Vaccine Immune Recovery After Leukemia (VIRAL)

A Prospective Cohort Study to Define Infectious Burden, the Seroprevalence of Vaccine Preventable Pathogens and Immune Recovery in the First Year Following Completion of Therapy in Patients With Acute Lymphoblastic Leukemia (ALL)

This observational study aims to assess recovery of the immune system and immunity to vaccine-preventable diseases in children, adolescents, and young adults who recently completed treatment for acute lymphoblastic leukemia (ALL). Several children's hospitals in the United States are participating in the study, which will enroll up to 100 pediatric participants. The study is intended to determine the rate of infection after leukemia treatment and to inform future studies and recommendations about whether children and adolescents who have leukemia should receive additional vaccine doses or boosters after treatment.

Study Overview

• Status: Completed
• Conditions: Acute Lymphoblastic Leukemia, Pediatric
• Intervention / Treatment: Other: Observational only: Serology and flow cytometry for ALL cohort participants; Other: Observational only: Infection rates

• Study Type: Observational
• Enrollment (Actual): 89

Contacts and Locations

Study Locations

• United States
  • Illinois
    • Chicago, Illinois, United States, 60611
      • Ann & Robert H. Lurie Children's Hospital of Chicago
  • Michigan
    • Grand Rapids, Michigan, United States, 49503
      • Helen DeVos Children's Hospital
  • Pennsylvania
    • Philadelphia, Pennsylvania, United States, 19104
      • Children's Hospital of Philadelphia
  • Tennessee
    • Nashville, Tennessee, United States, 37232
      • Monroe Carell Jr. Children's Hospital at Vanderbilt
  • Texas
    • San Antonio, Texas, United States, 78207
      • CHRISTUS Children's (Affiliate of Baylor College of Medicine)
  • Washington
    • Seattle, Washington, United States, 98105
      • Seattle Children's Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 3 years to 21 years (Child, Adult)
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Children, adolescents, and young adults receiving care at a participating pediatric oncology/hematology center who recently completed or will soon complete treatment for acute lymphoblastic leukemia

Description

Inclusion Criteria:

• Children, adolescents, and young adults diagnosed with B or T ALL at age 12 months or older
• Completed ALL chemotherapy within the past three months or will complete ALL chemotherapy in the upcoming three months
• Three years of age or older at time of enrollment

Exclusion Criteria:

• Diagnosis of infant ALL
• Evidence of disease relapse
• History of primary immunodeficiency (except related to Down Syndrome)
• History of a stem cell transplant or cellular immunotherapy
• History of prior malignancy or condition requiring chemotherapy other than for current ALL diagnosis

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Intervention / Treatment

Children, adolescents, and young adults who recently completed ALL treatment; This cohort of participants who recently completed leukemia therapy will be assessed for infection incidence during the year following treatment and give blood samples to be measured for antibodies to vaccine-preventable diseases. A small subset will also have their blood samples tested for B and T cell recovery.

Other: Observational only: Serology and flow cytometry for ALL cohort participants; Blood samples from ALL cohort participants will be tested to measure antibodies to vaccine-preventable diseases and immune recovery; Other: Observational only: Infection rates; Number of infections during the study period will be obtained and infection incidence rates calculated during the first year off-chemotherapy.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incident Infection Rate in Participants During the First Year Post-acute Lymphoblastic Leukemia Therapy	Infections include clinical and/or microbiologically confirmed infections as well as patient-reported infections during follow-up. All unique infections for a given subject will be captured and included in the final infection rate per person time estimate. The total number of unique infections identified within the first year after completing chemotherapy will be reported as a rate per patient-year. Patients will be censored at time of loss to follow-up, relapse, or death.	1 year

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of Patients With Seroprevalence of Measles Antibodies at Each Study Timepoint	The seroprevalence proportions for measles antibodies will be determined for the entire cohort and by demographics at each study follow-up time point (3, 6, and 12 months). Additionally, seroprevalence at each time point will be described for participants who had and had not completed their primary vaccine series before starting chemotherapy.	1 year
Proportion of Patients With Seroprevalence of Varicella Antibodies at Each Study Timepoint	The seroprevalence proportions for varicella antibodies will be determined for the entire cohort and by demographics at each study follow-up time point (3, 6, and 12 months). Additionally, seroprevalence at each time point will be described for participants who had and had not completed their primary vaccine series before starting chemotherapy.	1 year
Proportion of Patients With Seroprevalence of Pneumococcus Antibodies at Each Study Timepoint	The seroprevalence proportions for pneumococcal antibodies (23 serotypes) will be determined for the entire cohort and by demographics at each study follow-up time point (3, 6, and 12 months). Additionally, seroprevalence at each time point will be described for participants who had and had not completed their primary vaccine series before starting chemotherapy.	1 year

Collaborators and Investigators

• Sponsor: Children's Hospital of Philadelphia
• Collaborators: Merck Sharp & Dohme LLC
• Investigators: Principal Investigator: Brian T Fisher, DO MSCE MPH, Children's Hospital of Philadelphia

Study record dates

Study Major Dates

• Study Start (Actual): September 28, 2022
• Primary Completion (Actual): October 31, 2025
• Study Completion (Actual): November 30, 2025

Study Registration Dates

• First Submitted: November 9, 2022
• First Submitted That Met QC Criteria: November 9, 2022
• First Posted (Actual): November 18, 2022

Study Record Updates

• Last Update Posted (Actual): January 26, 2026
• Last Update Submitted That Met QC Criteria: January 7, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: chemotherapy; pneumococcal vaccines; acute lymphoblastic leukemia; measles vaccine; antineoplastic agents; varicella vaccine; chickenpox vaccine
• Additional Relevant MeSH Terms: Neoplasms; Immune System Diseases; Neoplasms by Histologic Type; Hematologic Diseases; Lymphatic Diseases; Lymphoproliferative Disorders; Immunoproliferative Disorders; Leukemia, Lymphoid; Leukemia; Hemic and Lymphatic Diseases; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Investigative Techniques; Clinical Laboratory Techniques; Diagnostic Techniques and Procedures; Diagnosis; Cytological Techniques; Chemistry Techniques, Analytical; Cell Separation; Photometry; Fluorometry; Luminescent Measurements; Cytophotometry; Flow Cytometry
• Other Study ID Numbers: 21-019426; 61366 (Other Grant/Funding Number: Merck Sharp and Dohme LLC)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No