A Study of Letermovir (MK-8228) to Evaluate Efficacy and Safety for Prevention of Cytomegalovirus Infection in Chinese Hematopoietic Stem Cell Transplant Recipients (MK-8228-045)

The key inclusion and exclusion criteria include but are not limited to the following:

Inclusion Criteria

• Male/Female Chinese adult participant of an allogeneic Hematopoietic Stem Cell Transplant (HSCT).
• Has documented positive Cytomegalovirus (CMV) serostatus (CMV immunoglobulin G [IgG] seropositive) for recipient (R+) at the time of screening.
• Is receiving a first allogeneic HSCT.
• Is within 28 days post-HSCT at the time of randomization.
• Female participant is not a Woman of Child Bearing Potential (WOCBP) or is a WOBCP who agrees to use acceptable contraception during the treatment period and for ≥28 days after the last dose of study drug.

Exclusion Criteria

• Received a previous allogeneic HSCT.
• Has a history of CMV end-organ disease within 6 months prior to randomization.
• Has evidence of CMV viremia at any time from HSCT procedure until the time of randomization.
• Has severe hepatic insufficiency.
• Is a) on renal replacement therapy (e.g., hemodialysis, peritoneal dialysis) OR b) has end stage renal impairment with a creatinine clearance <=10 mL/min within 5 days prior to randomization.
• Has both moderate hepatic insufficiency AND moderate to severe renal insufficiency.
• Has an uncontrolled infection on the day of randomization.
• Has rapidly progressing disease that requires mechanical ventilation or is hemodynamically unstable.
• Has a documented positive result for a human immunodeficiency virus antibody (HIV-Ab) test at any time prior to randomization, or for hepatitis C virus antibody (HCV-Ab) with detectable HCV ribonucleic acid (RNA), or hepatitis B surface antigen (HBsAg) within 90 days prior to randomization.
• Has active solid tumor malignancies except localized basal cell or squamous cell skin cancer or the condition under treatment (e.g., lymphomas).
• Has received any prohibited medications within 2 days prior to initiation of treatment with Letermovir.
• Is anticipated to be treated with Traditional Chinese Medicine or herbal medicine during the study treatment period and for 14 days after study medication.