NCT05711667

A Study of the Drug Letermovir as Prevention of Cytomegalovirus Infection After Stem Cell Transplant in Pediatric Patients

Letermovir Prophylaxis for Cytomegalovirus in Pediatric Hematopoietic Cell Transplantation

• Status: Recruiting
• Phase: Phase 3
• Study type: Interventional
• Enrollment: 105 (estimated)
• Sponsor: Children's Oncology Group · Network
• Sex: All
• Age: 2 Years – 18 Years
• Healthy volunteers: Not accepted

Summary

This phase III single arm trial determines whether taking prophylactic letermovir will reduce the likelihood of infection with cytomegalovirus (CMV) in children and adolescents after stem cell transplant compared to estimated rate of infection without prophylaxis. The treatments used to prepare for HCT reduce the body's natural infection-fighting ability and increase the likelihood of an infection with a virus called cytomegalovirus. "Prophylaxis" means to take a drug to prevent a disease or side effect. Letermovir is an antiviral drug that stops cytomegalovirus from multiplying and may prevent cytomegalovirus infection and make the disease less severe.

Detailed description

PRIMARY OBJECTIVE: I. To evaluate the efficacy of letermovir prophylaxis in the prevention of clinically significant CMV infection through Week 14 (\~100 days) post-transplant in children and adolescents receiving allogeneic hematopoietic cell transplant (allo-HCT). SECONDARY OBJECTIVE: I. To evaluate the efficacy of letermovir prophylaxis as assessed by CMV-free survival through 24 weeks (\~6 months) post-transplant in pediatric patients. EXPLORATORY OBJECTIVES: I. To evaluate the incidence of clinically significant CMV infection through 24 and 52 weeks post-transplant in patients who receive letermovir prophylaxis. II. To evaluate overall survival post-transplant in patients who receive letermovir prophylaxis. III. To evaluate time to engraftment and describe the cumulative incidence of non-engraftment among patients who receive letermovir. IV. To examine the following clinically significant adverse events among patients exposed to letermovir: the total duration of neutropenia through week 14 (\~100 days) post-transplant, the cumulative incidence of acute kidney injury and chronic kidney disease by 52 weeks post-transplant, and total inpatient hospital days by 14 weeks (\~100 days) and 52 weeks post-transplant. V. Describe patterns of anti-viral resistance at the onset of CMV DNAemia after allo-HCT among patients who receive letermovir prophylaxis. VI. To describe immune reconstitution and CMV-specific immunity among patients who receive letermovir prophylaxis. OUTLINE: Enrolled patients will be added to the single arm of the study and receive letermovir prophylaxis. ARM A: Patients receive letermovir orally (PO) or intravenously (IV) over 60 minutes once daily (QD) starting on day +1 post-transplant for 14 weeks. Patients undergo collection of blood samples for CMV polymerase chain reaction (PCR) analysis weekly for 14 weeks, every 2 weeks until week 24, week 32, week 40 and week 52. ARM B (CLOSED TO ACCRUAL 09/29/2025): Patients undergo collection of blood samples for CMV PCR analysis weekly for 14 weeks, every 2 weeks until week 24, week 32, week 40 and week 52.

Conditions

• Hematopoietic and Lymphoid Cell Neoplasm
• Malignant Solid Neoplasm

Interventions

Type	Name	Description
PROCEDURE	Biospecimen Collection	Undergo collection of blood samples
DRUG	Letermovir	Given PO or IV

Timeline

• Start date: 2024-07-11
• Primary completion: 2029-06-30
• Completion: 2029-06-30
• First posted: 2023-02-03
• Last updated: 2026-02-24

Locations

28 sites across 1 country: United States

Regulatory

• FDA-regulated drug study