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Letermovir granules

Phase 2

Cytomegalovirus (CMV) Infection | Small molecule | Other |Merck & Company, Inc.|Last Updated: Aug 22, 2024

Success Probability
Approval Probability 71%
TA Base Rate26%
Adjusted LOA41%
ML RiskLOW_RISK
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Market & Valuation
rNPV $3.2B
Market Size $9.4B
Revenue Basis $1.6B
Competitors 6
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Trial Design
UNCONTROLLEDDMC
Total Trials1
Total Enrollment65
FDA Designations
No designations recorded
Clinical Trials (1)
NCT IDTitlePhaseStatusEnrollmentVelocityDesignStartCompletionLast UpdatedSitesCountries
NCT03940586Letermovir Treatment in Pediatric Participants Following Allogeneic Haematopoietic Stem Cell Transplantation (HSCT) (MK-8228-030)PHASE2 COMPLETED 65Aug 8, 2019Aug 25, 2023Aug 22, 202440 United States, Australia +9
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Study Endpoints
Primary Endpoints
Area Under the Concentration-time Curve From Time 0 to 24 Hours Post-dose (AUC0-24) of Plasma Letermovir Taken as Oral Formulation by Ages 2 - <18 Years
Day 7: Pre-dose, 1, 2.5, 8, and 24 hours post-dose

Blood was collected on treatment Day 7 from participants aged 2 - \<18 years in order to determine the AUC0-24 of plasma letermovir for participants receiving oral formulation. Individual values were natural log transformed and evaluated separately with a linear mixed effects model containing a fixed effect for treatment and a random effect for participant. Participants aged \< 2 years were not presented as their data analysis resulted in a different measure type and method of dispersion.

AUC0-24 of Plasma Letermovir Taken as Oral Formulation by Ages 2 to <12 Years
Day 7: Pre-dose, 1, 2.5, 8, and 24 hours post-dose

Blood was collected on treatment Day 7 from participants aged 2 to \<12 years in order to determine the AUC0-24 of plasma letermovir for participants receiving oral formulation. Individual values were natural log transformed and evaluated separately with a linear mixed effects model containing a fixed effect for treatment and a random effect for participant. Participants aged \<2 and \>12 years were not presented as their data analysis resulted in a different measure type and method of dispersion.

AUC0-24 of Plasma Letermovir Taken as Oral Formulation by Ages <2 Years
Day 7: Pre-dose, 1, 2.5, 8, and 24 hours post-dose

Blood was collected on treatment Day 7 from participants aged \<2 years in order to determine the AUC0-24 of plasma letermovir for participants receiving oral formulation. Individual values were natural log transformed and evaluated separately with a linear mixed effects model containing a fixed effect for treatment and a random effect for participant. Participants aged 2 - \<18 years were not presented as their data analysis resulted in a different measure type and method of dispersion. The measure of dispersion is not determined when N \<2.

Maximal Concentration (Cmax) of Plasma Letermovir Taken as Oral Formulation by Ages 2 - <18 Years
Day 7: Pre-dose, 1, 2.5, 8, and 24 hours post-dose

Blood was collected on treatment Day 7 from participants aged 2 - \<18 years in order to determine the Cmax of plasma letermovir for participants receiving oral formulation. Individual values were natural log transformed and evaluated separately with a linear mixed effects model containing a fixed effect for treatment and a random effect for participant. Participants aged \< 2 years were not presented as their data analysis resulted in a different measure type and method of dispersion.

Cmax of Plasma Letermovir Taken as Oral Formulation by Ages 2 to <12 Years
Day 7: Pre-dose, 1, 2.5, 8, and 24 hours post-dose

Blood was collected on treatment Day 7 from participants aged 2 to \<12 years in order to determine Cmax of plasma letermovir for participants receiving oral formulation. Individual values were natural log transformed and evaluated separately with a linear mixed effects model containing a fixed effect for treatment and a random effect for participant. Participants aged \<2 and \>12 years were not presented as their data analysis resulted in a different measure type and method of dispersion.

Cmax of Plasma Letermovir Taken as Oral Formulation by Ages < 2 Years
Day 7: Pre-dose, 1, 2.5, 8, and 24 hours post-dose

Blood was collected on treatment Day 7 from participants aged \<2 years in order to determine the Cmax of plasma letermovir for participants receiving oral formulation. Individual values were natural log transformed and evaluated separately with a linear mixed effects model containing a fixed effect for treatment and a random effect for participant. Participants aged 2 - \<18 years were not presented as their data analysis resulted in a different measure type and method of dispersion. The measure of dispersion is not determined when N \<2

Minimum Concentration of Plasma Letermovir Observed Before Next Dose (Ctrough) Taken as Oral Formulation by Ages 2 - <18 Years
Day 7: 24 hours post-dose

Blood was collected on treatment Day 7 from participants aged 2 - \<18 years in order to determine the Ctrough of plasma letermovir for participants receiving oral formulation. Individual values were natural log transformed and evaluated separately with a linear mixed effects model containing a fixed effect for treatment and a random effect for participant. Participants aged \< 2 years were not presented as their data analysis resulted in a different measure type and method of dispersion.

Ctrough of Plasma Letermovir Taken as Oral Formulation by Ages 2 to <12 Years
Day 7: Pre-dose, 1, 2.5, 8, and 24 hours post-dose

Blood was collected on treatment Day 7 from participants aged 2 to \<12 years in order to determine Ctrough of plasma letermovir for participants receiving oral formulation. Individual values were natural log transformed and evaluated separately with a linear mixed effects model containing a fixed effect for treatment and a random effect for participant. Participants aged \<2 and \>12 years were not presented as their data analysis resulted in a different measure type and method of dispersion.

Ctrough of Plasma Letermovir Taken as Oral Formulation by Ages < 2 Years
Day 7: 24 hours post-dose

Blood was collected on treatment Day 7 from participants aged \<2 years in order to determine the Ctrough of plasma letermovir for participants receiving oral formulation. Individual values were natural log transformed and evaluated separately with a linear mixed effects model containing a fixed effect for treatment and a random effect for participant. Participants aged 2 - \<18 years were not presented as their data analysis resulted in a different measure type and method of dispersion. The measure of dispersion is not determined when N \<2.

AUC0-24 of Plasma Letermovir Taken as Intravenous (IV) Formulation by Ages 12 - <18 Years
Day 7: Pre-dose, 1, 2.5, 8, and 24 hours post-dose

Blood was collected on treatment Day 7 from participants aged 12 - \<18 years in order to determine the AUC0-24 of plasma letermovir for participants receiving IV formulation. Individual values were natural log transformed and evaluated separately with a linear mixed effects model containing a fixed effect for treatment and a random effect for participant. Participants aged \< 12 years were not presented as their data analysis resulted in a different measure type and method of dispersion.

AUC0-24 of Plasma Letermovir Taken as IV Formulation by Ages 2 to <12 Years
Day 7: Pre-dose, 1, 2.5, 8, and 24 hours post-dose

Blood was collected on treatment Day 7 from participants aged 2 to \<12 years in order to determine the AUC0-24 of plasma letermovir for participants receiving IV formulation. Individual values were natural log transformed and evaluated separately with a linear mixed effects model containing a fixed effect for treatment and a random effect for participant. Participants aged \< 2 years and \> 12 years were not presented as their data analysis resulted in a different measure type and method of dispersion.

AUC0-24 of Plasma Letermovir Taken as IV Formulation by Ages <2 Years
Day 7: Pre-dose, 1, 2.5, 8, and 24 hours post-dose

Blood was collected on treatment Day 7 from participants aged \<2 years in order to determine the AUC0-24 of plasma letermovir for participants receiving IV formulation. Individual values were natural log transformed and evaluated separately with a linear mixed effects model containing a fixed effect for treatment and a random effect for participant. Participants aged \> 2 years were not presented as their data analysis resulted in a different measure type and method of dispersion. The measure of dispersion is not determined when N \<2.

Concentration at the End of Infusion (Ceoi) of Plasma Letermovir Taken as IV Formulation by Ages 12 - <18 Years
Day 7: Pre-dose, 1, 2.5, 8, and 24 hours post-dose

Blood was collected on treatment Day 7 from participants aged 12 - \<18 years in order to determine the Ceoi of plasma letermovir for participants receiving IV formulation. As samples were collected outside the collection window Ceoi for these samples were predicted by using a log linear model .Participants aged \< 12 years were not presented as their data analysis resulted in a different measure type and method of dispersion.

Ceoi of Plasma Letermovir Taken as IV Formulation by Ages 2 to <12 Years
Day 7: Pre-dose, 1, 2.5, 8, and 24 hours post-dose

Blood was collected on treatment Day 7 from participants aged 2 to \<12 years in order to determine the Ceoi of plasma letermovir for participants receiving IV formulation. As samples were collected outside the collection window Ceoi for these samples were predicted by using a log linear model. Participants aged \< 2 years and \> 12 years were not presented as their data analysis resulted in a different measure type and method of dispersion.

Ceoi of Plasma Letermovir Taken as IV Formulation by Ages s 2 to <12 Years
Day 7: Pre-dose, 1, 2.5, 8, and 24 hours post-dose

Blood was collected on treatment Day 7 from participants aged 2 to \<12 years in order to determine the Ceoi of plasma letermovir for participants receiving IV formulation. As samples were collected outside the collection window Ceoi for these samples were predicted by using a log linear model. Participants aged \> 2 years were not presented as their data analysis resulted in a different measure type and method of dispersion. A measure of dispersion is not determined when N \<2.

Ceoi of Plasma Letermovir Taken as IV Formulation by Ages <2 Years
Day 7: Pre-dose, 1, 2.5, 8, and 24 hours post-dose

Blood was collected on treatment Day 7 from participants aged \<2 years in order to determine the Ceoi of plasma letermovir for participants receiving IV formulation. As samples were collected outside the collection window Ceoi for these samples were predicted by using a log linear model. Participants aged \> 2 years were not presented as their data analysis resulted in a different measure type and method of dispersion. A measure of dispersion is not determined when N \<2.

Ctrough of Plasma Letermovir Taken as IV Formulation by Ages 12 - <18 Years
Day 7: 24 hours post-dose

Blood was collected on treatment Day 7 from participants aged 12 - \<18 years in order to determine the Ctrough of plasma letermovir for participants receiving IV formulation. Individual values were natural log transformed and evaluated separately with a linear mixed effects model containing a fixed effect for treatment and a random effect for participant. Participants aged \< 12 years were not presented as their data analysis resulted in a different measure type and method of dispersion.

Ctrough of Plasma Letermovir Taken as IV Formulation by Ages 2 to <12 Years
Day 7: 24 hours post-dose

Blood was collected on treatment Day 7 from participants aged 2 to \<12 years in order to determine the Ctrough of plasma letermovir for participants receiving IV formulation. Individual values were natural log transformed and evaluated separately with a linear mixed effects model containing a fixed effect for treatment and a random effect for participant. Participants aged \< 2 years and \> 12 years were not presented as their data analysis resulted in a different measure type and method of dispersion.

Ctrough of Plasma Letermovir Taken as IV Formulation by Ages <2 Years
Day 7: Pre-dose, 1, 2.5, 8, and 24 hours post-dose

Blood was collected on treatment Day 7 from participants aged \<2 years in order to determine the Ctrough of plasma letermovir for participants receiving IV formulation. Individual values were natural log transformed and evaluated separately with a linear mixed effects model containing a fixed effect for treatment and a random effect for participant. Participants aged \> 2 years were not presented as their data analysis resulted in a different measure type and method of dispersion. The measure type is Geometric Mean, and a measure of dispersion is not determined when N \<2.

Ctrough of Plasma Letermovir Taken During Sparse PK for Oral Formulation
Day 7: 24 hours post-dose

Blood was collected on treatment Day 7 in order to determine the Ctrough of plasma letermovir during sparse PK for participants receiving oral formulation. Individual values were natural log transformed and evaluated separately with a linear mixed effects model containing a fixed effect for treatment and a random effect for participant.

Ctrough of Plasma Letermovir Taken During Sparse PK as IV Formulation
Day 7: 24 hours post-dose

Blood was collected on treatment Day 7 in order to determine the Ctrough of plasma letermovir for participants receiving IV formulation during sparse PK. Individual values were natural log transformed and evaluated separately with a linear mixed effects model containing a fixed effect for treatment and a random effect for participant.

Secondary Endpoints
Percentage of Participants With One or More Adverse Event (AE)
Up to Week 48 post-transplant (up to 52 weeks)
Percentage of Participants Who Discontinued Study Medication Due to an AE.
Up to Week 14 post-transplant (up to 18 weeks)
Percentage of Participants With Clinically Significant CMV Infection Through Week 14 Post-transplant
Up to Week 14 post-transplant (up to 18 weeks)
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Study Design & Arms
AllocationNA
MaskingNONE
ModelSINGLE_GROUP
PurposePREVENTION
Treatment Arms
ArmTypeDescription
LetermovirEXPERIMENTALLetermovir administered either orally or intravenously within 28 days post-transplant, once daily through week 14 (approximately 100 days). Dosing will vary based on age, weight, and whether participant takes cyclosporin A as a concomitant medication.
Interventions
NameTypeDescription
Letermovir oral granulesDRUGGranules administered orally based on age, weight, and whether participant takes cyclosporin A as a concomitant medication.
Letermovir tabletDRUGTablet administered orally based on age, weight, and whether participant takes cyclosporin A as a concomitant medication.
Letermovir intravenousDRUGLetermovir administered intravenously based on age, weight, and whether participant takes cyclosporin A as a concomitant medication.
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Eligibility Criteria
Age RangeN/A — 17 Years
SexALL
Healthy VolunteersNo
Study Sites40

Inclusion Criteria: * All participants 12 to \<18 years old must have documented positive CMV serostatus (CMV IgG seropositive) for the recipient (R+) within 90 days prior to enrollment. Participants from birth to \<12 years old must have documented positive CMV serostatus (CMV IgG seropositive) fo...

Countries:United StatesAustraliaColombiaFranceGermanyIsraelJapanMexicoPolandSpainTurkey (Türkiye)
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