A Study of Maribavir in Japanese People With Cytomegalovirus (CMV) Infection

The confirmed viremia clearance was defined as a plasma CMV DNA concentration below the lower limit of quantification (LLOQ) (that is [i.e.], less than [<] 34.5 international units per milliliter [IU/mL]) when assessed by the COBAS® 8800/COBAS® CMV Test, in two consecutive post-baseline samples, separated by at least 5 days. To be considered a responder for the primary endpoint, the participant must have received exclusively study-assigned treatment (regardless of whether study-assigned treatment was completed).

A TEAEs was defined as any event emerging or manifesting at or after the initiation of treatment with an investigational product or medicinal product or any existing event that worsened in either intensity or frequency following exposure to the investigational product or medicinal product. An SAE was any untoward medical occurrence or effect that at any dose resulted in death, was life-threatening, required inpatient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability / incapacity, was a congenital anomaly / birth defect or was medically important due to other reasons than the above mentioned criteria.

The number of participants with TEAEs leading to maribavir study treatment discontinuation (including treatment interruption or withdrawal) were reported.

Vital sign assessments included blood pressure, pulse, respiratory rate and body temperature. Any clinically meaningful change in vital signs which were deemed clinically significant by the investigator were reported.

Physical examination included assessments of the head, eyes, ears, nose, throat, neck, lymph nodes, and the cardiovascular, dermatological, musculoskeletal, respiratory, gastrointestinal, genitourinary, and neurological systems. Any clinically meaningful change in physical examination which were deemed clinically significant by the investigator were reported.

Clinical laboratory parameters included evaluations of hematology, chemistry, urinalysis. Any clinically meaningful change in clinical laboratory parameters which were deemed clinically significant by the investigator were reported.

12-lead ECG were evaluated. Any change in ECG assessments which are deemed clinically meaningful by the investigator were reported.

Immunosuppressant drug concentration testing was solely for participants who received immunosuppressive therapy with tacrolimus, cyclosporine, or everolimus. The number of participants with an increased level of at least one immunosuppressant drug was reported.

New onset of acute or chronic GVHD assessed as TEAEs, and graft rejection, or graft loss assessed were reported.

The confirmed viremia clearance was defined as a plasma CMV DNA concentration below the LLOQ (i.e., <34.5 IU/mL) when assessed by the COBAS® 8800/COBAS® CMV Test, in two consecutive post-baseline samples, separated by at least 5 days. Percentage of participants who maintained combined CMV viremia clearance and CMV infection symptom control at Week 8 Through Weeks 12, 16 and 20 were reported.

Time to first confirmed viremia clearance was defined as time from the start date of first dose of study treatment to the date of confirmed viremia clearance (event), or the date of last CMV DNA assessment on study before the initiation of alternative anti-CMV treatment (censored). The time to first confirmed CMV viremia clearance was calculated as date of first confirmed CMV viremia clearance - randomization date + 1). The date of first confirmed CMV viremia clearance was the date of first of two consecutive samples with plasma CMV DNA <LLOQ that meet the criteria of confirmed CMV viremia clearance.

Recurrence of confirmed CMV viremia was defined as plasma CMV DNA concentration greater than or equal to (>= 34.5 IU/mL) LLOQ when assessed by the COBAS® 8800/COBAS®CMV Test in 2 consecutive plasma samples at least 5 days apart, after achieving confirmed viremia clearance.

The change from baseline in plasma CMV viral load, i.e., plasma CMV DNA concentration was assessed and reported.

Recurrence of CMV viremia was defined as plasma CMV DNA concentration >= lower limit of quantification (LLOQ, i.e. >=34.5 IU/mL) when assessed by COBAS® 8800/COBAS® CMV Test in 2 consecutive plasma samples at least 5 days apart, after being unquantifiable (<LLOQ, i.e. <34.5 IU/mL) for at least 5 days in 2 consecutive samples during the first 8 weeks of the study. Study Treatment: The first stipulated 8 weeks treatment. Follow up period: period started after completion of stipulated 8 weeks treatment to Week 20. While on study assigned treatment: period over which participants received actual dosing regardless of stipulated 8 weeks completion (Week 8 or earlier). While off study assigned treatment: period after study treatment, regardless of stipulated 8 weeks completion (Week 8 or earlier up to Week 20).

Plasma samples were obtained and tested to identify mutations in the viral UL97 and UL54 genes confer resistance to maribavir. Percentage of participants with any mutations in the CMV genes conferring resistance to maribavir was reported.

The confirmed CMV viremia clearance at Week 8 was defined as plasma CMV DNA concentrations <137 IU/mL, in 2 consecutive post-baseline samples separated by at least 5 days, regardless of whether study treatment was discontinued before the end of the stipulated 8 weeks of therapy.

Cmin (pre-dose) of maribavir was assessed.