\")
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\n<\/div>![\"AML,](\"https:\/\/www.merckconnect.com\/prevymis\/wp-content\/uploads\/sites\/88\/2026\/03\/CAT_PREVYMIS-clinical-data-background-cmv-reactivation_8e22e3.svg\")
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Adapted from a CIBMTR analysis by Teira et al.<\/em>
ALL, acute lymphoblastic leukemia; AML, acute myeloid leukemia; CIBMTR, Center for International Blood and Marrow Transplant Research; CML, chronic myeloid leukemia; MDS, myelodysplastic syndrome.<\/em><\/p>\n\n\n\n<\/div>\n\n\n\nStudy design<\/strong><\/h3><\/div>\n\n\n\n<\/div>\n\n\n\n- Retrospective, multivariate analysis of 9,469 patients from the Center for International Blood and Marrow Transplant Research (CIBMTR) database who received their first allogeneic HSCT between 2003 and 20106<\/sup><\/li>
- Multivariable analysis of risk factors for outcomes depending on CMV serostatus and reactivation with hematologic disease relapse, non-relapse mortality, and overall survival (AML [n=5,310], ALL [n=1,883], CML [n=1,079], and MDS [n=1,197])6<\/sup><\/li><\/ul><\/div>\n\n\n\n<\/div>\n\n\n\n
Study limitations<\/strong><\/h3><\/div>\n\n\n\n- No data was collected on how CMV reactivation was monitored with respect to tests used and values applied for implementing preemptive therapy.6<\/sup><\/li>
- Institutional practices for preemptive and prophylactic therapy vary with respect to initiation and duration of therapy, affecting the ability to assess efficacy of initial therapy and duration of CMV reactivation.6<\/sup><\/li>
- The retrospective nature of the analysis limits generalization of results across transplant settings.6<\/sup><\/li><\/ul><\/div>\n\n\n\n<\/div>\n\n\n\n
Learn about:<\/strong><\/p>\n\n\n\n\n CMV serostatus of the recipient is the strongest predictor of CMV infection post-HSCT. Positive CMV serostatus pre-HSCT is a major risk factor of CMV infection and disease.1,4<\/sup><\/p>\n\n\n\n <\/p>\n\n\n\n (a) Results from two retrospective studies Teira et al and Sousa et al. <\/span>Any level of CMV viremia is associated with increased risk of mortality in the first year post-HSCT2,b<\/sup><\/strong><\/span><\/p><\/blockquote><\/div>\n\n\n\n <\/p><\/figcaption><\/figure><\/div>\n\n\n\n CI, confidence interval; HR, hazard ratio. <\/p>\n\n\n\n <\/span>Early CMV reactivation is associated with increased non-relapse mortality and reduced overall survival following allogeneic HSCT6<\/sup><\/strong><\/span><\/p><\/blockquote><\/div>\n\n\n\n\n <\/p><\/figcaption><\/figure><\/div>\n<\/div>\n\n\n\n <\/p><\/figcaption><\/figure><\/div>\n<\/div>\n<\/div>\n<\/div><\/div><\/div>\n\n\n\n Adapted from a CIBMTR analysis by Teira et al.<\/em>CMV R+ hematopoietic stem cell transplant (HSCT) recipients are at increased risk for cytomegalovirus (CMV) infection, disease, and associated mortality1-3<\/sup><\/h2><\/div>\n\n\n\n
<\/em><\/p>\n\n\n\n\nCMV viral load as a time-dependent risk factor for overall mortality 1 year after HSCT (n=926)2,b<\/sup><\/strong><\/h3><\/div>\n\n\n\n\n
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(b) Results from a large, retrospective, noninterventional cohort study of previously collected CMV viral load and clinical outcome measures (n=926).2<\/sup><\/em>
<\/em><\/p>\n\n\n\n<\/picture><\/picture>
ALL, acute lymphoblastic leukemia; AML, acute myeloid leukemia; CIBMTR, Center for International Blood and Marrow Transplant Research; CML, chronic myeloid leukemia; MDS, myelodysplastic syndrome.<\/em><\/p>\n\n\n\nStudy design<\/strong><\/h3><\/div>\n\n\n\n
Study limitations<\/strong><\/h3><\/div>\n\n\n\n